THE FUNCTION OF THE ENDOTHELIN FAMILY IN NEURAL CREST DEVELOPMENT: AN IN VITRO SY

突变的小鼠致死斑点(Ls)编码血管活性多肽内皮素3(EDN3)，花椒(S)基因座编码其受体内皮素B受体(EDNRB)。这些基因突变纯合的小鼠表现出无神经节细胞的巨克隆和白色斑点的被毛，这是因为在受影响的结肠和皮肤部分缺乏神经脊源性肠神经节和黑素细胞。为了了解这些基因在黑素细胞发育中的作用，我们正在使用原位杂交来确定这些基因在突变胚胎和正常胚胎中相对于其他神经脊标记的表达时间。我们已经证明，这两个基因在小鼠胚胎发育非常早的时候就在神经脊来源的细胞中表达，并且在各种神经脊突变体中的表达模式发生了变化。我们已经确定，在我们开发的体外系统中，外源添加的EDN3改变了黑素细胞的增殖和分化。我们发现EDN3可以成功地取代TPA在这个系统中，并导致黑素细胞增加50倍。我们发现在相关的家族成员(EDN1和EDN2)中，只有EDN1可以替代EDN3。我们还表明，EDN3的作用依赖于其受体EDNRB在使用化学抑制剂的神经脊细胞上的存在。-生物技术研究、癌症研究、消化系统疾病、基因图谱(非人类)、神经科学、儿科研究、

The mouse mutant lethal spotting (ls) encodes the vasoactive peptide endothelin 3 (EDN3) and the piebald (s) locus encodes its receptor, endothelin receptor B (EDNRB). Mice homozygous for mutations in either of these genes exhibit aganglionic megaclon and a white spotted coat due to the lack of neural-crest derived enteric ganglia and melanocytes in affected portions of the colon and skin. In order to understand the role of these genes in melanocyte development, we are using in situ hybridization to determine the time that these genes are expressed relative to other neural crest markers in mutant and normal embryos. We have shown that both genes are expressed very early during mouse embryonic development in neural crest derived cells and expression patterns are altered in various neural crest mutants. We have determined that exogenously added EDN3 alters promotes proliferation and differentiation of melanocytes in an in vitro system that we have developed. We have found that EDN3 can successfully replace TPA in this system and results in a 50 fold increase in melanocytes. We have found that of the related family members (EDN1 and EDN2) only EDN1can substitute for EDN3 in this assay. We have also shown that the effect of EDN3 is dependent upon the presence of its receptor EDNRB on neural crest cells by using chemical inhibitors. - biotechnology research, cancer research, digestive diseases, gene mapping(non-human), neuroscience, pediatric research,