There are some genes that are only activated in the very first days of an embryos existence. Once they have accomplished their task, they are shut down forever, unlike most of our genes, which remain active throughout our ...
Scientists have now discovered a new way to turn off imprinted genes - by chemically tagging histones, proteins that organize DNA.
C75 The discovery of frequent inactivation of BLIMP1 in activated B cell-like DLBCLindicates that BLIMP1 has an important role in the pathogenesisof this lymphoma subtype, and possibly functions as a tumor suppressor gene. However a recent report shows that the presence of variable percentages of BLIMP1-positive tumor cells in about half of DLBCL cases, and patients with higher BLIMP1 expression are significantly correlated with shorter failure free survival. This raises the possibility that higher BLIMP1 expression could possibly promote the development of lymphoma. Deregulated BCL-6 expression contributes to lymphomagenesis in part by functional inactivation of p53. We found that BLIMP1 acts in an auto-regulatory feedback loop that controls p53 activity through repression of p53 transcription. Our finding that BLIMP1 represses p53 expression suggests that high expression of BLIMP1 might also promote the development of tumor by suppression of p53 activation. It would be of interest to study the ...
Sense Transgene-induced Silencing is Impaired in dcl2 Mutant Plants, but Enhanced in dcl4 Mutants.(A) The diagram shows the coding region of the silenced GUS se
Please note: Your browser does not support the features used on Addgenes website. You may not be able to create an account or request plasmids through this website until you upgrade your browser. Learn more ...
(Medical Xpress)-A study led by Yale Cancer Center may provide clues to how some aggressive cancers turn off, or silence, genes critical to suppressing tumors. The findings, published in the journal Cell Reports, suggest ...
Implementation of two-region transition matrix T. Silent state is replaced by the begin state in first row and by end state in last column. Each row is norma
Gentaur molecular products has all kinds of products like :search , EpigenTek \ EpiQuik DNA Methyltransferase DNMT Activity_Inhibition Assay Kit Fluorometric \ P-3004-48 for more molecular products just contact us
Grx2 siRNA (h), shRNA and Lentiviral Particle Gene Silencers are designed to knockdown gene expression of human Grx2. Cited in 1 publications
RNA interference (RNAi) is an important pathway that is used in many different organisms to regulate gene expression. This animation introduces the principles of RNAi involving small interfering RNAs (siRNAs) and microRNAs (miRNAs). We take you on an audio-visual journey through the steps of gene expression and show you an up-to-date view of how RNAi can silence specific mRNAs in the cytoplasm.. ...
One type involves attaching methyl groups to pieces of DNA called promoters, which reside immediately upstream of individual gene sequences (between genes), that tell the machinery that follows genetic instructions to "start reading here." The attachment of a methyl group to a promoter generally interferes with this and silences a nearby gene. However, ancient organisms such as plants and insects have less methylation between their genes, and more of it within the coding regions of the genes themselves (within gene bodies). Such gene-body methylation has been shown to encourage rather than silence gene expression ...
Cyclin-dependent kinase 9 (CDK9) promotes transcriptional elongation through RNAPII pause release. We now report that CDK9 is also essential for maintaining gene silencing at heterochromatic loci. Through a live cell drug screen with genetic confirmation, we discovered that CDK9 inhibition reactivat …
RNAi is a widely used methodology for gene silencing. The action mechanism of siRNA molecules has been well studied in recent years, and the technique..
Is there such a thing as a dog silencer to stop dog barking? Bark Off claims it has the best dog silencer on the market so read reviews before you buy online or in stores.
Methylation of CpG island promoters is an epigenetic event that can effectively silence transcription over multiple cell generations. was achieved specifically through Tet3-mediated hydroxymethylation. Collectively our findings reveal a new mechanism that may be exploited to facilitate therapeutic DNA demethylation to reverse kidney fibrosis. In recent years epigenetics have emerged as determinants of fibrosis in the kidney (and other tissues as well).1-5 Furthermore epigenetics have been implied to contribute to the individual susceptibilities of CKD patients to develop fibrosis.1-3 Among the known epigenetic mechanisms methylation of CpG island promoters (referred to as DNA methylation) is the most potent to silence transcription of affected genes.6 Because transcriptional silencing of affected genes has been shown to causally contribute to fibroblast activation and Sapitinib fibrogenesis inhibition or reversal of such aberrant methylation is considered beneficial for the kidney.3 Although in ...
CpG island hypermethylation is an epigenetic control aberration that is important for gene inactivation in cancer cells. Hypermethylation of CpG islands has been described in almost every type of tumor. Many important cellular pathways, such as DNA repair (hMLH1, for example), cell cycle (p14ARF), apoptosis (DAPK), cell adherence (CDH1, CDH13), are inactivated by this epigenetic lesion. Hypermethylation is linked to methyl-binding proteins, DNA methyltransferases and histone deacetylase, but the degree to which this process selectively silences tumor suppressor genes continues to remain a vibrant field of study. The list for hypermethylated genes is growing and functional and genetic studies are being performed to determine which hypermethylation events are relevant for tumorigenesis. Basic as well as translational research will be needed to understand the mechanisms and roles of CpG island hypermethylation in cancer. The first discovery of methylation in a CpG island of a tumor suppressor gene ...
Fu et al. demonstrate a requirement for the heterochromatin factors CMT and DDM1 in RNA-directed DNA methylation in maize. Plant Cell https://doi.org/10.1105/
Enterokinase siRNA (h), shRNA and Lentiviral Particle Gene Silencers are designed to knockdown gene expression of human Enterokinase
TY - JOUR. T1 - Epigenetic genes regulated by the BRAFV600E signaling are associated with alterations in the methylation and expression of tumor suppressor genes and patient survival in melanoma. AU - Liu, Dingxie. AU - Liu, Xuan. AU - Xing, Michael Mingzhao. PY - 2012/8/17. Y1 - 2012/8/17. N2 - We have previously reported that the BRAFV600E signaling causes genome-wide aberrations in gene methylation in melanoma cells. To explore the potential molecular mechanisms for this epigenetic effect of BRAFV600E, in this in silico study we analyzed 11 microarray datasets retrieved from NCBI GEO database and examined the relationship of the expression of the epigenetic genes (genes involved in epigenetic regulation) with BRAFV600E signaling, methylation and expression of tumor-suppressor genes (TSGs) in melanoma, and patient survival with this cancer. Among 273 epigenetic genes examined, 12 genes were down-regulated (named DD genes) and 16 were up-regulated (UU genes) by suppression of the BRAFV600E ...
