Mechanism Research In Temperature Regulated Floral Induction Of Chrysanthemum

The effect of photoperiod on flower bud differentiation of chrysanthemum,a typical short-day flower,had made important progress,while the mechanism of ambient temperature regulating flower bud differentiation had rarely been reported.Therefore,in this study,we screened and obtained 4 differentially expressed genes by RNA-seq of chrysanthemum leaves under three different temperature treatments and analyzed in bioinformatics.Then the full-length sequences of CmMYB30,CmGATA12,CmGATA8 and CmWRKY53 were cloned by RT-PCR and the expression patterns were analysised by q RT-PCR.The results are as follows:1.A total of 48.33 Gb Clean Data was obtained by RNA-seq.212 014 transcripts were assembled and 100 190 unigenes were screened out.51 175 unigenes with annotated information were obtained from database annotations.2.The logarithm values of FPKM in genes expression levels of chrysanthemum samples were 10-2 and 103.The correlation among the three groups biological repetition was strong,and the reliability of RNA-seq data was high.3.Under different temperature treatments,the number of differentially expressed genes was significant,and the up-regulated differentially expressed genes were significantly more than those down-regulated.4.Four proteins coded CmGATA12?CmGATA8?CmMYB30 and CmWRKY53 were located in the nucleus.They were no transmembrane domain and belonged to acidic,unstable and hydrophilic proteins.In the secondary structure,alpha-helix and irregular curl were the main structural primitives.On the basis,the three-dimensional model were constructed.5.The open reading frame of CmMYB30 is 765 bp,encoding 254 amino acids.It has the highest homology with AaMYB30,CcMYB30-like,HaMYB306-like and LsMYB30-like.6.The open reading frame of CmGATA12 is 828 bp,encoding 275 amino acids.It has the highest homology with AaGATA,HaGATA12-like,CcGATA12-like and LsGATA9-like.7.The open reading frame of CmGATA8 is 1020 bp,encoding 339 amino acids.It has the highest homology with AaGATA,Ls GATA8-like,HaGATA8-like and CcGATA8-like.8.The open reading frame of CmWRKY53 is 531 bp,encoding 176 amino acids.It has the highest homology with AaWRKY,CcWRKY,CcWRKY53,HaWRKY53 and Ls WRKY53.9.The expression pattern of transcription factors under T1 treatment was CmGATA12-CmGATA8/CmMYB30-CmWRKY53;under T2 treatment,the expression pattern was CmGATA12/CmMYB30-CmGATA8-CmWRKY53;under T3 treatment,the expression pattern was CmGATA8-CmGATA12-CmMYB30/CmWRKY53.10.Low temperature significantly promoted the expression of CmGATA12 and CmWRKY53,and high temperature significantly promoted CmMYB30 expression at the initiation stage of flower bud differentiation.While high temperature significantly promoted the expression of CmGATA12,CmGATA8,CmMYB30 and CmWRKY53,but the regulatory reflex arc of CmWRKY53 was longer at the end of flower bud differentiation.