Molecular cloning of the cDNA for androgen-dependent sperm-coating glycoproteins secreted by the rat epididymis.


Journal Article

cDNA clones coding for two closely related androgen-dependent sperm-coating glycoproteins secreted by the rat epididymis were selected by screening an epididymal cDNA library constructed in lambda gt 11 with affinity-purified antibody directed against the glycoproteins. The largest clone of 956 nucleotides provided coding information for a protein of 246 amino acids of which the first 19 residues comprise a putative signal peptide sequence which when cleaved would produce a mature protein of 227 residues and a molecular mass of 26 kDa. Confirmation of the identity of the clone was provided by a match between the amino acid sequence predicted from the cDNA sequence and the actual amino acid sequence determined for a tryptic peptide fragment of one of the pure glycoproteins. It is probable that the primary amino acid sequence of the two glycoproteins is identical. Northern blot and slot-blot analysis revealed that the mRNA for the glycoproteins is approximately 1250 nucleotides long and that the concentration of the mRNA in the epididymis is androgen-dependent. The glycoproteins and their mRNAs were unique to the epididymis as determined by Western and Northern blots, respectively, since signals were absent from skin, brain, liver, kidney, heart, skeletal muscle and testis. Cross-reacting proteins of slightly smaller apparent molecular mass were detected in extracts of mouse and guinea-pig epididymis, but not rabbit or bull epididymis. Comparison with existing protein data bases revealed that the epididymal glycoproteins display significant sequence homology with yeast carboxypeptidase Y.

Full Text

Duke Authors

Cited Authors

  • Brooks, DE; Means, AR; Wright, EJ; Singh, SP; Tiver, KK

Published Date

  • November 17, 1986

Published In

Volume / Issue

  • 161 / 1

Start / End Page

  • 13 - 18

PubMed ID

  • 3780731

Pubmed Central ID

  • 3780731

International Standard Serial Number (ISSN)

  • 0014-2956

Digital Object Identifier (DOI)

  • 10.1111/j.1432-1033.1986.tb10118.x


  • eng

Conference Location

  • England