真核生物的V形基因调控模型和基因调控关系的预测

我们研究发现,有些果蝇基因的外显子和插入序列的碱基组成没有明显区别.这种基因编码的蛋白质C-末端氨基酸序列与其转录的mRNA尾随片段高度亲和.这种母基因与其编码的子蛋白质高度亲和的特性,我们称为母子相亲机制.用这些基因的尾随片段进行同源搜索,然后再分析同源序列所在位置的RNA结构,结果发现:1)位于基因启动子位置的,其结构为茎环结构,说明该同源序列是基因启动子的重要组成部分;2)位于插入序列中的,出现了一种象钥匙一样的结构,它的一端为回文形成的茎环结构,为钥匙的柄,另一端为单链结构,为钥匙的舌.这两种序列可能参与了基因的调控.由此,我们建立了一个的V形的基因调控模型.这个模型包括3个主体:被控基因、编程基因、启动基因.编程基因提供蛋白质与被调控基因的启动子序列结合,决定被调控基因是否可以表达的.而启动基因转录成的RNA通过剪切等加工,产生一种结构象钥匙的microRNA(miRNA),它可以启动被调基因.根据母子相亲机制和V形调控模型,以及回文规则,我们设计出了一种尾随片段搜索筛选法,预测真核生物基因的互控关系.

V-shaped Gene Regulation Model and Prediction of Gene Regulation Relationships of Eukaryotes

We discovered that there is not an obvious difference between the base components of extrons and intervening sequences of some Drosophila melanogaster genes.The proteins' C terminal amino acid sequences encoded by these genes are highly affinitative with the mRNAs' tail segments transcribed from these,which is called the mother sub affinity mechanism (MSAF) that mother DNAs and the sub proteins encoded by them are highly affinitative.We concluded the following two important findings by searching Drosophila melanogaster's nucleotide database for the similar sequences of the tail segments and analyzing the RNA structures of the sites of the similar sequences:(1) if the sites are in gene promoters,the structures are of stem and loops,indicating that the similar sequences are the important parts of the gene promoters;(2) if the sites are in insertion sequences,the structures are like keys with their petioles of stem and loop structures and their tongues of single strand structures.These two kinds of sequences may participate in gene regulation.Therefore,we built a V shaped gene regulation model (V GRM) mainly composed of a controlled gene,programmer gene and promotion gene.The protein encoded by the programmer gene binds to the controlled gene,determining whether the controlled gene can be expressed;the RNA transcribed from the promotion gene produces a key like miRNA by processing reactions such as splicing,promoting the expression of the controlled gene.According to MSAF,V GRM and the palindrome rule,We designed a tail segment searching filtration method,predicting gene regulation relationships of eukaryotes.