The Gas1 glycoprotein, a putative wall polymer cross-linker

Biochim Biophys Acta. 1999 Jan 6;1426(2):385-400. doi: 10.1016/s0304-4165(98)00138-x.

Abstract

The yeast cell wall, which for years has been regarded as a static cellular component, has been revealed to be dynamic in its structure and composition and complex in its enzymatic activity. The S. cerevisiae cell wall is composed of beta-1,3/beta-1,6-glucans, mannoproteins, and chitin, which are assembled into an extracellular matrix essential for maintenance of cell integrity. Gas1p, a glycoprotein anchored to the outer leaflet of the plasma membrane through a glycosylphosphatidylinositol, plays a key role in cell wall assembly. Loss of Gas1p leads to several morphogenetic defects and to a decrease in the amount of cross-links between the cell wall glucans. These defects in turn trigger a compensatory response that guarantees cell viability. Several Gas1p homologs have been isolated from Candida species and S. pombe. The Gas1p family also includes two plant proteins with endo-beta-1,3-glucanase activity. Sequence comparisons reveal that Gas1p family proteins have a modular organization of domains. The genetic and molecular analyses reviewed here suggest that Gas1p could play a role as a polymer cross-linker, presumably by catalyzing a transglycosylation reaction.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Cell Survival
  • Cell Wall / chemistry
  • Cell Wall / metabolism*
  • Chitin / metabolism
  • Gene Expression Regulation
  • Glycosylphosphatidylinositols / chemistry
  • Membrane Glycoproteins / biosynthesis*
  • Membrane Glycoproteins / chemistry
  • Membrane Glycoproteins / genetics
  • Molecular Sequence Data
  • Polymers / chemistry
  • Saccharomyces cerevisiae / chemistry
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins*
  • Sequence Alignment

Substances

  • GAS1 protein, S cerevisiae
  • Glycosylphosphatidylinositols
  • Membrane Glycoproteins
  • Polymers
  • Saccharomyces cerevisiae Proteins
  • Chitin