摘要
为研究非洲菊过氧化氢酶(CAT)基因的序列特性及其在不同逆境处理下的表达水平,以‘玲珑’非洲菊为材料,利用RT-PCR技术成功克隆获得了一个编码序列(CDS)长度为1479 bp的CAT基因,对该基因及其编码蛋白进行了生物信息学分析,同时利用qRT-PCR技术研究了其在不同组织器官和不同胁迫处理下的表达水平.结果显示,CAT基因可编码492个氨基酸、分子质量为56.854 ku、等电点为6.5、无信号肽和跨膜结构的稳定亲水蛋白.其编码蛋白定位于过氧化物酶体,含有典型的CAT保守结构域和血红素结合位点.序列比对结果显示,非洲菊CAT基因与刺苞菜蓟CAT2基因的相似度最高,达88.00%,故将其命名为GjCAT2.进化分析显示,该蛋白与莴苣等菊科植物CAT的亲缘关系最近.GjCAT2基因在非洲菊花茎中的相对表达量最高,分别为叶、叶柄和花蕾的31.82、7.48和10.75倍.在聚乙二醇(PEG)模拟干旱和低温胁迫下,GjCAT2基因的相对表达量均呈“升—降—升”的趋势,分别于处理4和8 h时达到最大值;接种隐地疫霉初期,GjCAT2基因的表达受到极显著抑制,但侵染6 d时的相对表达量骤升为CK的3.11倍.本研究结果表明:GjCAT2属于典型性CAT,可能在非洲菊抵御干旱、低温以及隐地疫霉侵染过程中发挥重要作用.
In order to explore the sequence characteristics of catalase gene(CAT)in Gerbera jamesonii and its expression patterns under different stress conditions,CAT gene with 1479 bp coding sequence(CDS)was successfully cloned from‘Linglong’gerbera through RT-PCR technology for the bioinformatic analysis of its sequence and encoded protein.Furthermore,the expression patterns of CAT gene in tissues and organs under different stress treatments were analyzed by qRT-PCR.The results showed that the CAT gene encoded a stable hydrophilic protein with 492 amino acids,whose molecular weight and isoelectric point were 56.854 ku and 6.5,respectively.The CAT protein had a classical conserved domain of CAT and heme binding site but without signal peptide and transmembrane structure,and was predicted to be peroxisome-located.Sequence alignment showed highest similarity between CAT and Cynara cardunculus CAT2 up to 88.00%,therefore it was named GjCAT2.Phylogenetic analysis revealed that GjCAT2 had the closest relationship with CATs from Compositae plants,such as Lactuca sativa.qRT-PCR analysis showed the highest relative expression of GjCAT2 in inflorescence stem,which was about 31.82,7.48 and 10.75 times of that in leaf,petiole and flower bud,respectively.Under drought simulated by polyethylene glycol or low temperature stress,the relative expression of GjCAT2 showed a trend of rise-fall-rise with treatment time,and peaked at 4 and 8 h.During the early infection of Phytophthora cryptogea,the expression of GjCAT2 was significantly inhibited,but suddenly rose at 6 day,which was 3.11 times of the control.In conclusion,GjCAT2 is a typical CAT,which may play an important role in resisting drought,low temperature and P.cryptogea infection in G.jamesonii.
作者
卢珍红
武欢
焦元辰
张永艳
李绅崇
杨春梅
程春振
LU Zhenhong;WU Huan;JIAO Yuanchen;ZHANG Yongyan;LI Shenchong;YANG Chunmei;CHENG Chunzhen(Flower Research Institute,Yunnan Academy of Agricultural Sciences,Kunming,Yunnan 650100,China;Yuxi Yunxing Biotechnology Co.,Ltd.,Yuxi,Yunnan 652604,China;College of Horticulture,Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China;College of Horticulture,Shanxi Agricultural University,Jinzhong,Shanxi 030801,China)
出处
《福建农林大学学报（自然科学版）》
CSCD
北大核心
2022年第6期774-781,共8页
Journal of Fujian Agriculture and Forestry University:Natural Science Edition
基金
云南省科技厅重大科技专项计划项目(202102AE090052)
山西农业大学高层次人才科研项目(2021XG010)
福建省高原学科建设经费项目(102/71201801101)。
