p120-catenin sub-family functions

描述(申请人提供)：连接素蛋白有助于所有动物细胞和组织的生物学，在不同的亚细胞中显示基本的胚胎和成体功能。例如，除了结合钙粘附素跨膜细胞-细胞黏附分子的内部(细胞质)结构域外，β-连环蛋白在Wnt发育信号中发挥着重要作用，在细胞核内它调节特定基因靶标的转录。这些基因靶点不仅对正常胚胎发育很重要，而且对包括结肠癌和黑色素瘤在内的人类疾病的发展也很重要。在这一更新应用中，我们集中在连环蛋白家族中知之甚少的成员的作用，特别是p120-连环蛋白亚家族的成员(p120-连环蛋白；ARVCF-连环蛋白；增量-连环蛋白)。一个主要的兴趣是上游Wnt通路信号如何产生p120亚家族反应的网络，以及那些更为人所知的β-连环蛋白反应。我们的目标包括阐明Wnt信号作用于p120亚家族成员的生化机制。为p120-catenin本身收集的证据表明，这种调节涉及到激酶活性和p120-catenin蛋白稳定性的调节。与ARVCF和Delta-catenin相关的初步证据也同样保留了Wnt途径反应性的可能性，例如，鉴定了两个涉及已知Wnt途径成分的新的Delta-catenin蛋白复合体。总之，我们的工作旨在扩大我们对连环蛋白生物学的理解范围，特别是关于p120-subF蛋白在Wnt信号转导中的新作用。在我们的研究中，我们将主要使用非洲爪哇(青蛙)胚胎。这种脊椎动物系统提供了方便的外源结构/试剂的引入(微量注射)、快速的外部发展以及许多生物化学和分子优势。对于功能分析，我们将结合发育表型的研究和蛋白质复合体形成或靶基因活性的生物化学和分子测试，利用敲除(吗啉寡核苷酸)、外源表达和挽救方法。为了补充我们在开发两栖动物胚胎方面的工作，我们将使用精选的哺乳动物细胞系，例如对Wnt有反应的HEK293T细胞。项目简介：Wnt信号通路对所有动物的发育都是必需的，而它后来的适当调节对维持健康仍然很重要。例如，90%的人类结肠癌和黑色素瘤的进展涉及Wnt通路的病理性激活。我们的建议研究了一组属于p120-catenin亚家族的蛋白质的功能，我们有证据和假设参与Wnt信号，他们的研究将有助于理解正常发育和人类疾病。

DESCRIPTION (provided by applicant): The catenin proteins contribute to the biology of all animal cells and tissues, displaying essential embryonic and adult functions within differing sub-cellular compartments. For example, in addition to binding the inner (cytoplasmic) domain of cadherin trans-membrane cell-cell adhesion molecules, beta-catenin is well known to play an essential role in Wnt developmental signaling where within the nucleus it regulates transcription from specific gene targets. These gene targets are not only important for normal embryogenesis but also for the progression of human diseases including colon carcinoma and melanoma. In this renewal application, we focus upon the roles of less understood members of the catenin family of proteins, specifically members of the p120-catenin sub-family (p120- catenin; ARVCF-catenin; delta-catenin). A major interest is how upstream Wnt- pathway signals produce a network of p120 sub-family responses in addition to those better known for beta-catenin. Our aims include elucidating the biochemical mechanisms by which Wnt signals act upon p120 sub-family members. Evidence gathered for p120-catenin itself suggests that such regulation involves kinase activity and modulation of p120-catenin protein stability. Preliminary evidence relating to ARVCF and delta-catenin likewise leaves open the possibility of Wnt-pathway responsiveness, with for example, identification of two novel delta-catenin protein complexes involving known Wnt- pathway components. Overall, our work is aimed at expanding the scope of our understanding of catenin biology, with particular regard to the novel roles of p120-subF proteins in Wnt signaling. For our studies, we will predominantly employ Xenopus laevis (frog) embryos. This vertebrate system offers facile introduction (micro-injection) of exogenous constructs/ reagents, rapid external development and many biochemical and molecular advantages. For functional analysis, we will utilize knock-down (morpholino oligonucleotide), exogenous expression and rescue approaches in conjunction with the study of developmental phenotypes and biochemical and molecular tests of protein complex formation or target gene activity. To complement our work in developing amphibian embryos, we will employ select mammalian cell lines, for example, Wnt-responsive HEK293T cells. Project narrative: The Wnt signaling pathway is required for the development of all animals, while it's proper later regulation remains important in maintaining health. For example, the progression of >90% of human colon carcinomas and melanomas involves pathological activation of the Wnt pathway. Our proposal examines the functions of a group of proteins belonging to the p120-catenin sub-family, that we have evidence and hypothesize participates in Wnt signaling, and whose study will assist in understanding of both normal development and human disease.