The most enjoyable part in following RNAi Therapeutics is to look at the rich stream of scientific data and determine the absolute maturity and competitive position of the technologies and companies involved, as well as getting a glimpse at relationship dynamics. I therefore thought to share today two examples of this that I picked up recently. One is a paper by Sirna Therapeutics/Merck shedding some light on their approach towards RNAi pharmacology and RNAi trigger design. The other is some intriguing evidence that Silence Therapeutics most important gene target, PKN3, is gaining traction in the pharmaceutical space. Studying the pharmacology of siRNA delivery. Pei and colleagues from Merck published in RNA a nice paper on better understanding the pharmacology of siRNA delivery [Pei et al. (2010). Quantitative evaluation of siRNA delivery in vivo]. Unlike small molecules or even antibodies, the pharmacology of RNAi Therapeutics is more complex as simply measuring the raw tissue abundance of an ...
Author Summary Natural allelic variability is crucial for genetic improvement. While the genetic mechanisms leading to such variation have been studied in depth, relatively less is known about the role of epigenetic mechanisms in generation of allelic diversity. Paramutation is a phenomenon in which one allele can silence another allele in trans and, once established, such epigenetic silencing is heritable. To further understand the molecular components of paramutation, we characterized two epialleles of the pericarp color1 (p1) gene of maize, which originated from a common progenitor; however, only one of these alleles is paramutagenic. Results show that, while both alleles have high levels of symmetric (CG and CHG) methylation in a distal enhancer element, only the paramutagenic allele has higher levels of asymmetric (CHH) methylation. Since CHH methylation is imposed and maintained through RNA-mediated mechanisms, these results indicate that paramutation at the p1 locus involves RNA-mediated
Researchers at the Whitehead Institute and Memorial Sloan-Kettering Cancer Center have defined and analyzed the crystal structure of a yeast Argonaute protein bound to RNA. This complex plays a key role in the RNA interference (RNAi) pathway that silences gene expression. Describing the molecular structure of a eukaryotic Argonaute protein has been a goal of the RNAi field for close to a decade. "You can learn a lot from biochemical experiments, but to more fully understand a protein like Argonaute, its useful to know where all of the atoms are and which amino acids are playing important roles," says Whitehead Institute Member Dr. David Bartel, who is also an MIT professor of biology and a Howard Hughes Medical Institute (HHMI) investigator. "Learning the Argonaute crystal structure is an important step in understanding the RNAi biochemical pathway and will be the basis for many future experiments." The yeast Argonaute structure is described in the June 21, 2012 issue of Nature. In humans and ...
In recent years, the recognition of non-protein coding RNAs as a functional effector of genetic expression has been highlighted by the discovery of RNA interference (RNAi). RNAi is an intracellular phenomenon that enables the eukaryotic cell to utilize double-stranded RNA molecules to silence gene expression in a sequence-specific manner. The short interfering RNA (siRNA) pathway has been intensively investigated and continues to serve as the basis for the development of potent molecular genetic tools. The power of this technology is most clearly evidenced by the fact that siRNA effector molecules can be chemically synthesized and exogenously delivered to specifically target and silence any gene of choice. This capability enables not only basic research, but also opens the door to a new therapeutic modality. Furthermore, the introduction of certain chemical modifications to siRNA effectors can produce a more robust knockdown of gene expression, hence, optimizing serum stability and increasing target
Dr. Josephine Lai (Professor of Pharmacology, University of Arizona) is a pioneer in developing experimental designs and methods for delivering siRNA to the CNS for gene expression analysis.She and her team have documented these in the publication ...
The researchers determined that the protective effects of exosomes are mediated by microRNA, molecules that interfere with or silence gene expression. Further research is needed to understand more about the specific contents of the exosomes, said Stanislav Tomarev, Ph.D., a principal investigator at NEI and the studys coauthor.. "We need to know which particular microRNA - there are more than 2000 different microRNA molecules - are delivered into the retinal ganglion cells and what proteins or signaling pathways are being targeted upon arrival," said Tomarev. "We also need to attempt to target exosomes to specific sets of neurons and other cell types or groups of cells.". Finally, the most optimal exosome approach needs to be identified, Tomarev added. It may be that the best approach would be to combine exosomes with additional therapies. From a treatment feasibility standpoint, a lot will depend on how frequently exosomes need to be administered to achieve a therapeutic effect.. ...
With age, expression of microRNA-141-3p (small molecule) that can silence others goes way up while stromal-cell derived factor, or SDF-1 (key signaling molecule) helps ...
Anew detection mechanism for the control of successful siRNA delivery to cells or tissue is introduced using a siRNA-based probe that is capable of inducing a ...
Fig. 3. Chromocentres are located close to the nuclear periphery. (A) NucleusJ was used to compute the distance between the limit of the Hoechst DNA staining (blue) and the chromocentres (Cc, pink), boundary [d(Cc border)] or barycentre [d(Cc barycentre)]. The barycentre of the nucleus d(Nuc barycentre) (white cross) is also indicated. (B) Graphical representation of chromocentre distribution in respect to the limit of Hoechst DNA staining among the three cell types. The theoretical uniform distribution of chromocentres (top) is compared to observed distributions for d(Cc border) (middle) and d(Cc barycentre) (bottom). The uniform distribution of chromocentres is obtained by placing the same number of chromocentres as in the corresponding datasets between the periphery and the corresponding nuclear barycentres, for each nucleus of the dataset. Chromocenters and nuclei numbers are given at the bottom of the figure. The scales of the graphs were standardized by setting the maximum d(Nuc ...
Sigma-Aldrich offers abstracts and full-text articles by [Zhang, DD; Wang, WT; Xiong, J; Xie, XM; Cui, SS; Zhao, ZG; Li, MJ; Zhang, ZQ; Hao et al.].
IMO I think that people go with siRNA first to see if their siRNA sequence works and you get good knockdown. If you get good knowndown, then you can make the shRNA plasmid. But if you dont see good knockdown you end up making a new siRNA. If you went to shRNA first and then found that there is no knowndown, then it is a waste of time and money.. ...
chemical synthesized siRNA and rapidly dividing cells - posted in siRNA, microRNA and RNAi: Hi all, I am new to RNAi area. Your suggestion and opinion are very important to me If i am to use some rapidly dividing cells (e.g. HEK 293 cells) to perform RNAi study, is it not wise to use chemically synthesized siRNA? I have this wonder because in this case the RNAi effects may be too insignificant to be detectable. Is my concept correct? since i think for chemically synthesized siRNA, i...
Short interfering RNAs (siRNAs) are a popular method for gene-knockdown, acting by degrading the target mRNA. Before performing experiments it is invaluable to locate and evaluate previous knockdown experiments for the gene of interest.
