MAMMALIAN GENES ENCODING ENHANCER OF SPLIT GROUCHO PROTEIN

在果蝇Drosophila melanogaster中， 控制几个位点，包括分裂增强子，其产物 似乎决定了胚胎期神经外胚层细胞的命运 发展这些基因似乎在以下方面发挥重要作用： 精子发生和神经发生。编码该蛋白的cDNA 分裂型Groucho增强子（ESG）及其相关氨基末端（AES） 从人、小鼠和非洲爪蟾中分离蛋白质并测序。的 ESG蛋白由771个氨基酸组成，而AES蛋白含有 197个氨基酸。发现AES蛋白表现出约50%的 与果蝇分裂增强子氨基末端区域的同一性 Groucho蛋白质人类AES和两个ESG基因已经使用人类基因定位。 和中国仓鼠杂交细胞系染色体19，9和15， 分别用荧光法对人AES基因进行了进一步定位 染色体19p13.3带原位杂交， 蛋白质编码序列被六个内含子中断。北方斑点 分析表明，ESG1的2.8kb的RNA广泛表达，ESG2的2.8kb的RNA广泛表达。 在成年爪蟾组织中检测到3.6kb和2.2kb的SES， 而ESG1和AES转录本分别为2.8kb和2.2kb， 在非洲爪蟾胚胎发育中广泛表达。的 分析了AES和ESG基因之间的进化关系。 脊椎动物AES和ESG蛋白的生理功能 精子发生、卵子发生和胚胎发生，包括神经发生， 正在调查

In the fruitfly Drosophila melanogaster, neurogenesis is under the control of several loci, including Enhancer of split, whose products appear to determine the fate of neuroectodermal cells during the embryo development. These genes appear to play significant roles in spermatogenesis in addition to neurogenesis. The cDNAs encoding the enhancer of split groucho (ESG) and its related amino-terminal (AES) proteins were isolated and sequenced from human, mouse and Xenopus. The ESG proteins consist of 771 amino-acids, while the AES proteins contain 197 amino-acids. The AES proteins were found to exhibit approximately 50% identity to the amino-terminal region of Drosophila enhancer of split groucho protein. Human AES and two ESG genes have been mapped using human and Chinese hamster hybrid cell lines to chromosomes 19, 9 and 15, respectively. Human AES gene was further localized by fluorescence in-situ hybridization to chromosome band 19p13.3, and its protein-encoding sequence is interrupted by six introns. Northern blot analysis showed that widespread RNA expression of ESG1 of 2.8kb, ESG2 of 3.6kb and SES of 2.2kb transcripts were seen in adult Xenopus tissues, whereas ESG1 and AES transcripts of 2.8kb and 2.2kb, respectively, were ubiquitously expressed in the developing Xenopus embryos. The evolutionary relationships among these AES and ESG genes were analyzed. The physiological function(s) of vertebrate AES and ESG proteins during spermatogenesis, oogenesis, and embryogenesis, including neurogeneis, are being investigated.