PhePEBP Family Genes Regulated By Plant Hormones And Drought Are Associated With The Activation Of Lateral Buds In Phyllostachys Edulis

Bamboo(Phyllostachys edulis)belongs to Bambusoideae of Graminaceae,which is a commercially important plant and is widely used.It produces offspring both sexually and asexually.The latter way dominates its propagation and reflects in the development of dormant buds,which remain in undifferentiated status and develop into the awakening buds upon the activation of underground rhizome.Lately they turn into new shoots after undergoing a ‘fast stem growth' phase.However,only5-8% of the lateral buds can eventually develop into new bamboo.Therefore,it is of great significance to explore the development process of bamboo shoots.In this experiment,the characteristics of PEBP gene family and its dynamic expression patterns in the process of lateral buds were systematically analyzed.The results are as following:1.Twenty-five PhePEBP family proteins were identified in the bamboo,including 16 PheFT,8PheTFL and 1 PheMFT.Twenty-four genes contain typical four exons and three introns,with the exception of PheFT10 gene(containing six exons and five introns).PheFT10 underwent alternative splicing and produced at least four transcription(PheFT10?,PheFT10?,PheFT10?and PheFT10?).2.Twenty-four genes were expressed at low level,with the exception of PheTFL4 gene and showed significant tissue-specific.3.qRT-PCR results showed that the expression of 72%(18/25)of PhePEBP genes were inhibited by drought,and the inhibition of PheTFL family by drought stress was more obvious than that of PheFT family.Under drought stress,transcription PheFT10? significantly increased expression,PheFT10?significantly reduced expression,and PheFT10? expression showed no significant change,indicating that PheFT10? transcription was playing an important role under drought stress compared with PheFT10? and PheFT10?.4.qRT-PCR the results showed that the expression of PhePEBP genes were affected by hormones.Compared to the control,the transcription levels of eighteen genes at all points in time were increased after GA treatment,however,the transcription levels of PheFT12 and PheFT16 decreased at all points in time.In ABA treatment,eighteen gene expression increases,with the exception of PheFT6 and PheFT15,these two genes were found at all points in time to be reduced expression.In JA treatment,it was found that the transcription levels of twenty genes at all points in time were raised,however,only the transcription levels of PheFT6 at all points in time were lowered.Overall,ABA had a greater impact on the expression level of the PhePEBP genes than GA and JA.Five PhePEBP family genes are mediated by ABA,GA and JA hormones;three PhePEBP genes were regulated by GA and ABA hormones,one PhePEBP Genes was regulated by GA and JA hormones,and four PhePEBP family genes were regulated by ABA and JA hormones.5.The expression of PhePEBP genes in different sizes of lateral buds was detected,and the results showed that the expression of twenty-one PhePEBP genes increased significantly from dormant buds to bud germination period.Combined with the data of conservative amino acid residues in the PEBP family,the PheFT9,PheTFL2 and PheTFL8 genes in bamboo were related to lateral buds development.Above all,the results suggested that the expression of PhePEBP family genes were up-regulated by plant hormones and down-regulated by drought.PhePEBP family genes might be involved in the activation of lateral buds.These findings open the door for in-depth exploring the biological function of the PhePEBP family genes regulating the activation of dormant bud in moso bamboo.