PLAKOGLOBIN ORTHOLOGUES AND THE CELL

描述（改编自申请人摘要）：我们目前的假设是， 对Wnt信号的特异性反应由斑珠蛋白和 β-连环蛋白以依赖于它们的其他蛋白质缔合的方式， 修改.初步结果表明：（1）转基因表达 斑珠蛋白抑制毛发生长;（2）β-连环蛋白的转基因表达 在乳腺中产生肿瘤;（3）斑珠蛋白是糖基化的， 推测的CSK-3 β磷酸化位点。我们的目标如下 问题：（1b）斑珠蛋白是否具有拮抗、协同或 与β-连环蛋白互换来调节正常细胞的细胞生长？ 将建立K14-deltaN 89 β-连环蛋白小鼠，并比较它们的毛发表型 现有的K14-deltaN 80-斑珠蛋白小鼠。自发性肿瘤发生率 现有的MMTV-deltaN 89 β-连环蛋白和MMTV-deltaN 80-斑珠蛋白小鼠将 被比较。拮抗作用或协同作用将通过这些化合物的交叉在体内测试。 通过检测培养的转基因角质形成细胞， 表达一个转基因对细胞定位、稳定性和 另一转基因产物的相互作用。(1b)上调了 斑珠蛋白激活FGFR？K14-deltaN 80-斑珠蛋白小鼠将被饲养以 FGF 5-/-安哥拉小鼠寻找长毛表型的抵消作用， 两条路径交叉的证据K14-deltaN 80-转基因斑珠蛋白 将检查角质形成细胞的钙粘蛋白的上调和 作为潜在FGFR配体的FGF的上调。(2)斑珠蛋白和 β-连环蛋白上调使表皮易于发生肿瘤？一组 将筛选化学诱导的皮肤肿瘤的上调， 斑珠蛋白和β-连环蛋白的重新定位和突变。K14转基因小鼠 将通过以下方法检测对肿瘤诱导的增强或抑制易感性： (a)对表达v-rasHa的小鼠进行繁殖：（b 0转化转基因 角质形成细胞与v-rasHa和移植到无胸腺小鼠;（c）标准化学 致癌方案。(3)斑珠蛋白的糖基化是否在 蛋白质稳定性，连接形成和Wnt信号转导？亚细胞组分 角质形成细胞+/-连接形成和PC 12细胞+/- wnt表达将 检查斑珠蛋白糖基化的存在和程度。

DESCRIPTION (Adapted from applicant's abstract): Our current hypothesis is that specific responses to Wnt signals are determined by both plakoglobin and beta-catenin in a manner dependent on their other protein associations and modifications. Preliminary results show that (1) transgenic expression of plakoglobin inhibits hair growth; (2) transgenic expression of beta-catenin produces tumors in mammary gland; (3) plakoglobin is glycosylated in the putative CSK-3beta phosphorylation site. Our aims address the following questions: (1b) does plakoglobin act antagonistically, synergistically or interchangably with beta-catenin to regulate cell growth in normal cells? K14-deltaN89beta-catenin mice will be created and their hair phenotype compared to the existing K14-deltaN80-plakoglobin mice. The spontaneous tumor incidence of existing MMTV-deltaN89beta-catenin and MMTV-deltaN80-plakoglobin mice will be compared. Antagonism or synergy will be tested in vivo by crossing of these pairs of mice and in vitro by examining cultured transgenic keratinocytes for the effects of expressing one transgene on the localization, stability and interaction of the produce of the other transgene. (1b) does up-regulated plakoglobin activate FGFR? K14-deltaN80-plakoglobin mice will be bred to FGF5-/- angora mice to look for counteraction of the long hair phenotype as evidence of intersection of the pathways. K14-deltaN80-plakoglobin trangenic keratinocytes will be examined for up-regulation of cadherins and for up-regulation of FGFs as potential FGFR ligands. (2) Does plakoglobin and beta-catenin up-regulation predispose epidermis to tumorigenesis? A panel of chemically induced skin tumors will be screened for up-regulation and relocation and mutations of plakoglobin and beta-catenin. K14 transgenic mice will be tested for enhanced or suppressed susceptibility to tumor induction by (a) breeding to mice expressing v-rasHa: (b0 transforming transgenic keratinocytes with v-rasHa and grafting to athymic mice; (c) standard chemical carcinogenesis protocols. (3) does glycosylation of plakoglobin play a role in protein stability, junction formation and Wnt-signaling? subcellular fractions of keratinocytes+/- junction formation and PC12 cells +/- wnt expression will be examined for presence and extent of plakoglobin glycosylaiton.