水稻螟虫神经肽PBAN及其受体序列的生物信息学分析

Bioinformatic analysis of PBAN and its receptor proteins in rice stem borers

【目的】性信息素合成激活肽（PBAN）是控制昆虫产生性信息素的激素,本文旨在分析水稻螟虫神经肽PBAN及其受体的序列。【方法】通过t Blastn同源检索从水稻螟虫基因组和转录组数据库中鉴定水稻螟虫PBAN神经肽及其受体序列,在此基础上进行序列比对及系统发生分析。【结果】发现二化螟Chilo suppressalis、三化螟Tryporyza incertulas和大螟Sesamia inferens的PBAN成熟肽序列均含有33个氨基酸残基,其C端五肽序列完全相同,3种水稻螟虫PBAN多肽相似度为54.55%~63.64%;发现二化螟PBAN受体3个异构体全长氨基酸序列（PBANR-A、PBANR-B和PBANR-C）,均含有7个跨膜区域。【结论】进化树分析发现不同昆虫PBAN神经肽及其受体存在一定的保守性和多样性,并且在进化树上的位置几乎与昆虫系统发育分类一致,推测PBAN神经肽和PBAN受体在昆虫系统进化过程中可能存在协同进化现象。本研究为水稻螟虫PBAN神经肽及其受体的结构和功能分析提供基础。

[Objectives] To determine the amino acid sequences of pheromone biosynthesis activating neuropeptide（PBAN）, a hormone that controls the synthesis of insect sex pheromones, and its receptor proteins, in rice stem borers. [Methods] We used t Blastn searching of the rice pest genome and transcriptome databases to predict sequences of PBAN and its receptors in rice stem borers after which sequences were aligned and a phylogenetic tree constructed. [Results] The mature peptide sequences of PBAN in the rice stem borers, Chilo suppressalis, Tryporyza incertulas and Sesamia inferens, contain 33 amino acid residues, and have the same five peptide sequences in the C-terminal. The similarity of PBAN polypeptides in these three insects was 54.55%-63.64%. The sequences of three isoforms of the PBAN receptor（PBANR-A, PBANR-B and PBANR-C） in C. suppressalis were predicted from the C. suppressalis transcriptome database. All three isoforms contain seven transmembrane regions. [Conclusion] Phylogenetic analysis based on between-species variation in PBAN confirms the established taxonomic relationships among rice stem borer species. The phylogenetic relationships between the PBANs of different rice stem borers, or their receptors, are almost identical to the established phylogenetic relationships between these insects, suggesting co-evolution between insect PBAN, and its receptors, during the process of insect evolution. This study provides a basis for analyzing the function of PBAN, and its receptors, in rice stem borers.