Huntington disease is a neurodegenerative disease characterized by a polymorphic tract of polyglutamine repeats in exon 1 of the huntingtin protein, which is thought to be responsible for protein aggregation and neuronal death. The polyglutamine tract is preceded by a 17-residue sequence that is intrinsically disordered. This region is subject to phosphorylation, acetylation and other post-translational modifications in vivo, which modulate its secondary structure, aggregation and, subcellular localization. We used Molecular Dynamics simulations with a novel Hamiltonian-replica-exchange-based enhanced sampling method, SWISH, and an optimal combination of water and protein force fields to study the effects of phosphorylation and acetylation as well as cross-talk between these modifications on the huntingtin N-terminus. The simulations, validated by circular dichroism, were used to formulate a mechanism by which the modifications influence helical conformations. Our findings have implications for
Post-translationally modified proteins make up the majority of the proteome and establish, to a large part, the impressive level of functional diversity in higher, multi-cellular organisms. Most eukar
Find great deals for Analysis of Protein Post-Translational Modifications by Mass Spectrometry by John R. Griffiths, Richard D. Unwin (Hardback, 2016). Shop with confidence on eBay!
The N-terminal tail of CENP-A is highly divergent from other H3 variants. Canonical histone N-termini are hotspots of conserved post-translational modification; however, no broadly conserved modifications of the vertebrate CENP-A tail have been previously observed. Our lab has identified novel post-translational modifications on human CENP-A N-termini using high-resolution MS. These include the trimethylation of Gly1 at the alpha-amino position and side-chain phosphorylation of Ser16 and Ser18. CENP-A is subjected to constitutive initiating methionine removal, similar to other H3 variants. The nascent N-terminal residue Gly1 becomes trimethylated on the α-amino group. We identified the methyltransferase NRMT as the enzyme responsible for modifying the CENP-A amino terminus. Methylation occurs in the pre-nucleosomal form and marks the majority of CENP-A nucleosomes. Serine 16 and 18 become phosphorylated in pre-nucleosomal CENP-A and are phosphorylated on asynchronous and mitotic nucleosomal ...
Histones and their variants are subjected to several post-translational modifications (PTMs). Histones PTMs play an important role in the regulation of gene expression and are critical for the development and progression of many types of cancer, including breast cancer. In this study, we used two-dimensional TAU/SDS electrophoresis, coupled with mass spectrometry for a comprehensive profiling of histone PTMs in breast cancer cell lines.Proteomic approach allowed us to identify 85 histone PTMs, seventeen of which are not reported in the UniProt database. Western blot analysis was performed to confirm a peculiar pattern of PTMs in the sporadic and hereditary breast cancer cell lines compared to normal cells. Overlapping mass spectrometry data with western blotting results, we identified, for the first time to our knowledge, a tyrosine phosphorylation on histone H1, which is significantly higher in breast cancer cells. Additionally, by inhibiting specific signaling paths, such as PI3K, PPARγ and FAK
Nucleosome ELISA (NU-ELISA) is a sensitive and quantitative method to detect global patterns of post-translational modifications in...
In animals NO has been shown to play a key role in many important physiological process such as relaxation of vascular smooth muscle, neurotransmission, inflammation and immune function (Ignarro & Buga, 1987; ODell et al., 1991; Eiserich et al., 1998). Similarly, NO signalling in plants modulates a variety of physiological systems, from adaptive responses to germination, root growth and dynamics of stomatal aperture control. A significant emerging theme is the regulation of these processes through post-translational protein modifications, mainly metal nitrosylation, S-nitrosylation and tyrosine nitration (Besson-Bard et al., 2008). Metal nitrosylation is characterized by the formation of a NO-metal-containing protein and is best exemplified by the reaction between NO and haemoglobin (Hb), which controls vascular oxygen distribution. Metal nitrosylation also has a well characterized role during the activation of soluble guanylate cyclase (sGC) in animal cells, a classical route for the transfer ...
