百香果YUCCA基因家族鉴定与表达分析

Identification and Expressions of YUCCA Family in Passiflora edulis

【目的】黄素单加氧酶(YUCCA)基因是吲哚-3-乙酸(Indole-3-acetic acid,IAA)生物合成的主要限速酶基因之一,在植物生长发育中起着重要调控作用。本研究利用生物信息学方法对百香果(Passiflora edulis Sims.)YUCCA基因家族成员进行鉴定,以期揭示百香果YUCCA家族基因在激素响应中的功能,同时为YUCCA家族基因在其他物种中的生物信息学研究提供参考。【方法】利用生物信息学方法分析百香果YUCCA基因编码蛋白质的理化性质和保守结构域,基因的染色体定位、基因结构、系统进化树、顺式作用元件等;利用qRT-PCR探究部分成员在植物生长调节剂IAA处理下的表达情况。【结果】百香果基因组中共鉴定出29个YUCCA家族成员,不均匀分布于8条染色体,基因长度(552~9210 bp)存在明显差异,含有1~8个内含子,同时具有8个保守基序。通过系统进化树分析,发现百香果YUCCA基因家族可划分为3类,聚在同一分类中的百香果YUCCA基因具有高度的保守性,同时发现百香果的YUCCA基因与苜蓿(Medicago sativa L.)、拟南芥(Arabidopsis thaliana)亲缘关系更近,而与水稻(Oryza sativa L.)的亲缘关系较远。顺式作用元件分析显示,百香果YUCCA基因家族启动子受多种激素所诱导,可响应多种逆境胁迫。转录组数据分析结果表明:PeYUCCA6、PeYUCCA11和PeYUCCA16在台农百香果和黄金百香果叶片中呈现较低表达或者不表达,其中PeYUCCA23在台农百香果和黄金百香果的表达量最高,推测该基因对百香果叶片的发育有较大影响。qRT-PCR分析结果表明,在100μmol·L-1 IAA处理后,PeYUCCA7、PeYUCCA13、PeYUCCA17、PeYUCCA24和PeYUCCA26基因表达量显著升高。【结论】YUCCA基因家族成员在IAA处理下的表达差异较大,YUCCA基因可能在植物生长调节剂IAA处理下的百香果生长发育和抵御逆境环境过程中发挥重要作用。

【Objective】Bioinformatics of YUCCA family encoding the flavin-containing monooxygenase associated with biosynthesis of indole-3-acetic acid(IAA)in passion fruit was studied.【Methods】Bioinformatic methods were applied to analyze the physicochemical properties,conserved domains,chromosome location,structure,phylogenetic tree,and cis-acting elements of the genes in Passiflora edulis Sims.qRT-PCR was used to determine the expressions of some members under IAA treatment.【Results】There were 29 YUCCA members unevenly distributed in 8 chromosomes of P.edulis.They significantly differed in length that ranged from 552 bp to 9210 bp and contained 1–8 introns and 8 conserved motifs.A phylogenetic tree analysis divided the family into three distinct categories,and within a same class the members were highly conservative.Genetically,the genes were more closely related to Medicago sativa L.and Arabidopsis thaliana than Oryza sativa L.The cis-acting element analysis indicated that the promoter of the family genes could be induced by various hormones and respond to various stresses.PeYUCCA6,PeYUCCA11,and PeYUCCA16 showed low or no expression in the leaves of Tainong and Golden Passion Fruit,but PeYUCCA23 had a high expression suggesting its predominant role in the plant development.The treatment of 100μmol·L-1 IAA significantly elevated the expressions of PeYUCCA7,PeYUCCA13,PeYUCCA17,PeYUCCA24,and PeYUCCA26.【Conclusion】The expressions of YUCCAs in P.edulis varied greatly under IAA treatment.But as a family,the genes likely played an important role in the growth,development,and resistance to adverse environment of passion fruits.