微藻单针藻KCS基因家族生物信息学分析

Identification and Analysis of the KCS Gene Family in Microalgae Monoraphidium neglectum

酮脂酰CoA合成酶(3-ketoacyl-CoA synthase,KCS)是生物体内超长链脂肪酸(very-long-chain fatty acids,VLCFAs)合成的关键限速酶,决定了VLCFAs的合成速率和碳链长度。单针藻(Monoraphidium)是微藻能源热门的研究对象,为了进一步探究其KCS基因家族的生理特征,揭示单针藻超长链脂肪酸的合成机制。我们利用单针藻基因组信息,对单针藻KCS基因家族进行生物信息学分析。单针藻KCS基因家族共含有26个基因,蛋白质的氨基酸序列长度在58~1306 aa之间。KCS基因家族存在三种保守结构域,分别为:FAE1_CUT1_RppA结构域、Chal_sti_synt_C结构域、Chal_sti_synt_N结构域。根据系统发育树结果,单针藻KCS基因家族可以分为四个亚族。亚族内的基因结构(外显子分布,保守结构域,保守基序)相似,而亚族之间的基因结构存在差异。不同物种KCS比较结果发现亲缘性较近的物种间,基因家族的相似度较高,表明基因结构的保守性。而单针藻基因家族中存在不同亚族,说明物种在进化过程中对外界多变环境的适应。单针藻作为微藻能源的热门研究对象,研究KCS基因家族能进一步发掘单针藻的基因功能,加深对其脂肪酸合成延长机制的了解,为利用分子手段提高单针藻的抗性和品质特性提供参考;同时有利于系统研究植物KCS基因的进化情况,揭示KCS蛋白在植物生理调控中的作用和地位。

3-ketoacyl-CoA synthase(KCS)is a key limiting enzyme in the synthesis of VLCFAs,which determines the synthesis rate and carbon chain length of VLCFAs.In order to further explore the physiological characteristics of KCS gene family and VLCFAs synthesis mechanism of Monoraphidium,we did the bioinformatics analysis of itself KCS gene family based on the Monoraphidium genome.The KCS gene family of Monoraphidium mainly contained 26 genes,and the amino acid sequence length of protein ranged from 58 aa to 1306 aa.KCS gene of Monoraphidium has three relatively conserved structure,including FAE1_CUT1_RppA domain,Chal_sti_synt_C domain,Chal_sti_synt_N domain.According to the phylogenetic tree results,the KCS gene family of Monoraphi-%dium can be divided into four subtribe.The KCS gene structure(exon distribution,conserved domain,conserved motif)was similar withinsubtribe,but was different between the subtribe.The comparison of KCS gene among different species showed that the similarity of gene family was relatively high among the species with close affinity,indicating the gene conservation.Meanwhile,the presence of different subgroups in the KCS gene family of Mono-%raphidium,indicated that the adaptation of different species to changeable environment during evolution.As the hot research object of microalgae energy,analysis of the KCS gene family in Monoraphidium provides insight:further explore the KCS gene family function,synthesis and prolonged of fatty acid metabolism,which provides a reference in improving the resistance and quality of Monoraphidium by molecular methods and be beneficial to study the evolution of plant KCS gene family and reveal the role of KCS protein in plant physiological regulation.