Asparagine-linked glycosylation is one of the most common protein modification reactions in eukaryotic cells, occurring on N-(x≠P)-T/S/C consensus sequons on newly synthesized proteins in the lumen of the rough endoplasmic reticulum (RER). Transfer of the preassembled oligosaccharide (GlcNAc2Man9Glc3) from a dolichol pyrophosphate carrier to sequons is mediated by the oligosaccharyltransferase (OST). Although N-glycosylation is often described as a post-translational protein modification reaction, most N-linked glycans are added to ribosome-bound nascent polypeptides as the protein is passing through the protein translocation channel into the lumen of the RER. A cotranslational mode of N-linked glycosylation ensures that addition of glycan occurs before protein folding, thereby relieving the restriction that sequons reside on surface-exposed loops or within disordered protein segments that can access the OST active site (Lizak et al., 2011).. The OST is a hetero-oligomeric integral membrane ...
Molecular Reproduction and Development takes an integrated, systems-biology approach to understand the dynamic continuum of cellular, reproductive, and developmental processes. This journal fosters dialogue among diverse disciplines through primary research communications and educational forums, with the philosophy that fundamental findings within the life sciences result from a convergence of disciplines.. Increasingly, readers of the Journal need to be informed of diverse, yet integrated, topics impinging on their areas of interest. This requires an expansion in thinking towards non-traditional, interdisciplinary experimental design and data analysis. For example, biologists need to know how nanodevices might be used, while bioengineers need to know how post-translational protein modifications affect developmental mechanisms. The Journal will provide a means for readers to integrate divergent scientific disciplines into their current and future research. Readers will turn to Molecular ...
Demonstrates the first synthesis of histones, nucleosome core particles and defined nucleosomes arrays bearing this important post-translational modification, and demonstrates using single molecule FRET that H3K56 acetylation increases DNA breathing on nucleosomes. This paper demonstrates the power of creating designer nucleosomes to address problems in chromatin biology. More broadly, it demonstrates the power of genetically installing post translational modifications for asking previously un-addressable questions about biological regulation. ...
Nitric oxide (NO) is a free-radical product of mammalian cell metabolism that plays diverse and important roles in the regulation of cell function. Biological actions of NO arise as a direct consequence of chemical reactions between NO or NO-derived species and protein targets. Reactions of NO with transition metals in target proteins have garnered the most attention to date as the principal mechanism of NO signaling; nonetheless, S-nitrosylation of protein Cys residues is rapidly moving to center stage in importance. In general, however, there has been a delay in adequate appreciation of the role of S-nitrosylation in biological signaling by NO. This lag is attributed to a poor understanding of the basis for selective targeting of NO to particular thiols, and methodological limitations in accurately quantifying this modification--recent breakthroughs in concepts and methods diminish these barriers. Here, we consider the wheres and whys of protein S-nitrosylation and its basis for specificity. ...
Phosphorylation is a crucial post-translational protein modification mechanism with important regulatory functions in biological systems. It is catalyzed by a group of enzymes called kinases, each of which recognizes certain target sites in its substrate proteins.
The Proteomics Core Facility at the Frankfurt location is an initiative of the DKTK and is equipped with three Q Exactive mass spectrometers from Thermo Fisher (one Q Exactive, one Q Exactive Plus and one Q Exactive HF instrument). The available technology can be used to e.g. identify and quantify protein expression patterns, post-translational protein modifications such as phosphorylation, acetylation and ubiquitination, and protein complexes.. This makes it possible to conduct a comprehensive characterisation of oncogenic mechanisms at the protein level, which includes mapping of oncogenic signal transduction processes. The technical advances made in recent years mean that it is now possible to identify and quantify in relative terms several thousand proteins from just a few micrograms of protein. The main activities of the Proteomics Core Facility relate to translational research topics in the field of acute leukaemia, lymphoma, lung cancer, rectal cancer and brain tumours. The research uses ...
Medical & Life Sciences (Biochemistry), Manipulation and analysis of proteins; Research areas include the experimental analysis of enzyme mechanisms, post-translational protein modifications, proteomics, and protein-nucleic acid interactions studied in the biological context of cell cycle control, chromatin regulation and renewable energy research ...
