REGULATION OF THE MAPK ERK3

描述：（申请人的描述） 蛋白激酶在正常细胞中占有重要地位， 增殖、分化和癌症。 细胞外信号 调节激酶家族（erks）最近被证明在 调节有丝分裂的细胞外信号的传递， 分化，以及细胞对环境应激的反应， 热、紫外线和渗透胁迫。 Erk-1和erk-2主要 服务于促有丝分裂和分化信号，而Jun N- 末端激酶（JNK）和p38 MAPK参与介导 细胞对压力的反应 临床上，JNK和p38 MAPK正在出现 作为细胞对感染性休克、发热和 辐射 申请人建议研究erk-3，erk的一个成员 在激酶中与erk-1和erk-2具有超过50%同源性的家族 催化域 最近的报告表明，erk-3可能是针对在 某些类型的癌症，包括急性非淋巴细胞白血病和 结肠癌 本申请的目的是剖析 erk-3 MAPK 本申请人提出首先识别生理学上的 促进ERK-3活化的条件 ERK-3 她将通过确定激活条件来实现这一点 激酶以纯化酶的活性形式。 活性 酶的制备将用于评估磷酸化是否是 这种蛋白质的活性所必需的。 如果这被证明是 她将使用生物化学和分子生物学的综合策略， 试图纯化激活ERK-3的激酶。 如果监管机构 如果erk-3的活性被证明是 与磷酸化状态无关，她将使用双杂交筛选 以鉴定潜在的ERK-3调节剂。 第二，她建议确定 并表征erk-3 MAPK内的调节结构域。 第三，她有 证明在体外，erk-3磷酸化转录因子， C-Jun和ATF-2 她建议调查这一影响， 磷酸化对DNA结合和体内和体外转录的影响。

DESCRIPTION: (Applicant's Description) Protein kinases occupy an important position in normal cellular proliferation, differentiation, and cancer. The extracellular signal regulated kinase family (erks) have recently been shown to be critical in the transmission of extracellular signals regulating mitogenesis, differentiation, and the cellular response to environmental stresses such as heat, ultraviolet light, and osmotic stress. Erk-1 and erk-2 principally serve to transduce mitogenic and differentiation signals, while Jun N- terminal kinase (JNK) and the p38 MAPK are involved in mediating the cellular response to stress. Clinically, JNK and the p38 MAPK are emerging as important molecules in the cellular response to septic shock, fever, and radiation. The applicant proposes to study erk-3, a member of the erk family bearing over 50 percent homology to erk-l and erk-2 in the kinase catalytic domain. Recent reports suggest that erk-3 may be targeted in certain types of cancers, including acute non-lymphoblastic leukemias and in colon cancer. It is the goal of this application to dissect the function and regulation of the erk-3 MAPK. The applicant proposes to first identify the physiological conditions that promote erk-3 activation in order to identify an activator of erk-3. She will do this by identifying activating conditions for this kinase in order to purify an active form of the enzyme. The active preparation of enzyme will be used to evaluate whether phosphorylation is required for the activity of this protein. Should this prove to be the case, she will use a combined strategy of biochemistry and molecular biology to attempt to purify the kinase(s) that activate erk-3. If the regulator is novel, she will clone it. If the activity of erk-3 is shown to be independent of its phosphorylation state, she will use a two hybrid screen to identify potential erk-3 regulators. Second, she proposes to identify and characterize regulatory domains within the erk-3 MAPK. Third, she has demonstrated that in vitro, erk-3 phosphorylates the transcription factors c-Jun and ATF-2. She proposes to investigate the effect of that phosphorylation on DNA-binding and transcription in vivo and in vitro.