A developmentally regulated chaperone complex for the endoplasmic reticulum of male haploid germ cells

van Lith, M.; Karala, A.; Bown, D.; Gatehouse, J.; Ruddock, L.; Saunders, P; Benham, AM.

Abstract

Glycoprotein folding is mediated by lectin-like chaperones and protein disulfide isomerases (PDIs) in the endoplasmic reticulum (ER). Calnexin and the PDI homologue ERp57 work together to help fold nascent polypeptides with glycans located toward the N-terminus of a protein, whereas PDI and BiP may engage proteins that lack glycans or have sugars toward the C-terminus. In this study, we show that the PDI homologue PDILT is expressed exclusively in post-meiotic male germ cells, in contrast to the ubiquitous expression of many other PDI family members in the testis. PDILT is induced during puberty and represents the first example of a PDI family member under developmental control. We find that PDILT is not active as an oxido-reductase, but interacts with the model peptide -somatostatin and nonnative BPTI in vitro, indicative of chaperone activity. In vivo, PDILT forms a tissue-specific chaperone complex with the calnexin homologue calmegin. The identification of a redox-inactive chaperone partnership defines a new system of testis-specific protein folding with implications for male fertility.

Citation

van Lith, M., Karala, A., Bown, D., Gatehouse, J., Ruddock, L., Saunders, P., & Benham, A. (2007). A developmentally regulated chaperone complex for the endoplasmic reticulum of male haploid germ cells. Molecular Biology of the Cell, 18(8), 2795-2804. https://doi.org/10.1091/mbc.e07-02-0147

• Journal Article Type: Article
• Publication Date: Aug 1, 2007
• Deposit Date: Oct 1, 2008
• Publicly Available Date: Oct 1, 2008
• Journal: Molecular biology of the cell
• Electronic ISSN: 1939-4586
• Publisher: American Society for Cell Biology
• Peer Reviewed: Peer Reviewed
• Volume: 18
• Issue: 8
• Pages: 2795-2804
• DOI: https://doi.org/10.1091/mbc.e07-02-0147
• Public URL: https://durham-repository.worktribe.com/output/1564865