The transfer of macromolecules such as nucleic acids and proteins to solid-phase membranous support is known as blotting. Fragments of DNA and RNA molecules separated by gel electrophoresis are transferred to a nylon or nitrocellulose membrane in a process termed as Southern and Northern blotting, respectively. Southern blotting was introduced by Edwin Southern in 1975 as a method to detect specific sequences of DNA in DNA samples. The other blotting techniques emerged from this method have been termed as Northern (for RNA), Western (for proteins), Eastern (for post-translational protein modifications) and Southwestern (for DNA-protein interactions) blotting.. Southern and Northern blotting protocols involve the following major steps:. ...
Post-Translational Modification - Most proteins undergo some form of modification following translation. These modifications result in mass changes that are detected during analysis. Post-translational modifications such as glycosylation, phosphorylation, and sulfation, to name a few, serve many functions. As a result, the analysis of proteins and their post-translational modifications is particularly important for the study of diseases where multiple genes are known to be involved, such as heart disease, cancer and diabetes.
With the rapidly increasing use of proteins as biotherapeutics to treat diseases, the characterization of these large molecules using mass spectrometry has become a highly attractive field of research. A particular area of research is the identification and characterization of protein post-translational modifications. Disulfide bonds and glycosylation are among the most critical protein post-translational modifications (PTMs), as they play vital roles in maintaining the proper protein folding, structure, and functions. These two PTMs are particularly important in the development and characterization of monoclonal antibody-based drugs, which are the most prevalent protein therapeutics in the market. Among the four classes of immunoglobulins (IgGs), the disulfide connectivity of IgG1, IgG2 and IgG4 have been effectively studied, and IgG2 and IgG4 have been shown to have disulfide bond-mediated isomers due to alternative disulfide bond connectivity. However, no studies to investigate the presence ...
Ngn3 is recognized as a regulator of pancreatic endocrine formation, and Notch signaling as an important negative regulator Ngn3 gene expression. By conditionally controlling expression of Ngn3 in the pancreas, we find that these two signaling components are dynamically linked. This connection involves transcriptional repression as previously shown, but also incorporates a novel post-translational mechanism. In addition to its ability to promote endocrine fate, we provide evidence of a competing ability of Ngn3 in the patterning of multipotent progenitor cells in turn controlling the formation of ducts. On one hand, Ngn3 cell-intrinsically activates endocrine target genes; on the other, Ngn3 cell-extrinsically promotes lateral signaling via the Dll1,Notch,Hes1 pathway which substantially limits its ability to sustain endocrine formation. Prior to endocrine commitment, the Ngn3-mediated activation of the Notch,Hes1 pathway impacts formation of the trunk domain in the pancreas causing multipotent ...
Protein glycation is a spontaneous PTM of the proteome focused mainly on N-terminal and lysine side chain amino groups by glucose forming fructosa- mine residues and on guanidino groups of arginine residues forming mainly MG-derived hydroimidazolone residues. The latter appears to be most functionally damaging in physiological systems. Glycation is a relatively labile PTM, and so customized preanalytical processing is required to avoid compromising mass spectrometric analysis outcomes. ETD fragmentation has a clear advantage for the analysis of the fructosamine proteome, whereas CID, HCD, and ETD may be used for arginine-based dihydroxyimidazolidine/hydroimi- dazolone detection. Robust procedures are available for the detection and quantitation of total glycation adducts in protein extracts, and these may be combined with proteomics analysis for added security of findings - particularly as it is still challenging to achieve high sequence coverage in proteomics experiments. LC-MS/MS quantitative ...
Step change for this strategy was achieved by introduction of a dimethylation step posttryptic digest to block free (N-terminal, lysine-e) amines thus increasing the difference in basicity between N-acetylated and the rest of peptides in the sample. One-step purification of N-acetylated peptides is achieved by solid-phase extraction, using SCX in batch mode. A key benefit of this approach is that it can be utilized with stable isotope-labeled dimethylation reagents for relative quantification, an approach which has found application to distinguish protein isoforms that are N-terminally acetylated but differ in N-terminal amino acid sequence, for example, p-actin/y-actin isoforms [111]. ...
