HETEROGENEITY OF THE 59-KDA DYSTROPHIN-ASSOCIATED PROTEIN REVEALED BY CDNA CLONING AND EXPRESSION

作者：YANG B; IBRAGHIMOVBESKROVNAYA O; MOOMAW CR; SLAUGHTER CA; CAMPBELL KP

来源：JOURNAL OF BIOLOGICAL CHEMISTRY, 1994, 269(8): 6040-6044.

DOI：10.1016/s0021-9258(17)37566-x

The 59-kDa dystrophin-associated protein triplet (59-DAP) is a component of the dystrophin-glycoprotein complex which may directly associate with dystrophin. The cDNA encoding one component (59-1 DAP) of the 59-DAP triplet has now been cloned from rabbit skeletal muscle. The deduced amino acid sequence of 59-1 DAP predicts a 505-amino acid polypeptide containing nine potential phosphorylation sites and no predicted transmembrane domains. This is consistent with the 59-1 DAP being a peripheral membrane protein associated with the cytoplasmic face of the dystrophin-glycoprotein complex. Affinity-purified antibodies against rabbit 59-1 DAP fusion proteins only recognize the lowest band of the 59-DAP triplet in skeletal muscle sarcolemma and isolated dystrophin-glycopratein complex. The tissue-specific expression of 59-1 DAP mRNA, which is most prominent in skeletal and cardiac muscle and is also detected in brain, parallels that of dystrophin but not of utrophin. Levels of 59-1 DAP mRNA are unaffected in mdx mouse skeletal and cardiac muscles, although all dystrophin-associated proteins, including 59-DAP, are greatly reduced in mdx mouse skeletal muscle. However, in mdx mouse cardiac muscle, the up-regulation of utrophin preserves all dystrophin-associated proteins except 59-DAP. Our results suggest that the 59-DAP triplet may contain different protein species and that the 59-1 DAP may associate more specifically with dystrophin than with utrophin.

• 出版日期1994-2-25