Disease relevance of CNE1

• The calnexin homologue (Cne1p) of Saccharomyces cerevisiae was expressed in Escherichia coli to evaluate its chaperone function [1].

High impact information on CNE1

• Unlike the sequence-related Saccharomyces cerevisiae CNE1 gene, the S.pombe cnx1+ gene was essential for cell viability [2].
• These results suggest that the interface between Mpd1p and Cne1p is near the peptide-binding site of Cne1p [3].
• Saccharomyces cerevisiae CNE1 encodes an endoplasmic reticulum (ER) membrane protein with sequence similarity to calnexin and calreticulin and functions as a constituent of the ER quality control apparatus [4].
• The protein predicted from the CNE1 DNA sequence shares some of the motifs with calnexin and calreticulin, and it is 24% identical and 31% similar at the amino acid level with mammalian calnexin [4].
• On the basis of its solubility in detergents and its lack of extraction from membranes by 2.5 M urea, high salt, and sodium carbonate at pH 11.5, we have established that Cne1p is an integral membrane protein [4].

Biological context of CNE1

• We also observe a approximately 30% decrease in beta-1,6-glucan upon disruption of the CNE1 gene, a phenotype that is additive with other beta-1,6-glucan synthetic mutants [5].

Anatomical context of CNE1

• The P-domain deletion mutant and the letcin site mutants partially decreased the ability to suppress the aggregation of citrate synthase (CS) and chicken egg yolk immunoglobulin at levels different from Cne1p [6].

Other interactions of CNE1

• To explore the involvement of other N-chain-dependent events with beta-1,6-glucan synthesis, we investigated the Saccharomyces cerevisiae KRE5 and CNE1 genes, which encode homologs of the "quality control" components UDP-Glc:glycoprotein glucosyltransferase and calnexin, respectively [5].
• Finally, we present evidence that ER-to-cytosol toxin export is mediated by the Sec61p translocon and requires functional copies of the lumenal ER chaperones Kar2p and Cne1p [7].

Analytical, diagnostic and therapeutic context of CNE1

• We have used a polymerase chain reaction strategy to identify in the yeast Saccharomyces cerevisiae genes of the mammalian calnexin/calreticulin family, and we have identified and isolated a single gene, CNE1 [4].
• Localization of the Cne1p protein by differential and analytical subcellular fractionation as well as by confocal immunofluorescence microscopy showed that it was exclusively located in the endoplasmic reticulum (ER), despite the lack of known ER retention motifs [4].

References