Enrichment methods to facilitate detection and quantitation of PTM proteins are a common strategy in proteomics. A boronate affinity chromatography method has been used for the fructosamine proteome based on the binding of the cis-1,2-diol structure of fructosamine-modified proteins, with subsequent release from the boronate affinity matrix with weak acid. Although some enzymatically glycosylated proteins contain cis-1,2-diol moieties, steric effects, proximate negatively charged groups, and acetylation limit the retention and interference in this method by glycoproteins [98]. A similar affinity method is used in the routine separation of hemoglobin in clinical chemistry to quantify glycated hemoglobin HbA1c for the assessment of glycemic control in diabetes [99]. Boronate affinity enrichment of protein glycated by glucose was employed in a study of glycated proteins in human plasma and red blood cells, and 7749 unique glycated peptides corresponding to 3742 unique glycated proteins were ...
The aforementioned considerations are features relating to the rate of formation of glycation adducts. FL and MG-H1 residues have half-lives of ca. 25 and 12 days, respectively [19, 106], which exceed the half-lives of most human proteins (median half-life of 1.9 days [107]). Therefore, for many proteins, the steady-state extent of protein glycation is also influenced by the half-life of the protein. Hence, early studies found that the extent of glycation by glucose of several proteins in vivo was linked to the protein half-life [108]. Since glycation leads to protein distortion and misfolding, it is also expected that glycated proteins are targeted for cellular proteolysis and have an unusually decreased halflife. This remains to be determined in robust unfocused proteome dynamics studies. The level of FL and N-terminal fructosamine residues in cellular proteins is also influenced by enzymatic removal and repair by F3PK [109]. F3PK has different specific activity for FL residues in different ...
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E-cadherin is synthesized as a precursor and then undergoes cleavage by proprotein convertases. This processing is essential for E-cadherin maturation and cell adhesion. Loss of cell adhesion causes detachment-induced apoptosis- anoikis. Anoikis can be inhibited despite loss of cell-matrix interactions by preserving E-cadherin mediated cell-cell adhesion. Conversely, acute loss of E-cadherin sensitizes cells to apoptosis by unknown post-translational mechanisms. In response to drug treatment of breast cancer cells, our analysis revealed that two independent modifications of E-cadherin inhibit its cell surface transport. Firstly, O-linked beta-N-acetylglucosamine (O-GlcNAc) modification of the cytoplasmic domain retains E-cadherin in the endoplasmic reticulum. Secondly, incomplete processing by proprotein convertases arrests E-cadherin transport late in the secretory pathway. We demonstrated these E-cadherin modifications (detected by specific lectins and antibodies) do not affect binding to ...
Large‐scale identification of PTMs across multiple species has opened the door to comparative studies regarding the evolutionary conservation of the modification sites, interactions and function. These studies have primarily focused on protein phosphorylation given its broad functional role and well established detection methods. Most of the comparative analyses performed to date have studied the conservation of the modified residues in alignments of orthologous proteins (Holt et al, 2009; Landry et al, 2009; Nguyen Ba & Moses, 2010; Gray & Kumar, 2011). There is some debate regarding the extent of conservation: some studies report little to no conservation of the modified residues when compared to unmodified amino‐acids (Holt et al, 2009; Landry et al, 2009; Nguyen Ba & Moses, 2010), whereas others observe a significant constraint due to the phosphorylation (Gray & Kumar, 2011). Overall, a reconciled view on these finding is that phosphorylated residues show a significant but small increase ...
