A Developmentally Regulated Chaperone Complex for the Endoplasmic Reticulum of Male Haploid Germ Cells
- 1 August 2007
- journal article
- Published by American Society for Cell Biology (ASCB) in Molecular Biology of the Cell
- Vol. 18 (8), 2795-2804
- https://doi.org/10.1091/mbc.e07-02-0147
Abstract
Glycoprotein folding is mediated by lectin-like chaperones and protein disulfide isomerases (PDIs) in the endoplasmic reticulum. 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 postmeiotic 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 Δ-somatostatin and nonnative bovine pancreatic trypsin inhibitor 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.Keywords
This publication has 55 references indexed in Scilit:
- ERp57 is essential for efficient folding of glycoproteins sharing common structural domainsThe EMBO Journal, 2006
- Insights into Deglutathionylation ReactionsPublished by Elsevier BV ,2006
- Protein disulfide isomerase–like proteins play opposing roles during retrotranslocationThe Journal of cell biology, 2006
- Three Binding Sites in Protein-disulfide Isomerase Cooperate in Collagen Prolyl 4-Hydroxylase Tetramer AssemblyPublished by Elsevier BV ,2005
- Teratozoospermia in mice lacking the transition protein 2 (Tnp2)Molecular Human Reproduction, 2001
- Discrimination between Native and Non-native Disulfides by Protein-disulfide IsomerasePublished by Elsevier BV ,2001
- Characterization and Chromosomal Localization of a New Protein Disulfide Isomerase, PDIp, Highly Expressed in Human PancreasDNA and Cell Biology, 1996
- HLA-DR associates with specific stress proteins and is retained in the endoplasmic reticulum in invariant chain negative cells.The Journal of Experimental Medicine, 1992
- Regulation of 'haploid expressed genes' in male germ cellsReproduction, 1990
- Endocytic Activities of Sertoli Cells in the RatAnnals of the New York Academy of Sciences, 1987