| Leaf is the main photosynthetic organ in plants.Mature leaf is composed of leaf blade and petiole.The petiole physically supports the leaf blade to get enough light.Hence,the regulation of petiole development plays a significant role in photosynthesis.Petiole elongation is a complex process which is affected by transcription factors,ncRNAs and so on.And it is also regulated by endogenous hormones such as Brassinosteroids(BRs)and environment such as temperature.The molecular mechanism of petiole development makes great progress in promoting plant photosynthetic efficiency,breeding high photosynthetic efficiency varieties,and increasing crop yield using petiole as the main edible organs.In this study,the whole transcriptome of the leaf and petiole of PHL was sequenced.The main results are as follows:1.Whole transcriptome sequencing results show that,10646 mRNAs(8333 mRNAs were significantly up-regulated and 2313 mRNAs are significantly down-regulated in petiole),7 circRNAs(3 circRNAs are significantly up-regulated and 4 circRNAs are significantly downregulated in petiole),303 IncRNAs(130 lncRNAs are significantly up-regulated and 173 lncRNAs are significantly down-regulated in petiole),195 miRNAs(77 significantly miRNAs are up-regulated and 118 miRNAs are significantly down-regulated in petiole)are identified.Then,24 genes were selected randomly for qRT-PCR verification.Subsequently,the ceRNA regulatory network associated with petiole development was established.2.Four petiole-enriched genes were selected from the transcriptome,they were BraA03g031670.3C,BraA05g042610.3C,BraA02g040480.3C coding ALOG family,and Bra07g027780.3C coding for bZIP transcription factor named pdr1(petiole developmentrelated gene 1),pdr2,pdr3,pdr4.The fusion expression vectors of pBWA(V)HS1-3-GLosgfp,pBWA(V)HS2-2-GLosgfp,pBWA(V)HS6-3-GLosgfp and pBWA(V)HS4-5-GLosgfp were constructed.The results showed that four genes were expressed in the cell nucleus,and the signals were good.3.We identified the functions of pdr1,pdr2,pdr3,pdr4.Agrobacterium bacterials with the pBWA(V)HS1-3-GLosgfp,PBWA(V)HS2-2-GLosgfp,PBWA(V)HS4-5-GLosgfp,PBWA(V)HS6-3-GLosgfp were used to infect Arabidopsis thaliana and tobacco with the method of dipping flower.The positive seedlings were obtained and screened to T3 generation by using resistant medium with hygromycin and PCR identification except pdr4.The results show that the positive seedlings of pdrl,pdr3 don’t have significant difference compared with wild type.The growth of leaves and petioles of pdr2 and pdr4 was inhibited obviously. |