Maintaining and acquiring the pluripotent cell state in plants is critical to tissue regeneration and vegetative multiplication. Histone-based epigenetic mechanisms are important for regulating this undifferentiated state. Here we report the use of genetic and pharmacological experimental approaches to show that Arabidopsis cell suspensions and calluses specifically repress some genes as a result of promoter DNA hypermethylation. We found that promoters of the MAPK12, GSTU10 and BXL1 genes become hypermethylated in callus cells and that hypermethylation also affects the TTG1, GSTF5, SUVH8, fimbrin and CCD7 genes in cell suspensions. Promoter hypermethylation in undifferentiated cells was associated with histone hypoacetylation and primarily occurred at CpG sites. Accordingly, we found that the process specifically depends on MET1 and DRM2 methyltransferases, as demonstrated with DNA methyltransferase mutants. Our results suggest that promoter DNA methylation may be another important epigenetic ...
TY - CHAP. T1 - Short hairpin RNA-mediated gene silencing. AU - Lambeth, Luke S. AU - Smith, Craig A.. PY - 2013. Y1 - 2013. N2 - Since thefirst application of RNA interference (RNAi) in mammalian cells, the expression of short hairpin RNAs (shRNAs) for targeted gene silencing has become a benchmark technology. Using plasmid and viral vectoring systems, the transcription of shRNA precursors that are effectively processed by the RNAi pathway can lead to potent gene knockdown. The past decade has seen continual advancement and improvement to the various strategies that can be used for shRNA delivery, and the use of shRNAs for clinical applications is well underway. Driving these developments has been the many benefits afforded by shRNA technologies, including the stable integration of expression constructs for long-term expression, infection of difficultto-target cell lines and tissues using viral vectors, and the temporal control of shRNA transcription by inducible promoters. The use of different ...
TY - JOUR. T1 - Methylation-associated silencing of the heat shock protein 47 gene in human neuroblastoma. AU - Yang, Qiwei. AU - Liu, Shuqing. AU - Tian, Yufeng. AU - Hasan, Chiler. AU - Kersey, Donna. AU - Salwen, Helen R.. AU - Chlenski, Alexandre. AU - Perlman, Elizabeth J.. AU - Cohn, Susan L.. PY - 2004/7/1. Y1 - 2004/7/1. N2 - Hypermethylation of gene promoter CpG islands is a frequent mechanism for gene inactivation in a variety of human cancers, including neuroblastoma (NB). We demonstrated recently that treatment with the demethylating agent 5′-aza-2′-deoxycytidine (5-Aza-dC) significantly inhibited NB growth in vivo. In an effort to identify the genes and biological pathways that are responsible for the impaired NB tumor growth observed after treatment with 5-Aza-dC, we performed genome-wide gene expression analysis of control and treated NBL-W-S NB cells. We found ≥2-3-fold changes in expression of 44 genes that play roles in angiogenesis, apoptosis, cell adhesion, ...
The present invention is directed to methods and materials for RNA-mediated gene assembly from oligonucleotide sequences. In some embodiments, the oligonucleotides used for gene assembly are provided in an array format. An RNA polymerase promoter is appended to surface-bound oligonucleotides and a plurality of RNA copies of each oligonucleotide are then produced with an RNA polymerase. These RNA molecules self-assemble into a desired full-length RNA transcript by hybridization and ligation. The resulting RNA transcript may then be converted into double strand DNA useful in a variety of applications including protein expression.
During meiosis in the filamentous fungus Neurospora crassa, unpaired genes are identified and silenced by a process known as meiotic silencing by unpaired DNA (MSUD). Previous work has uncovered six proteins required for MSUD, all of which are also essential for meiotic progression. Additionally, they all localize in the perinuclear region, suggesting that it is a center of MSUD activity. Nevertheless, at least a subset of MSUD proteins must be present inside the nucleus, as unpaired DNA recognition undoubtedly takes place there. In this study, we identified and characterized two new proteins required for MSUD, namely SAD-4 and SAD-5. Both are previously uncharacterized proteins specific to Ascomycetes, with SAD-4 having a range that spans several fungal classes and SAD-5 seemingly restricted to a single order. Both genes appear to be predominantly expressed in the sexual phase, as molecular study combined with analysis of publically available mRNA-seq datasets failed to detect significant ...
DNA methylation is an important epigenetic modification that serves to protect the genome from propagating mutations, and to regulate gene expression. Aberrant...
Several years ago, I posted a blog about long noncoding RNAs (lncRNAs), which are defined as non-protein coding transcripts in the range of ~200 nt to ~100 kb long. Interest in lncRNA is driven in large part by a collective scientific desire to uncover and understand the existence and function of all forms of "RNA dark matter," so named by analogy to "dark energy" in cosmology. The lncRNA component of RNA dark matter is certainly generated from transcription of noncoding (formerly "junk") DNA, but much has yet to be elucidated about function.. Following are tag lines from my Jan 23, 2018 blog titled Long Noncoding RNA (lncRNA) Revisted, which provides some updates on lncRNA dark matter.. ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Meiotic silencing by unpaired DNA is an RNAi-mediated pathway that functions to silence unpaired genes during the sexual phase of Neurospora crassa. The presence of a gene insertion or deletion causes an unpairing event during the homolog pairing stage. My dissertations aim was to further characterize this new RNAi pathway. First, I was involved in adapting the in vivo protein interaction technique Bimolecular Fluorescence Complementation (BiFC) to N. crassa to investigate SAD-1/SAD-2 interaction. SAD-1 and SAD-2 interact in the perinuclear region, suggesting that SAD-2 functions to bring SAD-1 to its proper location. Next, I was involved in identifying components of quelling that also function in meiotic silencing. dcl-1 and qip were found to be important for sexual development and meiotic silencing. DCL-1 and QIP also localize in the perinuclear region, implicating these genes in meiotic silencing. Finally, I tested the mating type locus for immunity to meiotic silencing. Unpaired reporter ...
Circulating Long Noncoding RNA as a Potential Target for Prostate Cancer. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
In the present study, we showed that a mild cooling of the cortex reversibly eliminated silent states and led to persistent thalamocortical activity in lightly anesthetized mice. Spontaneous IPSPs within the VPM neurons disappeared during cooling-induced cortical activation. Similarly, mild cortical cooling prevented the generation of cortical silent states in non-anesthetized head-restrained mice. Under the lesser physiological condition of deep anesthesia, a moderate cooling of the cortex reduced slow-wave synchrony but did not prevent the generation of slow waves. It also evoked fast cortical LFP spikes with frequencies ranging from 6 to 9 Hz, which correlated to spindle-like IPSPs within the VPM neurons and depolarizing events within the PO neurons. Our data point to a strong cortical control of thalamic activities.. The essential finding of this study is that a moderate cortical cooling in lightly anesthetized or naturally sleeping mice transforms the slow-wave pattern of neuronal activity ...
