| First Author | Li S | Year | 2000 |
| Journal | Biol Reprod | Volume | 63 |
| Issue | 6 | Pages | 1594-600 |
| PubMed ID | 11090425 | Mgi Jnum | J:65896 |
| Mgi Id | MGI:1927428 | Doi | 10.1095/biolreprod63.6.1594 |
| Citation | Li S, et al. (2000) A novel N-terminal domain directs membrane localization of mouse testis-specific calpastatin. Biol Reprod 63(6):1594-600 |
| abstractText | Multiple isoforms of calpastatin have been identified with unique N-terminal regions followed by identical calpain inhibitory domains (II-IV). In many instances the isoforms are cell-type specific, although the precise functional differences among these N-terminal regions are largely unknown. Here we report a germ cell-specific isoform of calpastatin (tCAST) that consists of a novel N-terminal peptide of 40 amino acids (domain T) followed by domains II to IV of somatic calpastatin (sCAST). Domain T is responsible for membrane association of tCAST through a protein modification by myristylation. Mutation of the myristylation site eliminates membrane targeting. Unlike most of the isoforms of calpastatin that are generated through alternative RNA splicing or post-translational proteolysis, the testis-specific isoform is transcribed from an intronic promoter in haploid germ cells of the testis. The intronic promoter directs specific expression of a reporter transgene in developing germ cells of the mouse testis. |