Imagine you are doing XIC based label free quan on sample 1 and sample 2. In sample 1 you find peptide HAPPYK with an intensity of 1e6 that elutes at 23.4 minutes. In sample B, you only find HAPPYK at that retention time at almost baseline, but at 10.8 minutes you find HAPPphospho-YK with an intesity of 8e5. Unless youve got some awesome tools that I dont have for global analysis of this type, get ready to buckle down for a fun filled afternoon of manually linking your modified and unmodified variants in that Excel sheet! (PD 2.0/2.1 can make the job a little easier for you -- see video 22 here, but you still have to do a lot of manual work ...
ziyuBio offers hundreds of peptide modifications to meet your custom peptide needs. These peptide modifications can be used to create synthetic peptide with the exact conformation or characteristics needed for specific applications. Large numbers of modified amino acids are focus on post-translation modification (PTM) that naturally occur in vivo, while others are pharmacologically modified or stable isotope labeled. Additionally, tags, protein or oligonucleotides can be chemically conjugated to these peptides through ziyuBio. With many years of experience in providing modified peptide synthesis, we are your best choice for producing custom modified peptides on time and on budget. Our peptide modification services include but are not limited to the following:. ■ Fluorophores and Quenchers: Emitting and Quenching dyes for FRET and other dyes. ■ Attachment Chemistry: Linkers, Spacers and Polyethylene Glycol (PEG) modifications. ■ Unnatural Amino Acids: D-stereoisomers, Unnatural and special ...
To characterize the properties of the NvHsTRPA channel, we expressed it in HEK293 cells. Localization of the V5 and His epitope-tagged NvHsTRPA protein showed a staining pattern at the plasma membrane, demonstrating that it reaches to the cell surface (Fig. 5A). Nevertheless, some proteins are present in the cytoplasm as well. The molecular weight of the tagged protein was approximately 112 kDa, which is slightly larger than expected (105 kDa) from the amino acid sequence. The protein size was constant in the presence of tunicamycin, an inhibitor of N-glycosylation (Fig. 5B), indicating that NvHsTRPA does not contain N-glycans unlike the vertebrate TRPV1, 4, 5, and TRPC3 and 6 as reported [42]. The partial denature of NvHsTRPA (60°C for 5 min) may result in the aberrant migration through 6% SDS-PAGE gel which makes the correct estimation of protein size difficult. Nevertheless, the possibility that NvHsTRPA undergoes the other post-translational modifications can not be ruled out. Patch-clamp ...
Phosphorylation is one of the most important post-translational modification. Phosphorylation is involved in multiple biological process such as DNA damage and repair, transcrip- tion regulation, and metabolism. In human proteome, three types of major residue in the substrate; serine(S), threonine(T), and tyrosine (Y) is phosphorylated by their responsible kinase. Streaming motion of phosphorylation constructs an signal transaction network of the living cell.. Resent achievements in the area of mass spectrometry based proteomics accomplished in determining the phosphorylated residue of the protein in a massive scale. On the other hand, the global picture of signal network driven by phosphorylation still remains unclear, due to the lack of information of kinase-substrate pairs. To work out with this problem, computational approaches has been applied. While various numbers of computational predictors such as Scansite, NetworKIN, PPRED are available, there still remains a interruption in ...
We produce custom antibodies against PTMs such as phosphorylation, acetylation, and methylation as well as Ubiquitinylation or SUMOylation.
Forkhead box O3, also known as FOXO3 or FOXO3a, is a human protein encoded by the FOXO3 gene. FOXO3 belongs to the O subclass of the forkhead family of transcription factors which are characterized by a distinct fork head DNA-binding domain. There are three other FoxO family members in humans, FOXO1, FOXO4 and FOXO6. These transcription factors share the ability to be inhibited and translocated out of the nucleus on phosphorylation by proteins such as Akt/PKB in the PI3K signaling pathway (aside from FOXO6, which may be constitutively nuclear). Other post-translational modifications including acetylation and methylation are seen and can result in increased or altered FOXO3a activity. This protein likely functions as a trigger for apoptosis through upregulation of genes necessary for cell death, such as Bim and PUMA, or downregulation of anti-apoptotic proteins such as FLIP. Gopinath et al.(2014) demonstrate a functional requirement for FOXO3 as a regulator of Notch signaling pathway (an ...
