GENETIC CONTROL OF MAMMALIAN CELL SURFACE FUNCTIONS

该研究项目的最终目标是确定遗传和 受体介导的信号传递机制的分子基础 多肽激素和生长因子，特别是胰岛素和表皮生长因子， 组织培养细胞中的EGF。 我们也有兴趣 肿瘤促进剂的生长促进活性。 我们正在接近 提出的目标是通过使用体细胞诱变， 结合分子生物学和生物化学技术。 通过 选择在各个步骤中有缺陷或异常的突变体， 胰岛素、EGF和肿瘤的作用机制 启动子，我们希望在基因上定义和表征该途径 和生物化学。 此外，我们利用这些遗传变异来绘制 参与激素结合、内化和 细胞内加工，受体的聚集和回收，以及各种 通过细胞杂交分析检测受体后功能。 具体目标 我们的研究是：（1）继续表征的 分离的遗传变异，以确定其遗传和生化 病变;（2）细胞内的命运，毒素缀合物，以更好地 了解它们的进入机制;（3）分离新的一系列变体 通过将细胞毒性缀合物应用于诱变的细胞 在细胞周期的某个阶段同步化的群体，或 暂时用内吞机制的特异性抑制剂处理;（4） 在分离的变体之间或与其他细胞形成细胞杂交体 进行互补组分析和染色体定位， 相应基因;（5）人类受体基因的定位， 胰岛素、TGF、MSA和IGFs的交联技术;（6） EGF受体在A431中过量产生的遗传和分子基础 细胞，特别是易位染色体M4和 产生截短的变体3 kb mRNA和110 kd EGF受体片段; (7)检查可能的染色体重排和基因 各种人类肿瘤源细胞的过度产生或改变 使用EGF受体/erbB的cDNA探针检测EGF受体缺陷 癌基因 转化生长因子家族的新发现 与癌基因产物的关系意味着一种复杂的基因调控， 它们的受体系统 尽管细胞遗传学方法 受体系统仍处于起步阶段，它提供了独特的实验 研究细胞生长调节的系统。

The ultimate goal of this research project is to determine the genetic and molecular basis of receptor-mediated signal transfer mechanisms of polypeptide hormones and growth factors, particularly insulin and epidermal growth factor (EGF) in tissue cultured cells. We are also interested in the growth promoting activity of the tumor promoters. We are approaching the proposed goals through the use of somatic cell mutagenesis in combination with molecular biological and biochemical techniques. By selecting mutants that are defective or extraordinary in the various steps of the mechanisms involved in the action of insulin, EGF and tumor promoters, we hope to define and characterize the pathway both genetically and biochemically. Furthermore, we utilize these genetic variants to map genes that are involved in hormone's binding, internalization, and intracellular processing, receptor's clustering and recycling, and various post-receptor functions by cell hybridization analysis. Specific aims of our investigation are the following: (1) continued characterization of the isolated genetic variants to determine their genetic and biochemical lesions; (2) intracellular fate of the hormone-toxin conjugates to better understand their entry mechanisms; (3) isolation of new series of variants by the application of cytotoxic conjugates to the mutagenized cell populations which are synchronized at a certain stage of cell cycle or temporarily treated with specific inhibitors of endocytic mechanisms; (4) formation of cell hybrids between the isolated variants or with other cells to perform complementation group analysis and chromosomal localization of the corresponding genes; (5) mapping of the human receptor genes for insulin, TGFs, MSA, and IGFs by crosslinking techniques; (6) studies on the genetic and molecular basis of the EGF receptor-overproduction in A431 cells, particularly the relation between translocation chromosome M4 and production of truncated variant 3kb mRNA and 110kd EGF receptor fragments; (7) examination of the possible chromosome rearrangements and gene alterations in various human tumor-derived cells which are overproducing or deficient in EGF receptors using cDNA probes for EGF receptor/erbB oncogene. The recent discovery of a family of transforming growth factors in relation to oncogene products implies a complex genetic regulation of their receptor systems. Although the cell genetic approach to these receptor systems is still in its infancy, it provides unique experimental systems by which regulation of cell growth is studied.