特异lncRNAs在乙烯诱导的香蕉果实成熟中的作用及其机制研究

Banana is one of the most important crops in tropical and subtropical countries with a high nutritional value for human health. Ethylene plays important roles in regulation of ripening process and fruit quality formation, which initiates banana ripening process. Long non-coding RNAs (lncRNAs) has been reported to be a vital component of eukaryotic gene regulation, and play an important role in the regulation of fruit ripening. In the preliminary work, we have finished lncRNAs sequecing and have investigated specific lncRNAs involved in ethylene-induced banana fruit ripening by using banana whole genome information analysis. In this work, we will endeavor to elucidate function and mechanisms of the specific lncRNAs involved in ethylene-induced banana fruit ripening by VIGS, over-expressing and transcriptomics analysis. These attempts and possible findings will provide enormous data to understand complex network of the lncRNAs during fruit ripening. It will lay the foundation for regulation of banana fruit ripening, quality improvement and the breeding of banana varieties.

香蕉是重要的热带和亚热带果树之一，其果实香甜味美，营养丰富。作为典型的呼吸跃变型果实，香蕉果实的成熟受乙烯诱导，因此研究乙烯诱导的果实成熟进程对香蕉品质改良与贮藏运输具有重要的作用。长链非编码RNAs（long non-coding RNAs, lncRNAs）已被证实在真核生物基因表达调控中起着至关重要的作用，与果实的成熟调控密切相关。本项目在已完成lncRNAs测序的基础上，利用香蕉全基因组注释，借助信息学分析手段，筛选并鉴别乙烯诱导的香蕉果实成熟过程中特异lncRNAs，预测其对应靶基因，同时应用VIGS技术和转基因过表达技术、转录组学分析，揭示乙烯诱导的香蕉成熟进程中特异lncRNAs的功能及其作用机制，为香蕉品种改良与果实成熟调控奠定基础。

香蕉是重要的热带和亚热带果树之一，其果实香甜味美，营养丰富。作为典型的呼吸跃变型果实，香蕉果实的成熟受乙烯诱导，因此研究乙烯诱导的果实成熟进程对香蕉品质改良与贮藏运输具有重要的作用。长链非编码RNAs（long non-coding RNAs, lncRNAs）已被证实在真核生物基因表达调控中起着至关重要的作用，与果实的成熟调控切相关。本项目利用高通量测序，在香蕉果实中鉴定获得了11268个lncRNA，主要涉及代谢途径，与乙烯调控香蕉果实成熟相关的lncRNA有343个，反式作用所对应的靶基因数量最多，是主要的作用模式。将54个差异lncRNA进行qPCR验证，结果显示与高通量测序结果一致。挑选了2个在果实中特异表达的lncRNA和其对应的靶基因进行了超表达载体和沉默载体构建，采用农杆菌介导的横切薄片法转化香蕉，在香蕉中进行了功能验证，获得了转基因再生植株。从转录和代谢层面分析了香蕉在果肉、果皮上基因表达和代谢物积累差异。在果肉和果皮中分别检测到3977个和3282个基因有表达差异，与乙烯合成相关的基因有25个。开展了香蕉广泛靶向代谢组测序，在果皮和果肉中共检测到了426个代谢产物，在果肉中差异表达的有39个，果皮中差异表达的有45个，涉及91个代谢通路。这些研究为香蕉品种改良与果实成熟调控奠定了基础。