These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Analysis of fibrinogen variants at gamma387Ile shows that the side chain of gamma387 and the tertiary structure of the gammaC-terminal tail are important not only for assembly and secretion of fibrinogen but also for lateral aggregation of protofibrils and XIIIa-catalyzed gamma-gamma dimer formation. Author: Kani S, Terasawa F, Yamauchi K, Tozuka M, Okumura N. Journal: Blood; 2006 Sep 15; 108(6):1887-94. PubMed ID: 16705085. Abstract: To examine the role of fibrinogen gamma-chain residue 387Ile in the assembly and secretion of this multichain protein, we synthesized a series of variants with substitution at gamma387 by Arg, Leu, Met, Ala, or Asp. Only the variant gamma387Asp showed impaired synthesis in the cells and very low secretion into the medium. In addition, we performed thrombin-catalyzed fibrin polymerization and factor (F) XIIIa-catalyzed cross-linking of the gamma-chain for 4 variants. The degree of lateral aggregation of protofibrils into fibrin fibers was slightly reduced for gamma387Arg and Ala, and moderately reduced for gamma387Leu and Met. Although the FXIIIa-catalyzed cross-linking for all of the variants was slower than that for gamma387Ile, that of gamma387Arg was much more markedly impaired than that of the others. In summary, our studies demonstrated that the specific residue at gamma387 or the conformation of gamma388-411 residues, but not the length of the gammaC tail, is critical for fibrinogen assembly and subsequent secretion. Moreover, this residue or the conformation is also important for not only the lateral aggregation of fibrin polymers but also the FXIIIa-catalyzed cross-linking of the gamma-chain. Interestingly, our results clearly indicate that the conformations critical for these 2 functions are different from each other.[Abstract] [Full Text] [Related] [New Search]