Cancer has long been viewed as a genetic disease; however, epigenetic silencing as the result of aberrant promoter DNA methylation is frequently associated with cancer development, suggesting an epigenetic component to the disease. Nonetheless, it has remained unclear whether an epimutation (an aberrant change in epigenetic regulation) can induce tumorigenesis. Here, we exploited a functionally validated ...
In mammalian cells the introduction of small 21-23 nucleotide sequence-specific RNA duplexes (small/short interfering RNAs, siRNAs) can act to initiate post-transcriptional gene knockdown and avoid triggering non-specific effects in mammalian cells
Benenson and colleagues engineered a target gene to be sensitive to several different siRNAs of their own design. In the simplest case, they introduced a single siRNA molecule to switch off a target gene that encoded a fluorescent protein. In more complex cases, a pair of siRNAs or either of two siRNAs switched off another target gene, which in turn switched off a gene for a fluorescent protein. To make sure the system worked as intended, the researchers based their siRNAs on those of other species, they report in a paper published online today by Nature Biotechnology ...
The first in a new class of gene-silencing drugs, known as inclisiran, has been shown to halve cholesterol levels in patients at risk of cardiovascular disease.
Accell siRNA has a higher working concentration than siGENOME or ON-TARGETplus siRNA products. Use this tool as a guideline for ordering the appropriate amount of Accell siRNA for your cell culture format. http: //dharmacon. horizondiscovery. com/resources/tools-and-calculators/sirna-calculators ...
RASSF3山羊多克隆抗体(ab82168)可与人样本反应并经WB, ELISA实验严格验证。中国75%以上现货,所有产品均提供质保服务,可通过电话、电邮或微信获得本地专属技术支持。
目前从事棉花与害虫互作分子机制研究,主要通过多重组学(转录组、蛋白质组,代谢组等)手段,挖掘棉花自身的抗虫防御相关基因,利用高效的植物基因编辑技术体系验证相关基因的功能。同时分离鉴定多种外源的植物抗虫基因、抗性机制(新型BT基因、凝集素基因,RNAi等),通过细胞核转化和叶绿体转化表达体系,提高植物的抗虫性。. ...
TY - JOUR. T1 - Role for piRNAs and noncoding RNA in de novo DNA methylation of the imprinted mouse Rasgrf1 locus. AU - Watanabe, Toshiaki. AU - Tomizawa, Shin Ichi. AU - Mitsuya, Kohzoh. AU - Totoki, Yasushi. AU - Yamamoto, Yasuhiro. AU - Kuramochi-Miyagawa, Satomi. AU - Iida, Naoko. AU - Hoki, Yuko. AU - Murphy, Patrick J.. AU - Toyoda, Atsushi. AU - Gotoh, Kengo. AU - Hiura, Hitoshi. AU - Arima, Takahiro. AU - Fujiyama, Asao. AU - Sado, Takashi. AU - Shibata, Tatsuhiro. AU - Nakano, Toru. AU - Lin, Haifan. AU - Ichiyanagi, Kenji. AU - Soloway, Paul D.. AU - Sasaki, Hiroyuki. PY - 2011/5/13. Y1 - 2011/5/13. N2 - Genomic imprinting causes parental origin - specific monoallelic gene expression through differential DNA methylation established in the parental germ line. However, the mechanisms underlying how specific sequences are selectively methylated are not fully understood. We have found that the components of the PIWI-interacting RNA (piRNA) pathway are required for de novo methylation of ...
5219 Insulin growth factor binding protein-3 (IGFBP-3) has been postulated to be a mediator of growth suppression signal. In our previous study, IGFBP-3 was found as an invasion suppressor gene in ovarian endometrioid carcinoma (EC) (Oncogene 2007, on line). Since promoter methylation can silence gene expression, we investigated whether hypermethylation of the IGFBP-3 promoter is involved in the loss of IGFBP-3 expression in ovarian EC. By methylation-specific PCR assay, IGFBP-3 promoter was found methylated in the higher invasive ovarian cancer cell line OVTW59-P4, compared with the lower invasive P0 cell line. After treatment with DNA methyltransferase inhibitor 5-aza-2-deoxycytidine, P4 showed restoration of IGFBP-3 expression. Methylation status correlated with IGFBP-3 mRNA and protein levels. By bisulfite genomic DNA sequencing, the hyprermethylated CpG sites were found focused at the -210, -206, -183 and -179 sites of p53 consensus binding sequence in IGFBP-3 promoter region. A luciferase ...
RNA silencing pathways control the expression of genes and other DNA loci by the action of small RNA molecules and are found in many eukaryotes. In plants there are a number of RNA silencing pathways, of which RNA-directed DNA methylation (RdDM) is one. In this pathway the small RNA molecules direct DNA methylation, resulting in the down regulation of expression of the target locus. In terms of the mechanism of the pathway it is mostly well characterised but several gaps exist in our knowledge. These relate to its initiation, where it is not known how RdDM targets the correct locus; methylation, where it is unclear how the action of small RNAs triggers methylation; and chromatin modification, where it is unclear how methylated DNA is converted into higher order chromatin modification. These gaps in the pathway raised the possibility of the involvement of novel proteins and so this project aimed to identify and characterise mutants in these proteins. Screening of a library of putative RdDM ...
Background: Detection of circulating DNA can be applied for the diagnosis of many malignant neoplasms, including the hepatocellular carcinoma (HCC). The molecular pathogenesis of HCC is complex, involving different genetic and epigenetic alterations, chromosomal aberrations, gene mutations and altered molecular pathways. RASSF1A is a well-established tumor suppressor gene which suffers frequent inactivation due to promoter hypermethylation of CPG islands in multiple tumors including HCC, resulting in the reduction or loss of gene expression. Objective: To examine the role of circulating RASSF1A as a non-invasive diagnostic marker for HCC. Participant and Methods: A total of 45 HCC patients with a background of HCV infection, 40 cases of HCV infection without tumours and 40 apparently healthy controls were subjected to full history taking, clinical examination, routine laboratory investigations, assessment of serum AFP and detection of circulating hypermethylated RASSF1A gene by methylation-sensitive
This method is based on the identification of aberrant hypermethylation at an internal promoter region of DNMT3A, which occurs in about 40% of AML patients. High DNAm levels at this site are particularly observed in samples from AML patients without genetic mutations in DNMT3A. Epimutations and mutations of DNMT3A are associated with related gene expression changes such as upregulation of the homeobox genes in HOXA and HOXB clusters. Furthermore, epimutations in DNMT3A are enriched in patients with poor or intermediate cytogenetic risk, and in patients with shorter event-free survival and overall survival. Taken together, aberrant DNA hypermethylation within the DNMT3A gene, in analogy to DNMT3A mutations, is frequently observed in AML and both modifications seem to be useful for risk stratification or choice of therapeutic regimen. Commercial Opportunities The screening for aberrant DNA hypermethylation within DNMT3A provides a relatively simple and cost-effective diagnostic approach for AML. ...