Fibroblast Activation Protein (FAP) is a cellXsurface anchored dimeric protease, closely related to Dipeptidyl Peptidase (DPP) 4. This atypical serine protease has both dipeptidyl peptidase and endopeptidase activities, cleaving substrates at a postXproline bond. FAP expression is difficult to detect in nonXdiseased adult organs, but is greatly up regulated in sites of tissue remodelling, which includes liver fibrosis, lung fibrosis, atherosclerosis, arthritis, tumours and embryonic tissues. Due to its restricted expression pattern and dual enzymatic activities, FAP is emerging as a unique therapeutic target. However, methods to exploit and target this protease are advancing more rapidly than knowledge of the fundamental biology of FAP. This thesis aims to rectify this imbalance, emphasising the need to better define the substrate repertoire and downstream effects of FAP enzyme activity to elucidate the role of this protease in biological and pathological processes. In this study, primary mouse ...
STATIN INHIBITION OF MACROPHAGE INTEGRIN-INDUCED RAC2-MYOSIN IIA INTERACTION: AN ANTI-INFLAMMATORY EFFECT. Kenneth E. Ike, Alan Morrison, and Jeffrey R. Bender. Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University, School of Medicine, New Haven, CT. HMG-CoA reductase inhibitors (statins) are pharmaceuticals that are utilized for the treatment of lipid disorders along with the primary and secondary prevention of coronary heart disease. HMG-CoA reductase is the rate-limiting enzyme in cholesterol synthesis, converting HMG-CoA to mevalonate. The isoprenoid products, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), are derived from the mevalonate pathway and serve as substrates in the prenylation of 2% of cellular proteins including the Rho family of low molecular weight G-proteins which mediate multiple cellular signals. Prenylation is an important post-translational modification of proteins that plays a role in the subcellular localization of proteins
Perform Glycan and Glycopeptide Qualitative Analysis, Glycan Structure Prediction & Multi stage Mass Spectrometry (MSn) data analysis using accurate ranking mechanism.
Is this a trick question? :) Sudheendra Rao N R ,sudhee26 from gmail.com, wrote in message news:mailman.491.1202159543.2451.methods from net.bio.net... , Hi, , can somebody tell me what changes would occur to the molecular weight of a , protein being run in a denaturing PAGE after it undergoes Post , translational , modification? , like sumoylation can increase mol weight by 11kD. , , Sudheendra. , , -- , Think before agree , Think before you nod , but STOP thinking , and You Are God ...
H1S186ph. H1.4 serine 186 (reported as H1S187) phosphorylation is preferentially associated with active rDNA promoters and enriched at hormone response element (PMID: 20439994). ...
Authors: Georges Khoury, Talia M Mota, Shuang Li, Carolin Tumpach, Michelle Y Lee, Jonathan Jacobson, Leigh Harty, Jenny L Anderson, Sharon R Lewin, Damian FJ Purcell
C.Post-Translational Modification Proteomics--phosphoproteome identification Protein post-translational modification (PTM) increases the functional diversity of the proteome either by the covalent addition of chemical moieties or functional groups, or by the proteolytic cleavage of regulatory subunits or the degradation of protein complexes. Many large-scale post-translational modification studies have recently been performed on various organisms, and phosphorylation, acetylation, methylation, and glycosylation are among the most intensively studied PTM proteomes. Protein phosphorylation is an ubiquitous post-translational modification, essential to many physiological and biological processes and cellular events. Phosphoproteomic analysis provides identification of phosphorylated proteins and peptides, providing key data for understanding their biological functions. This proteomic method has greatly enhanced our understanding of cellular phosphoproteins and their dynamic regulatory mechanisms in ...
Nature provides an abundant source of functional proteins for designing new systems. To date, chromatin proteins are an untapped resource. A class of chromatin proteins, known as "effectors," have the remarkable ability to discriminate and bind to specific post-translational modifications of target proteins called histones. Can a synthetic protein device be engineered to read histone modifications? Can we use this type of device as a new tool to monitor changes in histone modifications in single living cells? Accomplishing these goals will allow scientists to probe histone modification at unprecedented resolution, thus furthering our understanding of the dynamics of histone modifications associated with cancer and normal cell development. ...
