GENES THAT CONTROL EARLY EMBRYOGENESIS

这项提议所基于的假设是 推测原癌基因int-2在肿瘤发生、发展中起重要作用。 哺乳动物早期胚胎发育的控制。数据来自我们的 INT-2在小鼠胚胎和胚胎中表达的研究进展 畸胎癌细胞显示有四种 胚胎转录本，它们的表达是不同的 在正常胚胎发育过程中和在 畸胎瘤干细胞体外分化的研究。我们 建议克隆和鉴定这四个胚胎INT-2基因 RNA。他们的蛋白质产品将通过使用一种 细菌表达载体系统和抗INT-2抗体将 被抚养长大。在中国获得的核酸和免疫学探针 然后这些研究将被用来确定阶段和细胞 胚胎中INT-2表达的类型特异性。特别是， 我们将确定胚胎中哪些细胞表达该基因和 其产品的亚细胞位置(S)。如果它是一个秘密的 蛋白质，我们将确定它在胚胎中的位置 本地化。最后，我们提出了一系列实验，旨在 决定更改或废除 Int-2在畸胎癌细胞和/或胚胎中的表达。这样做的结果 研究应该为我们提供信息，使我们能够 确定INT-2在胚胎中的功能，进而 应该有助于更好地理解控制 正常的胚胎发育。此外，我们预计 了解该基因的正常功能将提供一些 洞察为什么这种原癌基因在卵巢癌中异常表达 乳腺会导致癌变。

The hypothesis on which this proposal is based is that the presumed proto-oncogene int-2 plays an important role in the control of early mammalian embryogenesis. Data from our previous study of int-2 expression in mouse embryos and teratocarcinoma cells demonstrated that there are four embryonic transcripts and that their expression is differentially regulated during normal embryogenesis and during the course of differentiation of teratocarcinoma stem cells in vitro. We propose to clone and characterize these four embryonic int-2 RNAs. Their protein products will be obtained by the use of a bacterial expression vector system, and anti-int-2 antibodies will be raised. The nucleic acid and immunological probes obtained in these studies will then be used to determine the stage- and cell type- specificity of int-2 expression in the embryo. In particular, we will determine which cells in the embryo express the gene and the subcellular location of its product(s). If it is a secreted protein, we will determine where in the embryo it becomes localized. Finally, we propose a series of experiments aimed at determining the effect of altering or abolishing the expression of int-2 in teratocarcinoma cells and/or embryos. The results of this study should provide us with information that will enable us to determine the function of int-2 in the embryo, which in turn should lead to a better understanding of the processes that control normal embryonic development. Furthermore, we anticipate that knowledge of the normal function of the gene will provide some insight into why abnormal expression of this proto-oncogene in the mammary gland results in carcinogenesis.