Premium
Low external pH induces HOG1‐dependent changes in the organization of the Saccharomyces cerevisiae cell wall
Author(s) -
Kapteyn J. C.,
Ter Riet B.,
Vink E.,
Blad S.,
De Nobel H.,
Van Den Ende H.,
Klis F. M.
Publication year - 2001
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1046/j.1365-2958.2001.02242.x
Subject(s) - cell wall , saccharomyces cerevisiae , biology , glucan , biochemistry , yeast , cell , osmotic concentration , gene , microbiology and biotechnology
Low environmental pH strongly affected the organization of the Saccharomyces cerevisiae cell wall, resulting in rapidly induced resistance to β1,3‐glucanase. At a molecular level, we found that a considerable amount of Cwp1p became anchored through a novel type of linkage for glycosylphosphatidylinositol (GPI)‐dependent cell wall proteins, namely an alkali‐labile linkage to β1,3‐glucan. This novel type of modification for Cwp1p did not require the presence of a GPI‐derived structure connecting the protein with β1,6‐glucan. In addition, we found high levels of Cwp1p, which was double‐anchored through both the novel alkali‐sensitive bond to β1,3‐glucan and the alkali‐resistant GPI‐derived linkage to β1,6‐glucan. Further cell wall analyses demonstrated that Pir2p/Hsp150 and possibly other Pir cell wall proteins, which were already known to be linked to the β1,3‐glucan framework by an alkali‐sensitive linkage, were also more efficiently retained in the cell wall at pH 3.5 than at pH 5.5. Consequently, the alkali‐sensitive type of linkage of cell wall proteins to β1,3‐glucan was induced by low pH. The low pH‐induced alterations in yeast cell wall architecture were demonstrated to be dependent on a functional HOG1 gene, but not on the Slt2p‐mediated MAP kinase pathway. Consistent with this observation, DNA microarray studies revealed transcriptional induction of many known high‐osmolarity glycerol (HOG) pathway‐dependent genes, including four cell wall‐related genes, namely CWP1 , HOR7 , SPI1 and YGP1 .