Summary: | 碩士 === 中山醫學大學 === 生物醫學科學學系碩士班 === 104 === In recent years, many studies have found that the methylations on histone and other proteins are involved in the regulation of gene transcription. Protein methylation is a covalent post-translational modification. It plays a very important role in cell growth, regulation of gene expression and signal conduction. It has been found a variety of PRMT substrate including histone and non-histone protein as well as preferred structure of PRMT. However, the particular structure of PRMT and specific target amino acid sequences have not been studied extensively. The objectives of the present study were to use bioinformatics method to explore the sequence position of protein arginine methylation, surrounding structure and relationship between the various class of PRMT. Meanwhile, we used the software to predict post-translational modification site such as phosphorylation sites. Finally, we will analyze the possible interactions among those post-translational modifications. According to the previous studies, we collected more than 1000 protein arginine methylation sites derived from 807 protein sequences. These proteins were subjected to a BLAST-Based Relative Distance (BBRD) tool to evaluate the evolutionary relationship among those proteins, then to identify the consensus arginine methylation target sequences for the sub-tree. After screening out this sequence to generate 21 subgroups which using PRATT software to search for patterns conserved in each subgroup. It produced 15 group of conserved sequence. Furthermore, we organize many type of substrate protein and compare with PRATT result. These patterns compare with previous studies of PRMT substrate whether arginine methylation sequence is consistent.
The results showed that nearly 60 percent of the phosphorylation sites are within 10 residues of the methylation sites, indicating the possibility that phosphorylation and methylation may affect each other. The analysis of substrate sequence specificity remain poorly understood that PRMT recognize which pattern of sequence, but this approach shows the possibility of research.
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