Advances in basic research have shed light on key alterations that contribute to the development of renal neoplasia. Detailed studies of pathology have underscored the morphologic heterogeneity of renal cancers (30) . Genetic and epigenetic studies using a variety of technologies have shown that renal cancers are characterized by specific genetic and epigenetic alterations (e.g., loss of heterozygosity at the VHL locus; Ref. 31 ) and hypermethylation of RASSF1A, TIMP3, p16, GSTP1, and CDH1 (8, 9, 10 ,, 12 , 13 , 32) . However, these advances in basic research have not yet translated into the development of reliable diagnostic markers for renal cancer.. In a previous study using the same set of samples, we demonstrated that microsatellite analysis of urine DNA could detect the presence of malignancy in patients with clinically organ-confined renal cancer (19) . In the present study, 94% of primary kidney tumors harbored CpG island hypermethylation of at least two of nine cancer-related genes. ...
Multi-drug resistance is the biggest threat to long-term survival of cancer patients. Despite treatment, some tumor cells survive chemotherapy and become resistant to the drugs, causing follow-up treatments to fail. These drug-resistant tumors become untreatable and continue to flourish, ultimately killing the patient. Multi-drug resistance proteins expressed by tumor cells are a major source of resistance to conventional chemotherapeutic drugs. Small interfering RNAs (siRNAs) can silence these messenger RNAs that make multi-drug resistance proteins and EnGeneIC has discovered that EDVs can effectively load up to 10,000 copies of siRNA and deliver them directly to cancer cells. This process silences the respective messenger RNAs and makes the tumor cells sensitive to chemotherapeutic drugs which are subsequently delivered via the EDVs to eradicate the formerly drug resistant tumor. EnGeneIC has demonstrated in mouse studies carrying human drug resistant tumors and the data has been published in ...
|p|Promoter CpG methylation is a fundamental regulatory process of gene expression. TET proteins are active CpG demethylases converting 5-methylcyt...
RNA interference (RNAi) is a gene-silencing mechanism by which a ribonucleoprotein complex, the RNA-induced silencing complex (RISC) and a double-stranded (ds) short-interfering RNA (siRNA), targets a complementary mRNA for site-specific cleavage and subsequent degradation. While longer dsRNA are endogenously processed into 21- to 24-nucleotide (nt) siRNAs or miRNAs to induce gene silencing, RNAi studies in human cells typically use synthetic 19- to 20-nt siRNA duplexes with 2-nt overhangs at the 3-end of both strands. Here, we report that systematic synthesis and analysis of siRNAs with deletions at the passenger and/or guide strand revealed a short RNAi trigger, 16-nt siRNA, which induces potent RNAi in human cells. Our results indicate that the minimal requirement for dsRNA to trigger RNAi is an approximately 42 A A-form helix with approximately 1.5 helical turns. The 16-nt siRNA more effectively knocked down mRNA and protein levels than 19-nt siRNA when targeting the endogenous CDK9 gene,
Read "Loss of 5hmC identifies a new type of aberrant DNA hypermethylation in glioma, Human Molecular Genetics" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Notably, hypermethylation of the CDKN2A promoter region has been shown to lead to loss of p16 expression in 19% of primary and 33% metastatic melanomas.[59] DNA methyltransferase(DNMT) inhibitors namely 5-azacytidine, 5-aza-20-deoxycytidine(decitabine), fazarabine, and dihydro-5-azacytidine have been extensively studied ...
Development of an organism requires information contained minimally within a single cell. This information is inherited in two forms- the genome sequence and regulatory molecules. Little is understood about the types of the regulatory molecules inherited or the impact of parental experiences on them. However, environmental stimuli can alter gene expression without changing DNA sequence and these changes can be inherited suggesting heritable regulatory molecules are influenced by parental experience. Such changes could require communication of regulatory information between cells within an animal (systemic regulation) and across generations via germ cells (transgenerational regulation). Double- stranded RNA (dsRNA) introduced to an animal can silence a gene of matching sequence within that animal and this silencing can persist in progeny suggesting that RNA has the potential to transfer gene-specific regulatory information. Using RNA silencing in C. elegans, we identify conditions that facilitate ...
Gene silencing is the regulation of gene expression in a cell to prevent the expression of a certain gene. Gene silencing can occur during either transcription or translation and is often used in research. In particular, methods used to silence genes are being increasingly used to produce therapeutics to combat cancer and diseases, such as infectious diseases and neurodegenerative disorders. Gene silencing is often considered the same as gene knockdown. When genes are silenced, their expression is reduced. In contrast, when genes are knocked out, they are completely erased from the organisms genome and, thus, have no expression. Gene silencing is considered a gene knockdown mechanism since the methods used to silence genes, such as RNAi, CRISPR, or siRNA, generally reduce the expression of a gene by at least 70% but do not completely eliminate it. Methods using gene silencing are often considered better than gene knockouts since they allow researchers to study essential genes that are required ...
TY - CHAP. T1 - SiRNA therapeutic design. T2 - Tools and challenges. AU - Malefyt,Amanda P.. AU - Angart,Phillip A.. AU - Chan,Christina. AU - Walton,S. Patrick. PY - 2013/8/1. Y1 - 2013/8/1. N2 - Current RNA-based therapeutics are principally focused toward activating the RNA interference (RNAi) pathway through exogenous administration of short interfering RNAs (siRNAs) and sometimes short hairpin RNAs (shRNAs). The promise of RNAi-based therapeutics arises from their broad applicability and excellent specificity. This chapter reviews siRNA design strategies for improving intracellular interactions with the RNAi pathway proteins as well as key characteristics required for the design of optimal delivery vehicles to maximize specific silencing in only the cells of interest. The status of previous and ongoing clinical trials will be described as these provide insight for overcoming future challenges for long-term use of RNAi as a therapeutic modality.. AB - Current RNA-based therapeutics are ...
You can add the following controls to your FlexiPlate siRNA plate: AllStars Negative Control siRNA, AllStars Cell Death Control siRNA, Negative Control siRNA, Human GAPDH siRNA, Human Beta-Actin siRNA, Human and mouse MAPK1 siRNA, Human or mouse Lamin A/C siRNA, Mouse AKT1 siRNA, or other siRNAs from GeneGlobe, such as HP Validated siRNAs. ...
Epigenetic phenomena, as The Alchemist mentioned, are not related directly to the genome. Outside influences and DNA methylation can cause epigenetic ef...
