Strahler J R, Zhu X X, Hora N, Wang Y K, Andrews P C, Roseman N A, Neel J V, Turka L, Hanash S M
Department of Pediatrics, University of Michigan School of Medicine, Ann Arbor 48109-0510.
Proc Natl Acad Sci U S A. 1993 Jun 1;90(11):4991-5. doi: 10.1073/pnas.90.11.4991.
We have developed a database of lymphoid polypeptides detected by two-dimensional polyacrylamide gel electrophoresis to aid in studies of leukemogenesis and of mutation affecting protein structure. In prior studies, we observed a 19-kDa phosphopolypeptide which was induced with proliferation in mature T cells and constitutively expressed in immature thymocytes. In this report we describe the identification of this polypeptide as the phosphorylated form of dUTPase (EC 3.6.1.23), following cDNA cloning of the gene, based on a partial amino acid sequence of the phosphopolypeptide. Studies of the expression and phosphorylation of dUTPase in human T cells indicate that accumulation and phosphorylation of dUTPase in mature T cells occur in a cell cycle-dependent manner. Interestingly, noncycling immature thymocytes express constitutively high levels of phosphorylated and unphosphorylated dUTPase. These results suggest an important role for dUTPase in immature thymocytes that is independent of proliferation.
我们开发了一个通过二维聚丙烯酰胺凝胶电泳检测到的淋巴样多肽数据库，以辅助白血病发生及影响蛋白质结构的突变研究。在之前的研究中，我们观察到一种19 kDa的磷酸化多肽，它在成熟T细胞增殖时被诱导表达，并在未成熟胸腺细胞中组成性表达。在本报告中，我们基于该磷酸化多肽的部分氨基酸序列，通过基因的cDNA克隆，将此多肽鉴定为dUTPase（EC 3.6.1.23）的磷酸化形式。对人T细胞中dUTPase表达和磷酸化的研究表明，成熟T细胞中dUTPase的积累和磷酸化以细胞周期依赖性方式发生。有趣的是，非循环的未成熟胸腺细胞组成性地表达高水平的磷酸化和未磷酸化dUTPase。这些结果表明dUTPase在未成熟胸腺细胞中具有独立于增殖的重要作用。
