ROLE OF THE P34CDC2 RELATED PITSLRE PROTEIN KINASES

描述(改编自调查人员的摘要)：反复发生的变更 代表了结构染色体最常见的部位 所有人类实体肿瘤的异常，包括人类皮肤 恶性黑素瘤。在黑色素瘤中，涉及1号染色体的断裂点通常 在1点36点累积。编码PITSLRE蛋白激酶的两个基因--CDc2L1 和Cdc2L2，定位于染色体带区1p36。PITSLRE蛋白 激酶是p34cdc2超基因家族的一部分。有几条证据 提示一些PITSLRE蛋白激酶亚型参与了 细胞凋亡信号转导。我们已经证实了CDc2L等位基因的缺失 死于黑色素瘤。我们还可以证明PITSLRE的p110亚型被 半胱氨酸天冬氨酸酶转化为更小的p46亚型。P46亚型保留了激酶活性，但 似乎改变了它的底物专一性。还有一个不同之处在于 黑色素瘤细胞(带有野生型和突变型CDc2L等位基因)对 细胞凋亡性刺激。因此，要检验的主要假设是 Caspase处理的PITSLRE亚型作为下游效应子在 细胞凋亡信号通路与PITSLRE蛋白激酶的破坏 功能通过去调节在黑色素瘤的发展中起功能作用 控制细胞死亡。三个具体目标是：(1)研究 CDc2L基因(PITSLRE)在黑色素瘤进展过程中的变化 聚合酶链式反应-单链构象多态性和DNA直接测序。中国散发性黑色素瘤病例档案 分析了黑色素瘤的不同组织学阶段的特定突变。 CDC2L1基因内的区域。此外，家族性黑色素瘤家族有关联 此外，还研究了CDC2L1基因突变。(2)隔离和 Caspase处理的PITSLRE异构体底物的表征 酵母双杂交方法学和(3)阐明其生物学功能 通过产生cdc2L1缺陷小鼠使cdc2L基因失活。增加了 对导致这种疾病的关键基因改变的理解 黑色素瘤的发生和发展可能导致遗传标记 黑色素瘤。可以使用定义CDC2L1改变的重要性来识别 有趣的亚群。CDc2L1基因的改变也可能对预后有预测作用 当与临床数据一起考虑时，它的价值。最后，增加了 对Cdc2L生物学作用的理解可能会带来新的和创新的 治疗黑色素瘤的策略。

Description (Adapted from the investigator's abstract): Recurring alterations of chromosome 1 represent the most frequent site of structural chromosome abnormalities across all human solid tumors, including human cutaneous malignant melanoma. In melanoma, breakpoints involving chromosome 1 often accumulate at 1p36. The two genes encoding the PITSLRE protein kinases, Cdc2L1 and Cdc2L2, are localized to chromosome band region 1p36. The PITSLRE protein kinases are part of the p34cdc2 supergene family. Several lines of evidence suggests that some of the PITSLRE protein kinases isoforms are involved in apoptotic signal transduction. We have demonstrated deletion of Cdc2L alleles in melanoma. We can also show that the p110 isoform of PITSLRE is cleaved by caspases to a smaller p46 isoform. The p46 isoform retains kinase activity but appears to change its substrate specificity. There is also a difference in the sensitivity of melanoma cells (with wildtype and mutant Cdc2L alleles) to apoptotic stimuli. Thus, the principal hypothesis to be tested is that the caspase-processed PITSLRE isoform functions as a downstream effector in apoptotic signaling pathways and that disruption of PITSLRE protein kinase function plays a functional role in melanoma development by deregulating controlled cell death. The three specific aims are: (1) To study the timing of Cdc2L gene (PITSLRE) alteration during melanoma tumor progression using PCR-SSCP and direct DNA sequencing. Archival sporadic melanoma cases from various histological stages of melanoma are analyzed for mutations of specific regions within the Cdc2L1 gene. In addition familial melanoma kindreds linked to 1p are also investigated for Cdc2L1 gene alterations. (2) To isolate and characterize the substrate for the caspase processed PITSLRE isoform using yeast two hybrid methodology and (3) To elucidate the biological function of Cdc2L gene inactivation by generating Cdc2L1 deficient mice. An increased understanding of the critical gene alterations that give rise to the development and progression of melanoma may lead to genetic markers for melanoma. Defining the importance of Cdc2L1 alterations may be used to identify interesting subpopulations. Genetic changes of Cdc2L1 also may have prognostic value when considered in tandem with clinical data. Finally, increased understanding of biological role of Cdc2L may lead to new and innovative strategies to treat melanoma.