Gene silencing is a naturally occurring process by which genes can become shut off within a plant. When transgenes are introduced into plants they can also show gene silencing. Genes which share sequence similarity are said to be homologous. When transgenes showing homology to normal cellular genes are introduced they can show a special form of silencing called homology-dependent gene silencing and this typically results in the silencing of one or both genes ...
A fusion reagent for rapid and efficient gene silencing in living cells-the improvement of siRNA transfection Exceptionally efficient siRNA transfection, esp...
购买RASSF1a小鼠单克隆抗体[3F3](ab23950),RASSF1a抗体经WB,Flow Cyt验证,可与人,小鼠样本反应。12篇文献引用,产品出库一年都在质保范围内。中国现货速达。
TY - JOUR. T1 - Relationship of the aberrant DNA hypermethylation of cancer-related genes with carcinogenesis of endometrial cancer. AU - Banno, Kouji. AU - Yanokura, Megumi. AU - Susumu, Nobuyuki. AU - Kawaguchi, Makiko. AU - Hirao, Nobumaru. AU - Hirasawa, Akira. AU - Tsukazaki, Katsumi. AU - Aoki, Daisuke. PY - 2006/12/1. Y1 - 2006/12/1. N2 - Epigenetic abnormalities including the aberrant DNA hypermethylation of the promoter CpG islands play a key role in the mechanism of gene inactivation in cell carcinogenesis. To identify the genes associated with aberrant DNA hypermethylation in endometrial carcinogenesis, we studied the hypermethylation of the promoter regions of five genes: hMLH1, APC, E-cadherin, RAR-β and p16. The frequencies of aberrant hypermethylation were 40.4% (21/52) in hMLH1, 22% (11/50) in APC, 14% (7/50) in E- cadherin, and 2.3% (1/44) in RAR-β in endometrial cancer specimens. No aberrant DNA methylation was found in p16. In atypical endometrial hyperplasia, the ...
RNA-directed DNA methylation (RdDM) is a plant-specific de novo DNA methylation mechanism that requires long noncoding RNA (lncRNA) as scaffold to define target genomic loci. While the role of RdDM in maintaining genome stability is well established, how it regulates protein-coding genes remains poorly understood and few RdDM target genes have been identified. In this study, we obtained sequences of RdDM-associated lncRNAs using nuclear RNA immunoprecipitation against ARGONAUTE 4 (AGO4), a key component of RdDM that binds specifically with the lncRNA. Comparison of these lncRNAs with gene expression data of RdDM mutants identified novel RdDM target genes. Surprisingly, a large proportion of these target genes were repressed in RdDM mutants suggesting that they are normally activated by RdDM. These RdDM-activated genes are more enriched for gene body lncRNA than the RdDM-repressed genes. Histone modification and RNA analyses of several RdDM-activated stress response genes detected increased levels of
Our current view of DNA methylation processes is strongly moving: First, even if it was generally admitted that DNMT3A and DNMT3B are associated with de novo methylation and DNMT1 is associated with inheritance DNA methylation, these distinctions are now not so clear. Secondly, since one decade, many partners of DNMTs have been involved in both the regulation of DNA methylation activity and DNMT recruitment on DNA. The high diversity of interactions and the combination of these interactions let us to subclass the different DNMT-including complexes. For example, the DNMT3L/DNMT3A complex is mainly related to de novo DNA methylation in embryonic states, whereas the DNMT1/PCNA/UHRF1 complex is required for maintaining global DNA methylation following DNA replication. On the opposite to these unspecific DNA methylation machineries (no preferential DNA sequence), some recently identified DNMT-including complexes are recruited on specific DNA sequences. The coexistence of both types of DNA methylation (un
The long noncoding RNA, TINCR, functions as a competing endogenous RNA to regulate PDK1 expression by sponging miR-375 in gastric cancer Zhaoliang Chen,1 Hong Liu,1 Huili Yang,1 Yukai Gao,1 Gongwen Zhang,1 Jiaojiao Hu2 1Department of Oncology, Binzhou Central Hospital, Binzhou, Shandong, 2Department of Hematology, Zhongda Hospital, Southeast University, Nanjing, China Background: Accumulating evidence indicates that the long noncoding RNA, TINCR, plays a critical role in cancer progression and metastasis. However, the overall biological role and mechanisms of TINCR that were involved in human gastric cancer (GC) progression remain largely unknown.Methods: TINCR expression was measured in 56 paired tumor and adjacent nontumor tissue samples by real-time polymerase chain reaction (PCR). Insights of the mechanism of competitive endogenous RNAs (ceRNAs) were gained from bioinformatic analysis, luciferase assays. The effects of TINCR and miR-375 on GC cell apoptosis and proliferation were studied by RNA
Perez-Toledo, K., Rojas-Meza, A.P., Mancio-Silva, L., Hernandez-Cuevas, N.A., Delgadillo, D.M., Vargas, M., et al. (2009) Plasmodium falciparum heterochromatin protein 1 binds to tri-methylated histone 3 lysine 9 and is linked to mutually exclusive expression of var genes. Nucleic Acids Res 37: 2596-2606 ...
Cytogenetically normal acute myeloid leukemia (CN-AML) represents nearly 50% of human AML. Co-occurring mutations in the de novo DNA methyltransferase DNMT3A and the FMS related tyrosine kinase 3 FLT3 are common in CN-AML and confer a poorer prognosis. We demonstrate that mice with Flt3-internal-tandem duplication (Flt3ITD) and inducible deletion of Dnmt3a spontaneously develop a rapidly-lethal, completely-penetrant, and transplantable AML of normal karyotype. AML cells retain a single Dnmt3a floxed allele, revealing the oncogenic potential of Dnmt3a haploinsufficiency. FLT3-ITD/DNMT3A-mutant primary human and murine AML exhibit a similar pattern of global DNA methylation associated with changes in the expression of nearby genes. In the murine model, rescuing DNMT3A expression was accompanied by DNA re-methylation and loss of clonogenic potential, suggesting that Dnmt3a-mutant oncogenic effects are reversible. Dissection of the cellular architecture of the AML model using single-cell assays ...
This is a protocol to produce stable silencing efficacy and efficiency for VIGS using CymMV as a silencing vector for floral functional genomics in Phalaenopsis orchids. This protocol is established based on a method created by Lu et al. (2007), and then modified by Hsieh et al. (2013a; 2013b), Lu et al. (2012) successfully engineered a cloning vector (pCymMV-Gateway) in that the target gene fragment is simple to insert and can be manipulated with high efficiency. The silencing vector is inoculated into plants by Agro-inoculation by using Agrobacterium tumefaciens (A. tumefaciens) strain EHA105. Agro-infiltration of leaves for use in VIGS study of orchid flowers is a time saver and produces less damage to flower buds.
