CONTROLLING THE ACTIVITY OF A DROS TGF BETA HOMOLOG

这项研究的目的是在分子水平上了解如何 在显影期间指定并解释位置信息。 tolloid（tld）和scw（scw）基因产物所起的作用， 在指导背/腹（D/V）图案形成的过程中， 地方将研究黑腹胚胎。 tld和scw中的突变 导致胚盘命运图的背侧移位， 胚胎的腹侧化。 遗传分析表明， scw的作用是增强第三个D/V模式基因的活性 十肢麻痹（dpp），其产物（DPP）是TGF-β的成员， 生长因子超家族。 TGF-β家族的分泌 多肽介导多种细胞间通讯， 似乎控制着广泛的生物过程 包括细胞生长和分化。 具体目标是 建议是：1）生物化学特性的蛋白质。2)到 检查TLD-DPP相互作用的性质，以及3）从分子水平 表征SCW基因座。 DNA序列分析显示，tld与人类骨骼有45%的相同性 形态发生蛋白-1（BMP-1），一种假定的金属蛋白酶。 杆状病毒 表达系统将用于大量生产TLD蛋白。 将测定纯化的酶的蛋白酶活性、金属离子需求， 和自缔合特性。 定点突变和可用的TLD 分析等位基因对这些性质的影响。 为了寻找TLD-DPP复合物，将产生针对 不同的部分，并用于共沉淀沉淀物， 来自卵黄周液和来自组织培养细胞的蛋白质， 民进党和民进党。 将通过以下方式监测联合检查组处理DPP的能力： 共表达蛋白的SDS-PAGE电泳。 对于scw，转录单位将通过P元件介导的 转化和将螺旋mRNA注射到突变胚中。 一 将对代表性cDNA进行测序并分析其是否存在 同源性可能为scw基因的生物学功能提供线索 产品 抗体将被产生并用于检查组织 基因产物的分布和亚细胞定位。 这些 研究将有助于我们理解空间信息是如何 在开发过程中指定，并可能提供一个范例， TGF-β家族成员的活性在其他生物体中受到调节， 流程.

The purpose of this research is to understand at the molecular level, how positional information is specified and interpreted during development. The roles played by the tolloid (tld) and screw (scw) gene products (TLD), SCW) in the process that directs dorsal/ventral (D/V) pattern formation in the D. melanogaster embryo will be investigated. Mutations in tld and scw cause a dorsal shift in the blastoderm fate map resulting in a partial ventralization of the embryo. Genetic analysis suggests that both tld and scw act to boost the activity of a third D/V patterning gene decapentaplegic (dpp), whose product (DPP) is a member of the TGF-beta superfamily of growth factors. The TGF-beta family of secretory polypeptides mediate intercellular communication in a multitude of organisms and appear to control a wide range of biological processes including cell growth and differentiation. The specific aims of this proposal are: 1) to biochemically characterize the TLD protein. 2) to examine the nature of the TLD-DPP interaction, and 3) to molecularly characterize the scw locus. DNA sequence analysis has revealed that tld is 45% identical to human bone morphogenetic protein-1 (BMP-1), a putative metalloprotease. A baculovirus expression system will be use to produce large quantities of TLD protein. Purified TLD will be assayed for protease activity, metal ion requirements, and self association properties. Site-directed mutations and available tld alleles will be assayed for effects on these properties. To search for TLD-DPP complexes, antibodies will be raised against different parts of TLD and used to coprecipitate TLD and associated proteins from perivitelline fluid and from tissue culture cells expressing both TLD and DPP. The ability of TLD to process DPP will be monitored by SDS-PAGE electrophoresis of co-expressed proteins. For scw the transcription unit will be identified by P element mediated transformation and by injection of screw mRNA into mutant embryos. A representative cDNA will be sequenced and analyzed for the presence of homologies which may give a clue to the biological function of the scw gene product. Antibodies will be generated and used to examine the tissue distribution and subcellular localization of the gene product. These studies will contribute to our understanding of how spatial information is specified during development and may provide a paradigm for how the activity of TGF-beta family members is regulated in other organisms and processes.