红皮红肉和红皮白肉火龙果果肉呈色相关基因差异表达分析  

Differential Expression Analysis of Genes Related to Flesh Color in Hylocereu polyrhizus and Hylocereu undatus

作　　者：郭攀阳 曾灿彬 刘成立 韦双双[1] 黄家权[1] 汤华[1] Guo Panyang;Zeng Canbin;Liu Chengli;Wei Shuangshuang;Huang Jiaquan;Tang Hua(Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources,College of Tropical Crops,Hainan University,Haikou,570228)

机构地区：[1]海南大学热带作物学院,海南热带生物资源可持续利用国家重点实验室培育基地,海口570228

出　　处：《分子植物育种》2021年第13期4311-4326,共16页Molecular Plant Breeding

基　　金：国家火龙果良种联合攻关项目(HD-KYH-2019042);2019年海南省研究生创新科研课题(Hys2019-138);农业农村部“火龙果种质资源保护及种质创新”项目(18200032-1)共同资助。

摘　　要：火龙果为热带新兴水果,常见的有红皮红肉和红皮白肉两种类型。为探究这两种火龙果果色差异原因,发掘差异表达基因(differencially expressed genes,DEGs),本研究分别在青果期(授粉后第15天)和成熟期(授粉后35 d)采集红皮红肉火龙果(Hylocereu polyrhizus)和红皮白肉火龙果(Hylocereu undatus)的果肉样品,进行转录组测序。获得高质量序列共53240条。通过对DEGs进行分析,发现火龙果在同一品种不同时期间的差异比同一时期不同品种间的更大。分别在R1 vs R3和W3 vs R3两组进行GO功能富集分析和KEGG代谢通路分析,通过GO分析发现,在分子功能上,有部分基因显著富集在蛋白与转录因子结合活动上;通过KEGG分析,大部分基因富集在次生代谢产物合成通路、氨基酸和核酸代谢通路、酪氨酸代谢通路上,其中酪氨酸是甜菜色素合成的前体。综上所述,红皮红肉火龙果发育过程中伴随着大量甜菜色素的合成,酪氨酸作为前体在其中起关键作用,且该色素的合成需要大量氨基酸、酶及转录因子的参与。甜菜色素合成途径中的分子调控机制尚未明确,通过本研究可以发掘火龙果中甜菜色素合成相关的关键基因,是开展后续实验的基础,为甜菜色素代谢途径的完善提供了有用的信息。Pitaya is a burgeoningly tropical fruit.There are two common varieties,red peel with red pulp and red peel with white pulp.To investigate the reason for different colors in two kinds of pitaya,we explore differentially expressed genes(DEGs).In this study,we profiled transcriptome in flesh of two varieties(Hylocereu polyrhizus and Hylocereu undatus)in green stage and mature stage respectively.53240 reads with high quality were obtained.Analysing the DEGs,we found there were bigger differences in different stages rather than different varieties.Gene ontology(GO)functional analysis and KEGG pathway analysis were adopted in R1 vs R3 and W3 vs W3.Through GO analysis,we found many genes enriched in protein binding transcription factor activity in molecule function.Through KEGG pathway analysis,we found most genes were enriched in biosynthesis of secondary metabolism,amino acid and nucleic acid metabolism,and tyrosine metabolism.In addition,tyrosine was the precursor of betalaines.In conclusion,the development of Hylocereu polyrhizus accompanied by the synthesis of a large amount of betalaines,tyrosine played a key role as a precursor,and the synthesis of this pigment required a mass of amino acids,enzymes,and transcription factors.The molecular regulation mechanism of betalaines synthesis pathway has not cleared yet.This study explored key genes related to betalaines synthesis and provided useful information for optimizing the betalaines synthesis pathway,which was the basis of later experiments.

关 键 词：火龙果果肉颜色发育 转录组测序 差异表达基因 甜菜色素 

分 类 号：S667.9[农业科学—果树学]