The Research Of Alternative Splicing On Gene Function And Protein Structure

Alternative splicing is a basic and important regulatory mechanism in eukaryotic genome.Through alternative splicing, the gene sequences produce a variety of different mRNA isoforms. These mRNA isoforms were eventually translated into different protein product or antagonistic structure and function. The different levels of expression can produce different phenotypes, even in the same cell. Only 20,000 to 25,000 genes exist in human, whereas occurrence of alternative splicing events can created a rich, complex physiological functions.Therefore, the study of alternative splicing events help to reveal functional mechanisms of the human organism and understand the nature of human life.Genes determine biological traits through carrying genetic information. However,Protein is the executor of the biological function in the body. Gene sequences determine the sequence of amino acids. The sequences of amino acids determine the structure of protein and the structural state of the protein determines function of the protein. Therefore,there has an important relation between structure of protein and gene. Changes in gene sequences may lead to vary in protein sequence, thereby affecting the structure and function of proteins.Occurrence of alternative splicing events can change the gene sequence, which means that it will have a major impact the structure and function of protein. From this perspective, this paper analyzes alternative splicing for gene function and its effect on protein structure. This paper includes the following four aspects:(1) Due to the uncertainty of alternative splicing events, this paper need to do pre-processing on the alternative splicing events. First of all, analyzing the data of alternative splicing events. Then, establishing the judgment rules on estimating the effectiveness of alternative splicing events data. Finally, based on the judging rules, this paper analysis and process the alternative splicing events data and extract all the alternative splicing event data that comply with the rules, which are used for further research in this paper.(2) Analyzing of gene function of alternative splicing events. Firstly, according to the alternative splicing events information annotation for gene information. On the basis of alternative splicing events to the influence degree of the gene codon, then separating the alternative splicing events into two categories. Group Ⅰ change the original frame encoding of the alternative splicing events and group Ⅱ retain the original coding frame of the alternative splicing events. Next, this paper use GO to do the function analysis of the selected alternative splicing events, Finally, this paper compare the two groups based on the GO annotation. The results show two types of gene splicing events have the most catalytic activity,followed by binding, at least channel regulator activity. Moreover compare two types of splicing events found no significant difference in gene function.(3) Building a model that can translate the gene sequences to the amino acid sequences for the alternative splicing events. Firstly, this paper introduce the molecular mechanism of alternative splicing, then, proposing the rules on the translation from gene sequences into amino acid sequence for the alternative splicing events. Finally, according to these rules, this paper carried the translation. This article finally obtained 39541 amino acid sequence.(4) Analysis the impaction of alternative splicing events on the protein structure. Using VSL2 disordered protein structure prediction model to predict the disorder probability for the protein of alternative splicing, Also predicted disordered region length distribution. Then,according to the prediction results,alternative splicing makes protein product have a tendency of disordered structure.