• gene
  • My data suggest that during wildtype sperm development, this HP1 gene primes the paternal DNA for embryonic mitosis. (upenn.edu)
  • DNA packaging initiation of Salmonella bacteriophage P22: determination of cut sites within the DNA sequence coding for gene 3. (mysciencework.com)
  • The region of packaging initiation is located within the sequence coding for gene 3. (mysciencework.com)
  • Supercoiling is important in a number of biological processes, such as compacting DNA, and by regulating access to the genetic code, DNA supercoiling strongly affects DNA metabolism and possibly gene expression. (wikipedia.org)
  • DNA supercoiling is important for DNA packaging within all cells, and seems to also play a role in gene expression. (wikipedia.org)
  • and BRCA1, another DNA-repair gene. (wikipedia.org)
  • In that year, while teaching a theoretical and laboratory course at the Cuban Center for Genetic Engineering and Biotechnology, he introduced the technique of DNA cloning in Cuba, which led to the establishment of the first sugar cane gene library. (wikipedia.org)
  • During gene expression, the DNA is first copied into RNA. (wikipedia.org)
  • A more likely source of cellular plasticity is through the Regulation of gene expression, such that while two cells may have near identical DNA, the differential expression of certain genes results in variation. (wikipedia.org)
  • And, while DNA binding transcription factors provide a mechanism for specific control of cellular responses, a model where DNA binding transcription factors are the sole regulators of gene activity is also unlikely. (wikipedia.org)
  • For example, in a study of Somatic-cell nuclear transfer, it was demonstrated that stable features of differentiation remain after the nucleus is transferred to a new cellular environment, suggesting that a stable and heritable mechanism of gene regulation was involved in the maintenance of the differentiated state in the absence of the DNA binding transcription factors. (wikipedia.org)
  • With the finding that DNA methylation and histone modifications are stable, heritable, and also reversible processes that influence gene expression without altering DNA primary structure, a mechanism for the observed variability in cell gene expression was provided. (wikipedia.org)
  • Genomic modifications that alter gene expression that cannot be attributed to modification of the primary DNA sequence and that are heritable mitotically and meiotically are classified as epigenetic modifications. (wikipedia.org)
  • Since H2A packages DNA molecules into chromatin, the packaging process will affect gene expression. (wikipedia.org)
  • In this model, the braconid and ichneumonid wasps packaged genes for these functions into the viruses-essentially creating a gene-transfer system that results in the caterpillar producing the immune-suppressing factors. (wikipedia.org)
  • Eukaryotes
  • Because the length of DNA can be thousands of times that of a cell, packaging this genetic material into the cell or nucleus (in eukaryotes) is a difficult feat. Supercoiling of DNA reduces the space and allows for DNA to be packaged. (wikipedia.org)
  • In eukaryotes, DNA supercoiling exists on many levels of both plectonemic and solenoidal supercoils, with the solenoidal supercoiling proving most effective in compacting the DNA. (wikipedia.org)
  • The spermatozoon is characterized by a minimum of cytoplasm and the most densely packed DNA known in eukaryotes. (wikipedia.org)
  • molecules
  • The distance between the two fluorescent molecules changes as the DNA unwraps and rewraps, allowing the process to be precisely measured. (blogspot.com)
  • In that study, Sytox Orange (an intercalating dye), has been used to induce supercoiling on surface tethered DNA molecules. (wikipedia.org)
  • epigenetics
  • But they are just beginning to learn about how changes to these non-DNA structures can affect development and health--a field known as epigenetics--and how they are regulated. (medindia.net)
  • These modifications were termed epigenetic, from epi "on top of" the genetic material "DNA" (Epigenetics 1). (wikipedia.org)
  • H2A has been correlated with DNA modification and epigenetics. (wikipedia.org)
  • sequence
  • Five percent of FSHD-affected individuals have array lengths, longer than 10 copies (the threshold for chromatin relaxation) of the DNA sequence in question making them appear to lack the genetic mutation that normally causes FSHD. (bioquicknews.com)
  • Classical views have attributed phenotypic variation to differences in primary DNA structure, be it through aberrant mutation or an inherited sequence allele. (wikipedia.org)