E3 protein ligase that mediates ufmylation, the covalent attachment of the ubiquitin-like modifier UFM1 to substrate proteins, a post-translational modification on lysine residues of proteins that may play a crucial role in a number of cellular processes. Mediates DDRGK1 ufmylation and may regulate the proteasomal degradation of DDRGK1 and CDK5RAP3 thereby modulating NF-kappa-B signaling (PubMed:20018847, PubMed:20164180, PubMed:20228063, PubMed:25219498). May also through TRIP4 ufmylation play a role in nuclear receptors-mediated transcription (PubMed:25219498). May play a role in the unfolded protein response, mediating the ufmylation of multiple proteins in response to endoplasmic reticulum stress (PubMed:23152784).
YM-216391, an autitumor natural product, represents a new class of cyclic peptides containing a polyoxazolethiazole moiety, Herein we describe its gene cluster encoding the biosynthetic paradigm featuring a ribosomally synthesizing procursor peptide followed by a series of novel posttranslational modifications which include (1) cleavage of both N-terminal leader peptide and C-terminal extension peptide and cyclization in a head-to-tail fashion, (ii) conversion of an L-Ile to D-allo-Ile, and (iii) beta-hydroxylation of Phe by a P450 monooxygenase followed by further heterocyclization and oxidation to form a phenyloxazole moiety. The cluster was heterologously expressed in Streptomyces lividans to bypass difficult genetic manipulation. Deletion of the ymR3 gene, encoding a putative transcriptional regulator, increased the YM-216391 yield about 20-fold higher than the original yields for the heterologous expression of wild-type cluster, which set the stage for further combinatorial biosynthesis ...
The NF-κB family of transcription factors play a central role in the inducible expression ofinflammatory genes during the immune response, and the proper regulation of these genes is acritical factor in the maintenance of immune homeostasis. The chromatin environment atstimulus-responsive NF-κB sites is a major determinant in transcription factor binding, anddynamic alteration of the chromatin state to facilitate transcription factor binding is a keyregulatory mechanism. NF-κB is in turn able to influence the chromatin state through a variety ofmechanisms, including the recruitment of chromatin modifying co-activator complexes such asp300, the competitive eviction of negative chromatin modifications, and the recruitment ofcomponents of the general transcriptional machinery. Frequently, the selective interaction withthese co-activators is dependent on specific post-translational modification of NF-κB subunits.Finally, the mechanisms of inducible NF-κB activity in different immune cell types seem to
Influenza A virus (IAV) targets the ciliated epithelium of conducting airways through interaction of the viral envelope protein hemagglutinin (HA) with cell surface glycoproteins or glycolipids containing terminal sialic acid residues. Following IAV internalization by endocytosis, HA leads to fusion of the viral and cellular membranes by virtue of irreversible conformational changes into the HA molecule triggered by the mildly acidic pH within the virion-containing endosome, allowing the viral RNA genome to get inside the cytoplasm and thus instruct the cell to make new viral particles. The HA spike on the viral envelope is a homotrimeric type I integral membrane glycoprotein, where each of the mature monomers results from extensive post-translational modifications (i.e. trimming of N-linked carbohydrate chains, terminal glycosylation, sulfation, fatty acylation) during transport en route from the endoplasmic reticulum to the plasma membrane. Although current IAV vaccination programs in humans ...
The Johns Hopkins University School of Medicine. Epigenetics, the study of heritable changes in gene function not due to mutations in the DNA sequence, provides the syntax, structural organization, developmental context and functional programs that give meaning to the sequence of letters in the genomes "Book of Life.". The broad applicability of epigenetics might surprise some researchers. The last decade has brought several profound and exciting insights into epigenetic mechanisms and the application of epigenetics to biology and medicine generally. For example, it is now known that histones show specific post-translational modifications that contain information and are at the heart of transcriptional regulation. And researchers have discovered that problems with DNA methylation and genomic imprinting can affect cancer risk and progression and brain and immune system disorders. But each new discovery reveals that epigenetic control of gene regulation and gene expression will have an impact ...
