High impact information on CSH1

• In this study, we found that Csg1 and Csh1 are N-glycosylated with core-type and mannan-type structures, respectively [1].
• Regulation of the Transport and Protein Levels of the Inositol Phosphorylceramide Mannosyltransferases Csg1 and Csh1 by the Ca2+-binding Protein Csg2 [1].
• However, uncomplexed Csh1 cannot exit from the endoplasmic reticulum [1].
• Thus, Csg2 has several regulatory functions for Csg1 and Csh1, including stability, transport, and gene expression [1].
• Here we show that open reading frame YBR161w, renamed CSH1, is functionally homologous to CSG1 and that deletion of both genes abolishes MIPC and M(IP)2C synthesis without affecting protein mannosylation [2].

Biological context of CSH1

• Loss of Csg1p and Csh1p has no effect on clathrin- or AP-3 adaptor-mediated protein transport from the Golgi to the vacuole [2].
• Analyses using Deltacsg1 and Deltacsh1 cells in the Deltaipt1, Deltasur2, or Deltascs7 genetic background demonstrated that Csh1p has a different substrate specificity from Csg1p [3].

Anatomical context of CSH1

• Further identification of the glycosylated residues suggests that both Csg1 and Csh1 exhibit membrane topology with their C termini in the cytosol and their mannosyltransferase domains in the lumen [1].

Associations of CSH1 with chemical compounds

• To better understand the molecular basis of the Ca(2+)-induced growth defect in IPC-C-overaccumulating cells, we searched for genes whose overexpression restored Ca(2+) tolerance in a mutant lacking the IPC mannosyltransferases Csg1p and Csh1p [4].

Other interactions of CSH1

• The sequence of a 5653 bp DNA fragment of the right arm of chromosome II of Saccharomyces cerevisiae contains two unknown open reading frames (YBR1212 and YBR1213) next to gene CDC28 [5].
• After complexing with Csg2, both Csg1 and Csh1 function in the Golgi, and then are delivered to the vacuole for degradation [1].

References