AMPK is a critical energy sensor and target for widely used antidiabetic drugs. In β-cells, elevated glucose concentrations lower AMPK activity, and the ablation of both catalytic subunits (βAMPKdKO mice) impairs insulin secretion in vivo and β-cell identity. MicroRNAs (miRNAs) are small RNAs that silence gene expression that are essential for pancreatic β-cell function and identity and altered in diabetes. Here, we have explored the miRNAs acting downstream of AMPK in mouse and human β-cells. We identified 14 down-regulated and 9 up-regulated miRNAs in βAMPKdKO vs. control islets. Gene ontology analysis of targeted transcripts revealed enrichment in pathways important for β-cell function and identity. The most down-regulated miRNA was miR-184 (miR-184-3p), an important regulator of β-cell function and compensatory expansion that is controlled by glucose and reduced in diabetes. We demonstrate that AMPK is a potent regulator and an important mediator of the negative effects of glucose on miR-184
RNAi refers to dsRNA-induced gene silencing, a cellular process that degrades RNA homologous to one strand of the dsRNA [1, 2]. The intermediates of long dsRNA-initiated RNAi are double-stranded small interfering RNAs (siRNA), typically 21-23 nucleotide (nt) long. The siRNAs, when introduced into cells, can be used to silence genes in mammalian systems where long dsRNAs prompt protein kinase R (PKR), RNase L, and interferon activities that result in non-specific RNA degradation and general shutdown of protein synthesis [3]. siRNAs can either be chemically synthesized then directly transfected into cells or can be generated inside the cell by introducing vectors that express short-hairpin RNA (shRNA) precursors of siRNAs. The process of shRNA into functional siRNA involves cellular RNAi machinery that naturally process genome encoded microRNAs (miRNA) that are responsible for cellular regulation of gene expression by modulating mRNA stability, translation, and chromatin structures ...
The first set of enzymes - methylases, in particular LIN-65 - add methyl groups to the DNA, which can silence promoters and thus suppress gene expression. By also opening up the mitochondrial genes, these methylases set the stage for the second set of enzymes - demethylases, in this case jmjd-1.2 and jmjd-3.1 - to ramp up transcription of the mitochondrial genes. When the researchers artificially increased production of the demethylases in worms, all lived longer, a result identical to what is observed after mitochondrial stress.. "By changing the epigenetic state, these enzymes are able to switch genes on and off," Dillin said.. This happens only in the brain of the worm, however, in areas that sense hunger or satiety.. "These genes are expressed in neurons that are sensing the nutritional status of the animal, and these signals emanate out to the periphery to change peripheral metabolism," he said.. When they profiled enzymes in short- and long-lived mice, they found up-regulation of these ...
siSTABLE GAPD Control siRNA is a validated positive control, guaranteed to silence GAPD in mouse cells. This control siRNA is chemically modified to significantly extend siRNA stability and is recommended for use as a positive control in experiments using siSTABLE modified siRNA against a target gene or where increased stability of the control is desired.. Also known as glyceraldehyde-3-phosphate dehydrogenase or GAPDH, GAPD is an important enzyme in carbohydrate metabolism that is well conserved across the animal kingdom. This gene is abundantly expressed in most cells, and because it is non-essential, knockdown of the corresponding mRNA does not affect cell viability. Targets accession number NM_001001303.. ...
Detail záznamu - Paramutation of tobacco transgenes by small RNA-mediated transcriptional gene silencing - Detail záznamu - Knihovna Akademie věd České republiky
SiRNAs exert their biological effect by guiding the degradation of their cognate mRNA sequence, thereby shutting down the corresponding protein production (gene silencing by RNA interference or RNAi). Due to this property, siRNAs are emerging as promising therapeutic agents for the treatment of inherited and acquired diseases, as well as research tools for the elucidation of gene function in both health and disease. Because of their lethality and prevalence, lung diseases have attracted particular attention as targets of siRNA-mediated cures. In addition, lung is accessible to therapeutic agents via multiple routes, e.g., through the nose and the mouth, thus obviating the need for targeting and making it an appealing target for RNAi-based therapeutic strategies. The clinical success of siRNA-mediated interventions critically depends upon the safety and efficacy of the delivery methods and agents. Delivery of siRNAs relevant to lung diseases has been attempted through multiple routes and using various
Arabidopsis ROS1 protein: is a DNA repair protein that represses homology-dependent transcriptional gene silencing by demethylating the target promoter DNA; amino acid sequence in first source
5-aza-2-deoxycytidine 2353-33-5 NMR spectrum, 5-aza-2-deoxycytidine H-NMR spectral analysis, 5-aza-2-deoxycytidine C-NMR spectral analysis ect.
Heterochromatin is a type of tightly-coiled chromosomal material that carries genes. Although heterochromatin is largely inert...
Custom siRNAs can be synthesized according to your sequence information, or use our complimentary siRNA design service. Up to 30-mer siRNA including a choice of 32 different 3 overhangs can be ordered with a variety of modification options for expanded specificity
The Sarma laboratory is interested in the mechanisms of epigenetic gene regulation, or how the dynamic modifications of the architecture of chromatin, the complex of DNA and proteins within the nucleus of our cells, impacts gene expression and cellul
Rowat, A. C. ; Weitz, D. A. Understanding epigenetic regulation: Tracking protein levels across multiple generations of cells. European Physical Journal-Special Topics 2009, 178, 71-80.
Even though photo ID and a $200 tax are required to get them, silencers are so popular that theres a nine-month wait to have a registration approved by the ATF.
Negative control siRNAs designed to target no known genes in human, mouse or rat. Recommended for determination of baseline cellular responses in RNAi experiments.
A new technique for turning off genes, which has proved strikingly effective and become a very hot topic in biology. It stands for RNA interference. Ani...
TY - JOUR. T1 - Prognostic Significance of Gremlin1 (GREM1) Promoter CpG Island Hypermethylation in Clear Cell Renal Cell Carcinoma. AU - van Vlodrop, Iris J. H.. AU - Baldewijns, Marcella M. L.. AU - Smits, Kim M.. AU - Schouten, Leo J.. AU - van Neste, Leander. AU - Van Criekinge, Wim. AU - van Poppel, Hein. AU - Lerut, Evelyne. AU - Schuebel, Kornel E.. AU - Ahuja, Nita. AU - Herman, James G.. AU - de Bruine, Adriaan P.. AU - van Engeland, Manon. PY - 2010/2. Y1 - 2010/2. U2 - 10.2353/ajpath.2010.090442. DO - 10.2353/ajpath.2010.090442. M3 - Article. VL - 176. SP - 575. EP - 584. JO - American Journal of Pathology. JF - American Journal of Pathology. SN - 0002-9440. IS - 2. ER - ...