Tweedie-Cullen RY, Reck JM, Mansuy IM (2009) Comprehensive mapping of post-translational modifications on synaptic, nuclear, and histone proteins in the adult mouse brain. J Proteome Res 8, 4966-82 ...
Microorganisms have evolved mechanisms that enable them to grow and rapidly adapt to changing environmental conditions. Regulation of protein activity can occur at transcriptional, translational, and/or post-translational levels. Transcriptional and translational control are slow and have high energy costs due to de novo synthesis of proteins (i.e. transcription, translation, and protein-folding processes). Conversely, protein post-translational modifications drive adaptive cellular responses more efficiently by adding or removing functional groups from specific protein residues (1). Among the post-translational modifications that regulate protein functionality, phosphorylation is by far the most studied in bacteria (2, 3).. Two-component systems involve the phosphorylation of histidine and aspartate residues and were the first studied bacterial signal transduction mechanisms (3). Pioneering studies in Escherichia coli and Bacillus subtilis demonstrated extensive serine, threonine, and tyrosine ...
The small ubiquitin related modifier (SUMO)-mediated posttranslational protein modification is widely conserved among eukaryotes. Similar to ubiquitination, SUMO modifications are attached to the substrate protein through three reaction steps by the E1, E2 and E3 enzymes. To date, multiple families of SUMO E3 ligases have been reported in yeast and animals, but only two types of E3 ligases have been identified in Arabidopsis: SAP and Miz 1 (SIZ1) and Methyl Methanesulfonate-Sensitivity protein 21 (MMS21)/HIGH PLOIDY 2 (HPY2), hereafter referred to as HPY2. Both proteins possess characteristic motifs termed Siz/PIAS RING (SP-RING) domains, and these motifs are conserved throughout the plant kingdom. Previous studies have shown that loss-of-function mutations in HPY2 or SIZ1 cause dwarf phenotypes and that the phenotype of siz1-2 is caused by the accumulation of salicylic acid (SA). However, we demonstrate here that the phenotype of hpy2-1 does not depend on SA accumulation. Consistently, the expression
Nitric oxide can modify cysteine residues on proteins and produce an S-nitrosylated derivative (see the review by Lane et al.). Gu et al. report that such a modification of matrix metalloproteinase-9 (MMP-9) activates the enzyme. MMP-9 nitrosylation and activation were observed in rodent brain tissue upon stroke, and treatment of cultured neurons with NO-activated MMP-9 caused apoptosis. This activation pathway may contribute to neuronal cell death that is associated with the extracellular matrix disruption observed in cerebral ischemia and neurodegenerative diseases. P. Lane, G. Hao, S. S. Gross, S-Nitrosylation is emerging as a specific and fundamental posttranslational protein modification: Head-to-head comparison with O-phosphorylation. Sciences STKE (2001), http://stke.sciencemag.org/cgi/content/full/sigtrans;2001/86/re1 [Abstract] [Full Text] Z. Gu, M. Kaul, B. Yan, S. J. Kridel, J. Cui, A. Strongin, J. W. Smith, R. C. Liddington, S. A. Lipton, S-Nitrosylation of matrix ...
Background: Reactive species have been regarded as by-products of cellular metabolism, which cause oxidative damage contributing to aging and neurodegenerative diseases. However, accumulated evidence support the notion that reactive species mediate intracellular and extracellular signals that regulate physiological functions including posttranslational protein modifications. Cysteine thiol groups of proteins are particularly susceptible to oxidative modifications by oxygen, nitrogen and sulfur species generating different products with critical roles in the cellular redox homeostasis. At physiological conditions, reactive species can function not only as intracellular second messengers with regulatory roles in many cellular metabolic processes but also as part of an ancestral biochemical network that controls cellular survival, regeneration, and death ...
We invite submissions pertaining to protein structure, function, and stability. Studies that utilize experimental or computational approaches are welcome, which may include structural or functional analysis, engineering of new proteins by structure-based design, effects of post-translational modifications, and analysis of protein conformational stability among other topics. Submissions that focus on the mechanisms of protein folding, misfolding, and post-translational modifications are particularly welcome.. ...