Although the ultimate targets of many signal transduction pathways are nuclear transcription factors, the vast majority of known protein kinases are cytosolic. Here, we report on a novel human kinase that is present exclusively in the nucleus. Kinase activity is increased upon cellular proliferation and is markedly elevated in patients with acute and chronic lymphocytic leukemias. We have identified a human gene that encodes this nuclear kinase and find that it is closely related to Drosophila female sterile homeotic (fsh), a developmental regulator with no known biochemical activity. Collectively, these results suggest that this nuclear kinase is a component of a signal transduction pathway that plays a role in Drosophila development and human growth control.

中文翻译：

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一种新型的，促分裂原活化的核激酶与果蝇发育调节剂有关。

尽管许多信号转导途径的最终靶标是核转录因子，但绝大多数已知的蛋白激酶是胞质的。在这里，我们报道了一种仅存在于细胞核中的新型人类激酶。激酶活性随细胞增殖而增加，并在患有急性和慢性淋巴细胞性白血病的患者中明显升高。我们已经鉴定出一种编码该核激酶的人类基因，并发现它与果蝇雌性不育同种异体动物（fsh）（一种未知的生化活性的发育调节剂）密切相关。总的来说，这些结果表明该核激酶是信号转导通路的一个组成部分，在果蝇的发育和人类生长的控制中发挥作用。