摘要
磷酸烯醇式丙酮酸羧化酶是(phosphoenolpyruvate carboxylase, PEPC)是C_4光合途径的关键酶之一。为了解籽粒苋PEPC基因密码子的使用特性,运用CHIP、CUSP、CodonW和SPSS软件分析籽粒苋PEPC基因密码子的偏好性,并分别与其他24种物种PEPC以及模式生物基因组进行比较。结果显示,籽粒苋PEPC基因偏好使用A/T结尾的密码子,26种偏好密码子(RSCU>1)中偏好性较强的有GCT、CTC和GTG (RSCU较强)。与其他物种同源基因相比,密码子选择偏性存在差异。进化树分析表明,基于PEPC基因编码序列聚类结果比密码子使用偏性分类结果能更准确地反映物种间的亲缘关系;密码子使用频率比较结果发现,酵母真核表达系统更适用于籽粒苋PEPC基因异源表达实验,而籽粒苋PEPC基因与模式植物基因组之间密码子使用偏性差异较小,尤其番茄可能为该基因转基因研究最为理想的受体。本研究为籽粒苋PEPC基因在作物高光效基因工程中选择最佳的外源表达系统以及提高其表达水平提供了前期的研究基础。
Phosphoenolpyruvate carboxylase （PEPC） is one of the key enzymes in the photosynthetic pathway of C4. To understand the codon usage features ofPEPC gene in Amaranthus hypochondricleus, the sequence of PEPC gene of A maranthus hypochondriacus was analyzed by using bioinformatics soffwares including CHIP, CUSP, CodonW and SPSS, and it was also compared with PEPC genes from 24 plant species and genomes of model organisms. The results showed that the A maranthus hypochondriacus PEPC preferred to use codons ended with A or T. There were 26 biased codons （relative synonymous codon usage, RSCU〉 1）, among which GCT, CTC and GTG （stronger RSCU） were highly frequently used codons. Codon selection bias was different from the homologous genes of other species. The phylogenetic tree analysis indicated that PEPC based CDS could reveal the evolutionary relationship among different species much better than the result analyzed by RSCU. According to codon usage frequency, the yeast expression system was more suitable for heterologous expression of PEPC, and the difference of codon bias between of PEPC gene in A maranthus hypochondriacus and model plant genomes was not significant. Particularly, Solarium lycopersicum might be the best receptor for transgenosis of this gene. The study might provide the basis for the previous studies about selecting appropriate expression systems and improving the expression level of PEPC from A maranthus hypochondriacus by high-photosynthesis gene engineering.
作者
冯瑞云
闫建俊
侯雅静
雷梦林
郝雅萍
王慧杰
白云凤
Feng Ruiyun;Yan Jianjun;Hou Yajing;Lei Menglin;Hao Yaping;Wang Huijie;Bai Yunfeng(Key Laboratory of Crop Genetics and Molecular Improvement of Shanxi Province,Institute of Crop Sciences,Shanxi Academy of Agricultural Sci-ences,Taiyuan,030031;China Key Laboratory of Loess Plateau Crop Gene Resources and Germplasm Creation,Ministry of Agriculture,Institute of Crop Germplasm Resources,Shanxi Academy of Agricultural Sciences,Taiyuan,030031)
出处
《分子植物育种》
CAS
CSCD
北大核心
2018年第20期6646-6656,共11页
Molecular Plant Breeding
基金
由山西省主要农作物种质创新与分子育种山西省重点科技创新平台(201605D151002)
山西省自然科学基金项目(201601D011075)
山西省青年科技研究基金项目(201701D221210)共同资助
关键词
籽粒苋
PEPC基因
密码子偏好性
聚类分析
A maranthus hypochondriaeus
PEPC gene
Codon usage bias
Cluster analysis
