Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • CpG distribution and suppression  (1)
  • Gene mutations  (1)
  • serine proteinase  (1)
  • 1
    Electronic Resource
    Electronic Resource
    The distribution of the dinucleotide CpG and cytosine methylation in the vitellogenin gene family (1987)
    Springer
    Journal of molecular evolution 25 (1987), S. 107-115 
    Details
    ISSN: 1432-1432
    Keywords: CpG distribution and suppression ; Vitellogenin genes ; DNA methylation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sequence data from regions of five vertebrate vitellogenin genes were used to examine the frequency, distribution, and mutability of the dinucleotide CpG, the preferred modification site for eukaryotic DNA methyltransferases. The observed level of the CpG dinucleotide in all five genes was markedly lower than that expected from the known mononucleotide frequencies. CpG suppression was greater in introns than in exons. CpG-containing codons were found to be avoided in the vitellogenin genes, but not completely despite the redundancy of the genetic code. Frequency and distribution patterns of this dinucleotide varied dramatically among these otherwise closely related genes. Dense clusters of CpG dinucleotides tended to appear in regions of either functional or structural interest (e.g., in the transposon-like Vi-element ofXenopus) and these clusters contained 5-methylcytosine (5 mC). 5 mC is known to undergo deamination to form thymidine, but the extent to which this transition occurs in the heavily methylated genomes of vertebrates and its contribution to CpG suppression are still unclear. Sequence comparison of the methylated vitellogenin gene regions identified C→T and G→A substitutions that were found to occur at relatively high frequencies. The predicted products of CpG deamination, TpG and CpA, were elevated. These findings are consistent with the view that CpG distribution and methylation are interdependent and that deamination of 5 mC plays an important role in promoting evolutionary change at the nucleotide sequence level.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02101752
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Disease-causing mutations in the human genome (2000)
    Springer
    European journal of pediatrics 159 (2000), S. S173 
    Details
    ISSN: 1432-1076
    Keywords: Key words Databases ; Deletions ; Gene mutations ; Insertions ; Substitutions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A considerable number of gene mutations has now been reported in a total of more than 1000 different human genes. Data on these mutations and their associated phenotypes have been collated and are available online through two major databases: Online Mendelian Inheritance in Man in Baltimore and the Human Gene Mutation Database in Cardiff. Since the non-randomness of mutation is determined largely by the local DNA sequence environment, the study of mutation may not only yield information on underlying mechanisms but also lead to the optimization of mutation search strategies. Conclusion There is a high frequency of CG to TG or CA mutations in the human genome due to deamination of 5′methyl-cytosine. The second most common type of mutations in human disorders is short deletions or insertions of less than 20 nucleotides.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00014395
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Prothrombin cleavage by human vascular smooth muscle cells: A potential alternative pathway to the coagulation cascade (1995)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 59 (1995), S. 514-528 
    Details
    ISSN: 0730-2312
    Keywords: prothrombin ; prethrombin 2 ; fragment 1.2 ; α-thrombin ; prothrombin activation ; serine proteinase ; human vascular smooth muscle cells ; mitogenic activity ; enzymatic activity ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Thrombin is a potent mitogen for human vascular smooth muscle cells (HVSMC) and its enzymatic activity is required for this function. The present study demonstrates that prothrombin is also mitogenic for HVSMC due to the generation of enzymatically active thrombin which occurs upon incubation of prothrombin with the cells. Analysis by SDS-PAGE, immunoblotting, and amino acid sequencing revealed that prothrombin incubated with HVSMC undergoes limited proteolysis. Prethrombin 1 was formed through cleavage at R155-S156. Cleavage at R271-T272 generated fragment 1.2 and prethrombin 2 whilst cleavage at R284-T285 yielded truncated prothrombin 2 (prethrombin 2′). However, cleavage at R320-I321 which, during prothrombin activation produces two-chain α-thrombin, was not detectable. Studies on HVSMC-conditioned medium revealed that a similar pattern of prothrombin cleavage occurred by a cell-secreted factor(s). Amidolytic activity analysis indicated that 1-3% catalytically active thrombin-like activity was generated upon incubation of prothrombin with HVSMC-conditioned medium. By treating conditioned medium with various classes of proteinase inhibitors or hirudin, it was determined that prothrombin is cleaved by a cell-derived serine proteinase-like factor(s) at R271-S272 and by α-thrombin at R155-S156 and R284-T285. Antibodies neutralising the activity of either urokinase, tissue plasminogen activator, or factor Xa failed to alter the prothrombin cleaving activity of conditioned medium. This activity which may catalyse an alternative pathway for the generation of thrombin, was eluted from a gel filtration column as a single peak with apparent molecular mass of 30-40 kDa. © 1995 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240590411
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...