忽地笑LaSUVH1基因克隆与功能分析  

Cloning and Functional Analysis of LaSUVH1 Gene from Lycoris aurea

作　　者：徐君雅 蔡黎丽 孙彬 江玉梅[1] 徐晟[1] 汪仁[1] XU Junya;CAI Lili;SUN Bin;JIANG Yumei;XU Sheng;WANG Ren(Institute of Botany, Jiangsu Province and Chinese Academy of Sciences , Nanjing 210014, China)

机构地区：[1]江苏省中国科学院植物研究所[南京中山植物园],南京210014

出　　处：《西北植物学报》2020年第11期1807-1815,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(31770387,81603240);江苏省“六大人才高峰”高层次人才培养项目(NY-081);江苏省省属公益类科研院所自主科研项目(BM2018021-5)。

摘　　要：为了深入探究忽地笑(Lycoris aurea)组蛋白赖氨酸甲基转移酶(histone lysine methyltransferase,HKMT)基因的功能,该研究根据前期转录组测序结果,采用RT-PCR方法克隆得到一个组蛋白赖氨酸甲基转移酶基因LaSUVH1。序列分结果表明,LaSUVH1基因的编码区(coding sequences,CDs)序列长2007 bp,编码668个氨基酸残基;LaSUVH1蛋白不具有信号肽结构,无跨膜结构,为亲水性蛋白,含有SET、YDG/SRA、Pre-SET和Post-SET结构域;序列比对和系统进化树分析发现,LaSUVH1与芦笋AoSUVH1-like蛋白亲缘关系最近。实时荧光定量PCR分析表明,LaSUVH1基因在忽地笑不同组织部位均有表达,且在叶中表达量最高。经潮霉素筛选成功获得3个反义过表达LaSUVH1的转基因拟南芥株系。进一步功能分析发现,反义过表达LaSUVH1促进了拟南芥幼苗侧根的发生,降低了拟南芥对NaCl的耐受性,增加了拟南芥种子萌发对脱落酸(ABA)的敏感性,表明LaSUVH1基因响应盐胁迫应答可能依赖ABA信号通路。In order to explore the functions of histone lysine methyltransferase(HKMT)gene in Lycoris aurea,we cloned a histone lysine methyltransferase gene LaSUVH1 using the RT-PCR method based on previous transcriptome sequencing data.The coding sequences(CDs)of LaSUVH1 gene is 2007 bp in length,encoding a deduced polypeptide of 668 amino acids.LaSUVH1 is a stable hydrophilic protein without signal peptide,and had no transmembrane structure.It had SET{Suppressor of Variegation 3-9[SU(VAR)3-9],Enhancer of Zeste[E(Z)],and Trithorax(TRX)},YDG(named for three conserved amino acids)/SRA(SET and RING finger-associated),Pre-SET,and Post-SET conserved domains.Multiple sequence alignment and phylogenetic tree analysis showed that the deduced protein LaSUVH1 shares higher identity with Asparagus officinalis AoSUVH1-like protein.Additionally,quantitative real-time PCR(qRT-PCR)analysis indicated that LaSUVH1 was ubiquitously expressed in different tissues,and had the highest expression level in leaf.By hygromycin screening,three transgenic Arabidopsis thaliana lines with antisense-overexpression of LaSUVH1 gene were obtained.Further functional analysis showed that antisense-overexpression of LaSUVH1 gene promoted lateral root formation,reduced the tolerance to NaCl stress and increased the sensitivity of seed germination to abscisic acid(ABA)in Arabidopsis,suggesting LaSUVH1 functioning in salt stress response might be involved in ABA-dependent signaling pathway.

关 键 词：忽地笑 SUVH基因 组蛋白赖氨酸甲基转移酶 功能分析 

分 类 号：Q785[生物学—分子生物学] Q786