摘要
CBF(C-repeat binding factor)是AP2家族的一类转录激活因子,在植物响应低温胁迫和提高植物耐寒性方面具有重要作用。虽然多个石榴品种的基因组已经发布,但仍缺乏对其CBF基因家族的全面研究。为全面分析石榴(Punica granatum L.)CBF基因家族分子生物学特性,本文对鉴定到的PgCBFs成员进行了生物信息和表达分析。结果表明,石榴全基因组中有7个CBF基因家族成员,蛋白序列中除包含AP2结构域外,还具有CBF特征序列PKKPAGRxKFxETRHP和DSAWR;7个成员集中分布在染色体1和4上,编码蛋白质氨基酸长度为201~267aa,分子质量为21.69~29.81ku;进化分析显示PgCBFs基因家族成员分布在GroupⅡ~Ⅳ亚组中,与水稻CBF成员组成的GroupⅠ存在明显区分;除PgCBF2、PgCBF4、PgCBF5基因结构中含有1~2个内含子外,其余与其他物种类似,属内含子缺失型;编码的蛋白序列均含有保守基序Motif1~7;蛋白二级结构主要为不规则卷曲和α-螺旋,三级结构较为相似。PgCBFs基因家族扩增主要来源于串联重复,并与拟南芥、苹果、桃分别存在2对、5对和4对共线性关系;GO注释显示PgCBFs多与转录调控、低温胁迫或激素诱导相关;启动子区含有多种顺势作用元件,主要为胁迫刺激、激素诱导和光响应元件;基因表达分析发现除PgCBF6外,其余成员在根中高度表达,在低温胁迫处理下PgCBF在根和韧皮部表达量显著上调,其中PgCBF7能够快速响应并持续应答低温诱导。结合进化树、共线性、启动子以及表达分析,推测PgCBF7可能与石榴幼苗低温胁迫调控相关。本研究可为深入研究石榴CBF基因家族生物学功能提供理论基础。
As a class of AP2 family transcription factors, C-repeat binding factor(CBF) gene family plays an important role in resisting low-temperature stress and improving cold tolerance of plants.The genome of pomegranate is released, but a comprehensive study on its CBF genes family is still lacking.In order to characterize the CBF gene family of pomegranate(Punica granatum L.),PgCBF family genes were comprehensively analyzed by using bioinformatics methods and qRT-PCR.In this study, the total of seven pomegranate CBF genes were from pomegranate genome.Sequences alignment revealed that all the CBF proteins contained AP2 DNA-binding domain, signature sequences PKKPAGRxKFxETRHP and DSAWR,respectively.These PgCBFs were mainly distributed on chromosome 1 and 4,respectively.The number of coding amino acid of PgCBFs was 201-267 aa, and the molecular mass was 21.69-29.81 ku.Phylogenetic analysis showed that PgCBFs were divided into Group Ⅱ-Ⅳ,which were clearly distinguished from Group Ⅰ that was composed of OsCBFs.Except PgCBF2, PgCBF4, PgCBF5 contained 1-2 intron, the other members of PgCBF family genes were intron-less type, which were similar with other six species.MEME results showed that Motif 1-7 were conserved and presented in CBF protein sequences of all seven species.Secondary structure of the PgCBFs protein was mainly composed of random coils and alpha helix, and their three-dimensional structure was relatively similar each other.The syntenic analysis indicated that tandem repeat may play a major role in expansion of PgCBF gene family, and syntenic relationships showed that PgCBF gene had two, five and four syntenic gene pairs with Arabidopsis,apple and peach, respectively.GO annotation analysis indicated that some PgCBFs genes participated in transcriptional regulation, low-temperature stress or hormone induce response.The analysis of cis-acting elements showed that there were various cis-acting elements related to stress, hormone, and light.RNA-seq and qRT-PCR analysis revealed that except for PgCBF6,most of
作者
刘龙博
郑树轩
郑洁
LIU Longbo;ZHENG Shuxuan;ZHENG Jie(School of Life Science,Huaibei Normal University,Huaibei Anhui 253001,China;Xiayi Branch of Henan Agricultural Radio and Television School,Shangqiu Henan 476400,China)
出处
《西北农业学报》
CAS
CSCD
北大核心
2022年第9期1154-1167,共14页
Acta Agriculturae Boreali-occidentalis Sinica
基金
安徽省高校自然科学研究项目(KJ2020A0043,KJ2021B09)
安徽省自然科学青年基金(1908085QC108)。
