不结球白菜β-1,3-葡聚糖酶基因cDNA全长的克隆与表达分析  

Cloning and Characterization of A full-length cDNA of β-1,3-glucanas Gene in Brassica campestris ssp.chinensis

作　　者：王彦华[1] 侯喜林[1] 申书兴[2] 

机构地区：[1]南京农业大学作物遗传与种质创新国家重点实验室,南京210095 [2]河北农业大学园艺学院,保定071001

出　　处：《农业生物技术学报》2006年第6期917-921,共5页Journal of Agricultural Biotechnology

基　　金：高等学校博士点科研基金(No.20030307021)资助。

摘　　要：以不结球白菜(Brassicacampestrisssp.chinensis)抗病自交系雪克青为实验材料,通过RACE技术,获得了不结球白菜β-1,3-葡聚糖酶基因的cDNA全长序列。序列分析发现,该基因全长1275bp,编码363个氨基酸,分子量40.66kD,等电点(pI)9.27。推导的氨基酸序列与芜菁bg1基因具有96%的同源性,与拟南芥bg2基因具有61%的同源性,与其它植物β-1,3-葡聚糖酶基因的同源性为49%￣57%。将该序列提交GenBank,登录号为AY836001。Southern杂交显示该基因在不结球白菜基因组中的拷贝数多于1个。半定量RT-PCR分析表明,该基因有低水平的组成型表达,在霜霉病菌(Peronosporaparasitica)诱导后24h其表达量达到高峰。Using RACE technic, the full-length cDNA of beta-1,3-glucanase gene was cloned from Brassica carapestris ssp. chinensis cultivar Xuekeqing ,which displayed resistance to downy mildew in field. Sequence analysis indicated that cloned Bcbg2 gene consisted of 1 275 nucleotides encoding a 40.66 kD peptide containing 363 amino acids with pI of 9.27. Further comparison to turnip beta-1,3-glucanase（bgl） gene and Arabidopsis thaliana beta-1,3-glucanase（bg2） gene showed the identity was 96% and 61%, respectively, and the similarity to beta-1,3-glucanase genes in other plants was from 49% to 57%. The sequence has been submitted to the GenBank database and the accession number is AY836001. Southern blotting analysis indicated that there was more than one copy of Bcbg2 gene in B. campestris ssp.chinensis genome. Semi- quantitative RT-PCR analysis revealed the gene was constitutively expressed with lower level, and the corresponding mRNA was accumulated most abundantly 24 h after infected by Peronospora parasitica.

关 键 词：不结球白菜 霜霉病 β-1 3-葡聚糖酶基因 RACE 半定量RT-PCR 

分 类 号：S188[农业科学—农业基础科学]