雨生红球藻磷脂-二酰甘油酰基转移酶基因的鉴定与表达分析  

Identification and Expression Analysis of Phospholipid-Diacylglycerol Acyltransferase Gene(HpPDAT)from Haematococcus pluvialis

作　　者：赵春超 张宏江 臧敦秀 崔红利 李润植 ZHAO Chunchao;ZHANG Hongjiang;ZANG Dunxiu;CUI Hongli;LI Runzhi(Institute of Molecular Agriculture and Bioenergy,College of Agriculture,Shanxi Agricultural University,Taigu 030801,China)

机构地区：[1]山西农业大学农学院/分子农业与生物能源研究所,山西太谷030801

出　　处：《山西农业科学》2022年第3期319-326,共8页Journal of Shanxi Agricultural Sciences

基　　金：国家自然科学基金项目(31902394);山西农谷建设科研专项项目(SXNGISKYZX201906);山西农业大学博士启动基金项目(2018YJ16)。

摘　　要：单细胞光自养雨生红球藻富集虾青素(AST)和三酰甘油(TAG)的合成调控机制目前还未得到解析。以雨生红球藻-797株系为试验材料,克隆编码磷脂-二酰甘油酰基转移酶(HpPDAT)的基因、鉴定酶蛋白理化特征和分析不同光质下的表达谱。结果显示,基于雨生红球藻转录组数据,鉴定获得一条编码HpPDAT的cDNA序列,全长3138 bp,编码978个氨基酸,蛋白的分子式为C_(4437)H_(6997)O_(1396)N_(1289)S_(38),分子质量为101.95 ku,理论等电点为6.15。多序列比对结果显示,HpPDAT具有LCAT家族典型保守域。系统发育分析显示,HpPDAT与微藻中的PDATs亲缘关系较近,而与高等植物的PDATs亲缘关系较远。不同光质(白光、高白光、高蓝光、紫外和白光+紫外)条件下HpPDAT基因的表达谱分析揭示,与黑暗条件下的藻细胞相比,所测光质条件下藻细胞HpPDAT基因的表达均上调,特别是高蓝光(10000 lx)显著促进了HpPDAT基因的表达,表达量达到黑暗条件下的9.6倍;不同光质条件下的细胞脂质合成发现,光照处理的总脂积累量要明显高于黑暗处理。HpPDAT的表达量与总脂的积累量呈现出一致性,在高蓝光处理下获得了最高的总脂积累量(27%),是黑暗处理的1.9倍。Single-celled photoautotrophic green algal Haematococcus pluvialis enriches astaxanthin(AST)and triacylglycerol(TAG).However,its synthesis regulation mechanism has not yet been resolved.In this paper,the gene encoding phospholipid diacylglycerol acyltransferase(HpPDAT)was cloned from the H.pluvialis-797 strain.Meanwhile,the protein physicochemical characteristics of the enzyme was identified.In addition,the transcription expression profiles of HpPDAT under different light quality conditions were also determined.A full-length cDNA encoding HpPDAT was identified based on the transcriptome data of H.pluvialis.It contained 3138 bp and encoded 978 amino acids residues.The molecular formula,molecular weight,and theoretical isoelectric point were C_(4437)H_(6997)O_(1396)N_(1289)S_(38),101.95 ku,and 6.15,respectively.Multiple sequence alignment showed that HpPDAT had typical conserved domains of the LCAT family.Phylogenetic analysis indicated that HpPDAT was closely related to PDATs from microalgae,but was relatively distantly related to PDATs from higher plants.Analysis the HpPDAT gene expression profiles under different light quality conditions(white light,high white light,high blue light,ultraviolet and white light+ultraviolet)revealed that compared with algae cells under dark conditions,the expressions of HpPDAT gene in algae cells under the measured light quality conditions were all up-regulated.In particular,high blue light(10000 lx)significantly promoted the expression of HpPDAT gene,the expression quantity under the light reached 9.6 times of that under dark conditions.Meanwhile,analysis lipid synthesis under different light quality conditions found that the accumulation of total lipids under light treatment was significantly higher than that under dark treatment.The expression quantity of PDAT is consistent with the accumulation of total lipids.The highest accumulation of total lipids(27%)was obtained under high blue light treatment,the accumulation was 1.9 times of that under dark treatment.

关 键 词：磷脂-二酰甘油酰基转移酶 基因鉴定 表达 光诱导 雨生红球藻 

分 类 号：S949.29[农业科学—水产养殖]