Expression Analysis Of PpFAR1/PpFHY3 Genes And Screening The Potential Regulator Of PpABI5 Involved In Nectarine Floral Buds During Dormancy Induction

Both light and phytohormone abscisic acid(ABA)are important signals regulating plant dormancy.FAR-RED ELONGATED HYPOCOTYL3(FHY3)and its homolog FAR-RED IMPAIRED RESPONSE1(FAR1),are involved in the regulation of seed germination induced by far red and abscisic acid,but the transcriptional changes of FHY3/FAR1 in dormancy induction process of flower bud is stillto be explored.ABI5 is a key ABA-responsive gene,so it is important to find the transcription factors that regulate the expression of ABI5 to reveal the mechanism underlying ABA signaling.The homologous genes of Arabidopsis thaliana in peach were firstly identified by NCBI blasttoolkit.At the same time the expression pattern of the five highest homology genes was characterized during the dormancy induction course,far-red light conditions and ABA-treated conditions,respectively,in floral buds of seven-year-old ‘Zhongyousihao’ nectarine(Prunus persica var.nectariana cv.‘Zhongyousihao’).The promoter region of PpABI5 were linked into pAbAi vector to construct bait vector,meanwhile the one-Hybrid cDNA library of peach was built.Then we used the cDNA and pGADT7-Rec vector to co-transform into the bait yeast strain to screen upstream transcription factors of the promoter region of PpABI5 gene via homologous recombination.The primary results are as follows:1.The expression level of Prupe.3G186100,Prupe.3G186200,Prupe.4G115100 and Prupe.3G186000 have a up-regulated tendency during the dormancy induction course,also,their transcripts are up-regulated by ABA,down-regulated by far-red light.Conversely,Prupe.2G327900 transcript is down-regulated during both the dormancy induction course and ABA-treated conditions,but up-regulated by far-red light.According to the aforementioned results,we could speculate that PpFRSs may be involved in dormancy inductionof flower bud through different methods.2.The estimated cDNA library storage capacity is almost 1×107 CFU and inserted PCR fragments sizes are about 1500 bp.Several proteins interacting with bait vector are screened out by sequencing analysis and by BLAST homology analysis,including PpDAM3,PpDAM5 and proteins of unknown function.Yeast one hybrid further confirmed that PpDAM3,PpDAM5 could bind to the promoter of PpABI5.These results indicated that PpDAM3,PpDAM5 might regulate the transcription of PpABI5 and laid a foundation for further study of signaling pathway of ABA.