番茄组蛋白乙酰转移酶(HAT)的全基因组鉴定与分析

史建磊 熊自立 李涛 张海利 宰文珊

摘要：組蛋白乙酰化修饰在基因表达调控方面扮演着重要角色。为深入挖掘番茄组蛋白乙酰转移酶（HAT）基因，本研究运用生物信息学方法，共鉴定出26个番茄HAT。聚类分析发现，这些HAT可以分为7组，分别为HAG、HAG1、HAG2、MCC1、HAM、HAF和HAC。其中，GNAT家族（GCN5、HAT1、MCC1） 18个、p300/CBP家族4个、MYST和TAFII250家族各1个。6对同源基因Ka/Ks值均小于1，说明其进化中经历了纯化选择。不同家族HAT理化性质存在差异，但均为亲水蛋白质，主要定位于细胞核，蛋白质二级结构主要包括α螺旋和无规则卷曲，具有典型的保守基序和特征结构域。染色体定位发现，番茄HAT基因不均匀地散布于12条染色体上，且呈两端分布，其中1号和9号染色体最多，部分基因经串联重复形成基因簇。基因表达分析发现，GNAT家族番茄特有的HAT和HAG2组基因在病菌、盐和热胁迫下具有较高的表达水平，一些基因具有病菌诱导特异性和耐盐（热）与盐（热）敏材料上表达差异性。可见，番茄HAT在结构、性质和功能上具有多样性，其在全基因组水平上的鉴定与分析为相关基因克隆利用提供了依据。

关键词：番茄;组蛋白乙酰转移酶;生物信息学

中图分类号：Q786文献标识码：A文章编号：1000-4440（2020）03-0666-09

Genome-wide identification and analysis of histone acetyltransferase （HAT） in tomato

SHI Jian-lei1，XIONG Zi-li1，LI Tao2，ZHANG Hai-li1，ZAI Wen-shan1

（1.Wenzhou Vocational College of Science and Technology， Wenzhou 325006， China;2.Vegetable Research Institute， Guangdong Academy of Agricultural Sciences， Guangzhou 510640， China）

Abstract： Histone acetylation plays an important role in the regulation of gene expression. In order to further explore histone acetyltransferase （HAT） gene in tomato， 26 HAT genes were identified by using bioinformatics method in this study. The results of cluster analysis showed that these HAT could be divided into seven groups， namely HAG， HAG1， HAG2， MCC1， HAM， HAF and HAC. Among them， 18 HAT genes were GNAT family members （GCN5， HAT1， MCC1）， four HAT genes were p300/CBP family members， and one was MYST or TAFII250 family member. The Ka/Ks values of six pairs of paralogous genes were all less than one， indicating that purifying selection had occurred in evolution. The physicochemical properties of HAT in different families were different，but all of them were hydrophilic proteins， mainly located in the nucleus. Furthermore， the secondary structure of proteins mainly included alpha helix and random coil， and had typical conserved motifs and domains. Chromosome localization results showed that tomato HAT gene were unevenly distributed on 12 chromosomes and at both ends. In addition， the number of chromosome 1 and 9 was the most， and some genes formed gene clusters by tandem duplication. Results of gene expression analysis indicated that the HAT genes， which were unique in tomato， and HAG2 gene， had higher expression levels under pathogen， salt and heat stress. Also， some genes had pathogen-inducible specificity and different expression levels between resistant and sensitive materials. It can be seen that HAT gene in tomato  has diversity in structure， character and function， and the genome-wide identification and analysis results providea basis for cloning and utilization of related genes.

Key words：tomato;histone acetyltransferase （HAT）;bioinformatics

植物在生长发育过程中面临着各种生物与非生物胁迫，同时，在长期历史进化中植物本身也形成了多种调控与防御机制，来保障个体正常生长发育与群体繁衍。组蛋白修饰在基因表达调控方面扮演着重要角色，通过组蛋白乙酰转移酶（HAT）促进基因表达和组蛋白去乙酰化酶（HDAC）抑制基因表达。……