  • The P22 packaged DNA carries a direct duplication of about 4% at both ends since the inside of the virion has more space than is filled by 100% of the sequence. (wikipedia.org)
  • This process is called "headful packaging" since replicated DNA is "stuffed" into the virion until it is full, rather than filling each virion with a single copy of the sequence. (wikipedia.org)
  • Direct DNA damage can induce changes to the sequence variants. (wikipedia.org)
  • genomes
  • Epigenomic maintenance is a continuous process and plays an important role in stability of eukaryotic genomes by taking part in crucial biological mechanisms like DNA repair. (wikipedia.org)
  • translocation
  • The terminase-λDNA complex binds to the portal vertex of a prohead, and translocation of the DNA into the shell ensues. (genetics.org)
  • Translocation moves the DNA-packaging complex along the DNA until the next cos is encountered and the terminase docked at the portal vertex recognizes and cuts the downstream cos . (genetics.org)
  • Because cosQ mutants fail to cut the downstream cos and fail to stop translocation at cos , the shell is filled to capacity, and because the protruding DNA prevents tail attachment, the cosQ defect is lethal. (genetics.org)
  • chromosomal
  • L. Wilhelm, F. Bürmann, A. Minnen, H.-C. Shin, C.P. Toseland, B.-H. Oh, S. Gruber: SMC condensin entraps chromosomal DNA by an ATP hydrolysis dependent loading mechanism in Bacillus subtilis. (innovations-report.com)
  • strand
  • The depolarization model proposes that cosQ acts in presenting a gpA subunit to the bottom strand of cosN by forming a bend in the region of DNA between cosQ and cosN , forming a loop for cosQ and cosN to be aligned in the same orientation. (genetics.org)
  • DNA supercoiling refers to the over- or under-winding of a DNA strand, and is an expression of the strain on that strand. (wikipedia.org)
  • Experiments performed with ionizing radiation linked γ- phosphorylation of H2AX to DNA double-strand break. (wikipedia.org)
  • terminase
  • The ability to at least partially co-localise with the terminase complex appeared necessary for the ability of the mutants to support virus growth and DNA packaging, suggesting that this interaction may be essential for the function of UL32. (gla.ac.uk)
  • fibers
  • In order to ensure that the genetic material is equally and accurately distributed between the two daughter cells during cell division, the DNA fibers must remain in an orderly and closely-packed condition. (innovations-report.com)
  • In order to ensure the DNA's secure transport during cell division, the long and coiled DNA fibers must be tightly packed. (innovations-report.com)
  • It could for example stick together the different DNA fibers. (innovations-report.com)
  • enzymes
  • Many topoisomerase enzymes sense supercoiling and either generate or dissipate it as they change DNA topology. (wikipedia.org)
  • While DNA methylation is stable and heritable, it can be reversed by an antagonistic group of enzymes known as DNA de-methylases. (wikipedia.org)
  • genetic
  • Deoxyribonucleic acid (DNA) was shown to be the molecular repository of genetic information by experiments in the 1940s to 1950s. (wikipedia.org)
  • Sperm cells contribute approximately half of the nuclear genetic information to the diploid offspring (excluding, in most cases, mitochondrial DNA). (wikipedia.org)
  • viruses
  • to start questioning whether viruses are alive, revive the debate about the origin of DNA viruses and their possible role in the emergence of the eukaryotic nucleus. (wikipedia.org)
  • meiosis
  • DNA damages present in spermatozoa in the period after meiosis but before fertilization may be repaired in the fertilized egg, but if not repaired, can have serious deleterious effects on fertility and the developing embryo. (wikipedia.org)
  • apparatus
  • Thus, an upper limit has been established for the size of heterology that can be accommodated by the packaging apparatus The size of the connector portal could be the basis for this limit. (genetics.org)
  • Nucleus
  • In each human cell, about two meters of DNA must fit into a cell nucleus that has a diameter of only a few thousandths of a millimeter. (innovations-report.com)
  • helical
  • The simple figure eight is the simplest supercoil, and is the shape a circular DNA assumes to accommodate one too many or one too few helical twists. (wikipedia.org)
  • The twist is the number of helical turns in the DNA and the writhe is the number of times the double helix crosses over on itself (these are the supercoils). (wikipedia.org)