GPI7 affects cell-wall protein anchorage in Saccharomyces cerevisiae and Candida albicans.
Glycosylphosphatidylinositol (GPI)-anchoring represents a mechanism for attaching proteins to the cell surface of all eukaryotic cells. Two localizations of GPI proteins have been observed in the yeasts Saccharomyces cerevisiae and Candida albicans: plasma membrane and cell wall. The signals and the mechanisms involved in this differential targeting are presently not well understood. Here several cell-wall-related phenotypes of a gpi7/las21 deletion are described, where GPI7/LAS21 encodes a GPI-anchor-modifying activity. In both organisms, the structure and composition of the cell wall was modified, with a clear increase in chitin deposition. Cell-wall-targeted proteins accumulated in the growth medium, whereas the protein content of the cell wall decreased significantly, suggesting inefficiency of the covalent linkage. The level of plasma-membrane-targeted GPI proteins was not affected. Sequence analyses revealed that gene families involved in the addition of phosphoethanolamines to the core GPI anchor are highly conserved between eukaryotes, with the exception of the Gpi7 family which seems to be fungus-specific. These data are compatible with the notion that the phosphoethanolamine added by Gpi7 protein to the GPI anchor is a key factor in the covalent linkage of cell-wall proteins to fungal cell-wall components.
Richard
Mathias
M
Laboratoire de Génétique Moléculaire et Cellulaire, Institut National Agronomique Paris-Grignon, UMR-INRA216, URA-CNRS1925, BP01, 78850 Thiverval-Grignon, France1.
de Groot
Piet
P
Fungal Research Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands2.
Courtin
Olivier
O
Aventis Pharma, 102 route de Noisy, 93235 Romainville cedex, France3.
Poulain
Daniel
D
Laboratoire de Mycologie Fondamentale et Appliquée, INSERM EPI 9915, Université de Lille II, Faculté de Médecine H. Warembourg, Pôle Recherche, Place Verdun, 59037 Lille Cedex, France4.
Klis
Frans
F
Fungal Research Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands2.
Gaillardin
Claude
C
Laboratoire de Génétique Moléculaire et Cellulaire, Institut National Agronomique Paris-Grignon, UMR-INRA216, URA-CNRS1925, BP01, 78850 Thiverval-Grignon, France1.
D000595:Amino Acid Sequence; D002176:Candida albicans / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism*; D003470:Culture Media; D004983:Ethanolamines / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism*; D017353:Gene Deletion; D008565:Membrane Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
D003470:Culture Media; D004983:Ethanolamines; D005656:Fungal Proteins; C118052:MCD4 protein, S cerevisiae; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; C005448:phosphorylethanolamine; C413542:GPI13 protein, S cerevisiae; C119814:LAS21 protein, S cerevisiae; D017853:Phosphotransferases (Alcohol Group Acceptor)