Comparative transcriptome analysis revealing the potential mechanism of seed germination stimulated by exogenous gibberellin in Fraxinus hupehensis

BMC Plant Biology

Zexiong Chen¹  Shuiyuan Cheng²  Weiwei Zhang³  Qiling Song³  Yongling Liao³  Gongping Nie³  Mingqin Zhou³  Jian Zhang³  Jiabao Ye³  Feng Xu⁴ 

[1] 0000 0004 1761 2871, grid.449955.0, Research Institute for Special Plants, Chongqing University of Arts and Sciences, 402160, Chongqing, China;0000 0004 1798 1968, grid.412969.1, National R&D for Se-rich Agricultural Products Processing Technology, Wuhan Polytechnic University, 430023, Wuhan, China;grid.410654.2, College of Horticulture and Gardening, Yangtze University, 434025, Jingzhou, Hubei, China;grid.410654.2, College of Horticulture and Gardening, Yangtze University, 434025, Jingzhou, Hubei, China;grid.410654.2, Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, 434025, Jingzhou, Hubei, China;

关键词: Fraxinus hupehensis;    Seed germination;    Transcriptome;    Germination;    Exogenous gibberellin;    Differentially expressed genes;   

DOI  :  10.1186/s12870-019-1801-3

来源: publisher

【 摘 要 】

BackgroundFraxinus hupehensis is an endangered tree species that is endemic to in China; the species has very high commercial value because of its intricate shape and potential to improve and protect the environment. Its seeds show very low germination rates in natural conditions. Preliminary experiments indicated that gibberellin (GA3) effectively stimulated the seed germination of F. hupehensis. However, little is known about the physiological and molecular mechanisms underlying the effect of GA3 on F. hupehensis seed germination.ResultsWe compared dormant seeds (CK group) and germinated seeds after treatment with water (W group) and GA3 (G group) in terms of seed vigor and several other physiological indicators related to germination, hormone content, and transcriptomics. Results showed that GA3 treatment increases seed vigor, energy requirements, and trans-Zetain (ZT) and GA3 contents but decreases sugar and abscisic acid (ABA) contents. A total of 116,932 unigenes were obtained from F. hupehensis transcriptome. RNA-seq analysis identified 31,856, 33,188 and 2056 differentially expressed genes (DEGs) between the W and CK groups, the G and CK groups, and the G and W groups, respectively. Up-regulation of eight selected DEGs of the glycolytic pathway accelerated the oxidative decomposition of sugar to release energy for germination. Up-regulated genes involved in ZT (two genes) and GA3 (one gene) biosynthesis, ABA degradation pathway (one gene), and ABA signal transduction (two genes) may contribute to seed germination. Two down-regulated genes associated with GA3 signal transduction were also observed in the G group. GA3-regulated genes may alter hormone levels to facilitate germination. Candidate transcription factors played important roles in GA3-promoted F. hupehensis seed germination, and Quantitative Real-time PCR (qRT-PCR) analysis verified the expression patterns of these genes.ConclusionExogenous GA3 increased the germination rate, vigor, and water absorption rate of F. hupehensis seeds. Our results provide novel insights into the transcriptional regulation mechanism of effect of exogenous GA3 on F. hupehensis seed germination. The transcriptome data generated in this study may be used for further molecular research on this unique species.

【 授权许可】

CC BY