Tumor‑specific promoter hypermethylation of large tumor suppressor, homolog 2 (LATS2), a tumor suppressor gene, has been investigated using methylation‑specific polymerase chain reaction (MSP) assays in different types of human cancer producing conflicting results. The aim of the present study was to evaluate the methylation status of the LATS2 promoter region using bisulfite sequencing with a next generation sequencer for breast cancer. In the 11 patients enrolled in the present study, the LATS2 promoter methylation index (MI) was uniformly high in tumor and normal tissues of the breast (median, 84.0 and 87.4%, respectively). The presence of LATS2 promoter hypermethylation was confirmed in isolated tumor cells and normal epithelial cells using the magnetic‑activated cell sorting method. In situ hybridization for LATS2 messenger RNA (mRNA) revealed that the mRNA expression of LATS2 was higher in normal epithelial cells, compared with tumor cells, however, it was not significantly ...
Keywords: Keywords: DNA methylation - Gene silencing - RNA-directed DNA methylation - RNA interference - Transposon.; Abbreviations: Ac, Activator; BAL, BALL; CMT, CHROMOMETHYLASE; DDM, DECREASE IN DNA METHYLATION; DRM, DOMAIN REARRANGED METHYLTRANSFERASE; En/Spm, Enhancer/Suppressor-mutator; MET, METHYLTRANSFERASE; MOP, MODIFIER OF PARAMUTATION; PAI, PHOSPHORIBOSYLANTHRANILATE ISOMERASE; PTGS, post-transcriptional gene silencing; RdDM, RNA-directed DNA methylation; RNAi, RNA interference; SUP, SUPERMAN; TGS, transcriptional gene silencing; TSI, transcriptionally silent information. Journal Article. 5263 words. Subjects: Biochemistry ; Molecular and Cell Biology ; Plant Sciences and Forestry ...
The role of DNA methylation in the control of mammalian gene expression has been the subject of intensive research in recent years, partly due to the critical role of CpG island methylation in the inactivation of tumour suppressor genes during the development of cancer. However, this research has also helped elucidate the role that DNA methylation plays in normal cells. At present, it is also clear that DNA methylation forms an important part of the normal cell-regulatory processes that govern gene transcription. Methylation, targeted at CpG islands, is an important part of the mechanisms that govern X-chromosome inactivation; it is also essential for the maintenance of imprinted genes and, at least in some cases, is critical in determining the cell-type-specific expression patterns of genes. Study of these examples will be important in identifying the mechanisms that control targeting of DNA methylation and how these processes are disrupted during disease pathogenesis.. ...
Aberrant CpG methylation changes occurring during tumour progression include the loss (hypomethylation) and gain (hypermethylation) of methyl groups. control. We have therefore demonstrated the ability of this technique, the identification of CGI exhibiting altered methylation patterns (ICEAMP), to isolate tumour-specific methylated GC-rich sequences. This will allow a comprehensive identification of methylation changes during tumourigenesis and will lead to a better understanding of the processes involved. INTRODUCTION The aberrant methylation of CpG dinucleotides has been widely reported during tumourigenesis in a variety of cancers (for review see 1). The alterations identified and their consequences include the loss of methyl groups, which is thought to buy 931409-24-4 increase chromosomal instability (2). Alternatively, the gain of methyl groups, particularly in CpG islands [CGIs: GC-rich regions of the genome, ~1 kb in length, originally characterised due to their lack of methylation (3)], ...
DESCRIPTION (provided by applicant): Epigenetic changes, particularly alterations in DNA methylation, contribute to oncogenesis in at least two respects. First, overall DNA methylation is reduced in tumors, which leads to aberrant gene activation and genomic instability. Second, CpG island promoters become hypermethylated, which leads to transcriptional silencing and the functional inactivation of tumor suppressor genes. In addition to changes in DNA methylation, other important epigenetic changes have been observed in human cancer, including alterations in histone modification patterns and histone modifying enzymes. Our long-term objective is to understand the molecular mechanisms that initiate and maintain abnormal epigenetic states in human cancer. To meet this objective, we are utilizing cancer/germ-line (CG) antigen genes as models. CG antigens are an intriguing gene family whose aberrant expression in human cancer appears to result from epigenetic deregulation. In addition, CG antigens are ...
Specific gene knock-down in post-natal cells by siRNA molecules has immense potential as a research and therapeutic tool. While direct effects have been clearly demonstrated in siRNA-transduced cells, we investigated a possible "bystander effect" whereby siRNAs transfer between transduced and non-transduced (NT) primary neonatal rat ventricular myocytes (NRVMs) via gap junctions. To enable siRNA expression in NRVMs, lentiviral vectors (LV) encoding short-hairpin (sh)RNAs, which are processed to siRNAs, were generated. Two populations of LV-transduced NRVMs were produced; one expressing GFP and the other co-expressing a second reporter plus a siRNA designed to knock-down GFP. Following 7 days co-culture of these populations, flow cytometry revealed a 35% reduction in the mean GFP fluorescence intensity and real-time PCR confirmed GFP mRNA knock-down. To explore dependence of this effect on gap junctions, we co-transduced cells with a LV encoding a dominant-negative connexin43 mutant (Cx43Δ) as a ...
DNA methylation (global and gene-specific) has been reported as an epigenetic mechanism that could be involved in the pathogenesis of type 2 diabetes mellitus (T2DM). Furthermore, epigenetic therapy has been suggested as a future possibility for T2DM treatment. Epigenetic changes illustrate the environmental link of the disease. Since some of the epigenetic modifications can be reversed, they could be used as potential therapeutic targets. The aim of the systematic review will be to synthesise the available evidence pertaining to the link between DNA methylation and T2DM. The systematic review will evaluate characteristics of reported studies such as the source of DNA used, methods of quantifying DNA methylation and the participants demographics (age, gender, race and adiposity). We will conduct a narrative synthesis of data, and if there are an adequate number of sufficiently homogenous studies, we will consider performing a meta-analysis. The review will evaluate if the levels of DNA methylation are
The discovery of double-stranded RNA-mediated gene silencing has rapidly led to its use as a method of choice for blocking a gene, and has turned it into one of the most discussed topics in cell biology. Although still in its infancy, the field of RNA interference has already produced a vast array of results, mainly in Caenorhabditis elegans, but recently also in mammalian systems. Micro-RNAs are short hairpins of RNA capable of blocking translation, which are transcribed from genomic DNA and are implicated in several aspects from development to cell signaling. The present review discusses the main methods used for gene silencing in cell culture and animal models, including the selection of target sequences, delivery methods and strategies for a successful silencing. Expected developments are briefly discussed, ranging from reverse genetics to therapeutics. Thus, the development of the new paradigm of RNA-mediated gene silencing has produced two important advances: knowledge of a basic cellular ...