Structure and expression of fyn genes in Xenopus laevis.
Structure and expression of fyn genes in Xenopus laevis.
复制标题
非洲爪蟾 fyn 基因的结构和表达。
作者：
R. Steele;Deng Jc;Corine Ghosn;Fero Jb
通过低严格筛选非洲爪蟾卵母细胞cDNA文库与探针制备的禽逆转录病毒Y73的是癌基因，我们已经分离克隆编码537个氨基酸的蛋白质与96%的氨基酸同一性的蛋白质产物的人fyn原癌基因。除了在氨基酸序列水平上的高度保守性之外，我们还发现青蛙和人类基因的5'非翻译区部分之间的序列保守性令人惊讶地高。探针的总DNA从一个纯合子二倍体青蛙的cDNA克隆的片段得到了杂交模式，这是一致的存在下，两个fyn基因的单倍体非洲爪蟾基因组。杂交分析表明，卵巢含有两个不同大小的fyn RNA，一个长度为3.8 kb，另一个长度为3.1 kb。我们对fyn转录本的发现使src家族的蛋白酪氨酸激酶的数量增加到三种，而src家族的mRNA在X.卵母细胞这表明多种src家族的蛋白酪氨酸激酶是卵子发生或早期发育过程所必需的。
By low stringency screening of a Xenopus laevis oocyte cDNA library with a probe prepared from the yes oncogene of the avian retrovirus Y73, we have isolated clones encoding a 537 amino acid protein with 96% amino acid identity to the protein product of the human fyn proto-oncogene. In addition to the high degree of conservation at the amino acid sequence level, we also find a surprisingly high degree of sequence conservation between portions of the 5' untranslated regions of the frog and human genes. Probing of total DNA from a homozygous diploid frog with a fragment from one of the cDNA clones gave a hybridization pattern which is consistent with the presence of two fyn genes in the haploid Xenopus laevis genome. Hybridization analysis revealed that the ovary contains two different sized fyn RNAs, one 3.8 kb in length and the other 3.1 kb in length. Our finding of fyn transcripts brings to three the number of protein-tyrosine kinases of the src family whose mRNAs are found in X. laevis oocytes. This suggests that multiple protein-tyrosine kinases of the src family are required for processes in oogenesis or early development.