红肉火龙果(Hylocereus polyrhizus)果实与茎转录组测序分析

Transcriptome Sequencing Analysis of the Fruit and Stem from the Redflesh Pitaya(Hylocereus polyrhizus)

为探讨红肉火龙果果实和茎转录组模式及可溶性糖和甜菜苷色素积累的分子基础,采用Illumina HiSeq 4000技术对果实果肉和茎进行转录组测序。共获得28.81 Gb的Clean read,组装获得79 658个Unigene(54.98 Mb),平均长度为690 bp。35 139个Unigene能够在NR、NT、Swiss-Prot、KEGG、COG、PFAM和GO数据库中注释。大量Unigene参与多条代谢途径,包括碳水化合物和氨基酸代谢、次生代谢、柠檬酸循环、果糖和甘露糖代谢等。在果实果肉中上调表达的Unigene主要参与淀粉、蔗糖代谢途径和谷胱甘肽代谢,在茎中上调表达的Unigene主要参与碳代谢和光合作用代谢。筛选获得5个与果实可溶性糖和甜菜苷色素积累的重要候选Unigene。本研究结果克隆的火龙果果实可溶性糖和甜菜苷色素积累相关功能基因,对探讨基因的生理功能和调控机制,改良火龙果果实品质提供重要基础。

In order to investi gate transcriptional patterns of the fruit and stem, and molecular basis of soluble sugar and betanin pigment accumulation, the fruit flesh and stem were sequenced the transcriptome using Illumina Hi Seq 4000 technique. A total of 28.81 Gb of clean read was obtained, and 79 658 unigene(54.98 Mb) were generated with an average length of 690 bp. 35 139 unigene could be annotated on NR, NT, Swiss-Prot, KEGG,COG, PFAM and GO databases. A large number of unigene were involved in multiple metabolic pathways,including carbohydrate and amino acid metabolism, secondary metabolism, citric acid cycle, fructose and mannose metabolism. The up-regulated expression of unigenes in fruit fresh mainly involved in starch, sucrose metabolic pathways and glutathione metabolism, and the up-regulated expression of unigenes in stem mainly involved in carbon metabolism and photosynthetic metabolism. Five candidate functional unigenes involved in soluble sugar and betanin pigments accumulation in fruits were obtained by screening. The result of this study might provide an important basis for cloning functional genes related to the soluble sugar and betanin pigments accumulation in pitaya fruits, exploring the physiological function and regulation mechanism of genes, and improving fruit quality.