中国农业科学Issue(13)：2549-2558,10.DOI:10.3864/j.issn.0578-1752.2015.13.007
玉米大斑病菌MAPK基因StIME2的基因组定位、蛋白质结构预测及表达分析
Analysis of the Genomic Location, Protein Structure Prediction and Expression of MAPK GeneStIME2 inSetosphaeria turcica
摘要
Abstract
[Objective]The objectives of this study are to determine the location in genome, investigate the protein structure of StIME2 ofSetosphaeria turcica, and to compare the expression level ofStIME2 at different developmental stages and under different stress conditions, such as temperature, oxygen stress, hyperosmolar stress, hence laying a foundation for future studying functions of StIME2.[Method] Blast search tool was used to determine the exact location ofStIME2 in genome ofS. turcica. Physical and chemical properties of StIme2 was analyzed by employing online software ProtParam, and secondary structure of StIme2 was predicted by applying Software SOMPA. Three-dimensional structure of StIme2 was doped out using PHYRE2 server and the structure model was evaluated using online software SAVES and the aim was to obtain Laplace image (Ramachandran Plot).StIME2 expression level was detected at different developmental stages and stress conditions based on semi-quantitative RT-PCR analysis.[Result]The identity ofStIME2 was 98 105, located between 1 560 184 and 1 562 574 in the positive-strand of scaffold_7 in the genome ofS. turcica. StIme2 shared characteristic conserved domains of MAPK-like protein kinase,α-helices and random coils, which were its main elements of secondary structure of StIme2.β strands were less and mainly located in N-terminal in this structure. Three-dimensional structure of the protein was composed of a smaller N-terminal and a bigger C-terminal. The expression level of StIME2 was the highest in conidium developmental periods, and was the lowest during appressorium development stage. Under different stress conditions, the expression level ofStIME2 appeared the highest when the incubation temperature was at 28℃. In hyperosmotic stress conditions, the expression level ofStIME2 increased with the increase of NaCl concentration, but the expression level of the gene was almost completely inhibited at higher stress conditions (0.8 mol·L-1 NaCl). Under oxygen stress conditions, in H2O2 stress treatment, the expression level ofStIME2 was heightened with the increase of the concentration of H2O2. And the expression level of the gene was the highest under 10 mmol·L-1 H2O2.[Conclusion]StIME2 was located between 1 560 184 and 1 562 574 in the positive-strand of scaffold_7 in the genome ofS. turcica. The characteristics of StIme2 were analyzed, and the result showed that StIme2 shared all conserved domains of MAPK kinase of plant pathogenic fungi. However, unlike three types of MAPK genes, which were widely reported in plant pathogens, StIme2 was rarely reported. The expression level ofStIME2 in conidium developmental period inS. turcica was the highest. Thus, the authors speculated thatStIME2 could play an important role in regulating the developmental processes in spore of the pathogen. Moreover, the expression level ofStIME2 changed with the temperature and the highest expression level was at 28℃. The gene may be also involved in osmotic stress and oxygen stress reaction of the pathogen.关键词
玉米大斑病菌/StIME2/生物信息学分析/基因表达Key words
Setosphaeria turcica/StIME2/bioinformatics analysis/gene expression引用本文复制引用
巩校东,王玥,张盼,范永山,谷守芹,韩建民,董金皋..玉米大斑病菌MAPK基因StIME2的基因组定位、蛋白质结构预测及表达分析[J].中国农业科学,2015,(13):2549-2558,10.基金项目
国家自然科学基金（31171805，31271997，31371897）、河北省自然科学基金（C2012204033，C2013204061）、河北省高等学校科学技术研究项目 （）
