Hanks S K
Molecular Biology Laboratory, Salk Institute for Biological Studies, San Diego, California 92138.
Mol Endocrinol. 1989 Jan;3(1):110-6. doi: 10.1210/mend-3-1-110.
The complete amino acid sequence for a novel member of the protein kinase family was deduced from the nucleotide sequence of a cloned human cDNA. This putative protein kinase, given the preliminary designation "PSK-C3," is similar in primary structure to phosphorylase kinase catalytic subunit (PhK-gamma) isolated from rabbit skeletal muscle. The level of similarity does not appear sufficient, however, to suggest that PSK-C3 represents the human homolog of skeletal muscle PhK-gamma. Rather, it seems likely that PSK-C3 is a novel PhK-gamma isoform. From a cross-species Northern hybridization experiment using adult rat tissue RNA, a transcript homologous to PSK-C3 was found to be abundant in the testis but could not be detected in any of 12 other tissues tested, including skeletal muscle, liver, and ovary. Increasing levels of PSK-C3 mRNA in the testis correlate with postnatal testicular development, suggesting possible hormonal regulation of gene transcription. Energy released by glycogeneolysis in the testis may help fuel the process of spermatogenesis.
从克隆的人类cDNA的核苷酸序列推导得出了蛋白激酶家族一个新成员的完整氨基酸序列。这个假定的蛋白激酶，初步命名为“PSK-C3”，其一级结构与从兔骨骼肌分离出的磷酸化酶激酶催化亚基（PhK-γ）相似。然而，相似程度似乎不足以表明PSK-C3代表骨骼肌PhK-γ的人类同源物。相反，PSK-C3似乎很可能是一种新的PhK-γ同工型。通过使用成年大鼠组织RNA进行的跨物种Northern杂交实验，发现与PSK-C3同源的转录本在睾丸中大量存在，但在包括骨骼肌、肝脏和卵巢在内的其他12种测试组织中均未检测到。睾丸中PSK-C3 mRNA水平的升高与出生后睾丸的发育相关，提示基因转录可能受激素调节。睾丸中糖原分解释放的能量可能有助于为精子发生过程提供能量。
