Bioinformatics Identification And Expression Analysis Of Cell Cycle Regulatory Factors During Expansion Of Zizania Latifolia

In Arabidopsis thaliana and rice,the researches on the cell cycle regulation mechanism of Zizania latifolia have been extensive,but the researches on the cell cycle regulation mechanism of Zizania latifolia have been few.In this paper,the cell cycle regulation factors of Zizania latifolia have been screened out through the whole-genome identification of the cell cycle regulatory factors of Zizania latifolia.Including Cyclin,Cyclin dependent kinase(CDK),Cyclin dependent kinase inhibitor(CKI/KRP),E2 F transcription factors,etc.The phylogenetic tree was constructed by multiple sequence alignment of cyclins in Zizania latifolia,Arabidopsis thaliana,rice,maize and tomato by bioinformatics method.Then the conserved motif of cell cycle regulation factors and the exon and intron structure of genes were analyzed.The auxin can control the bulge of Zizania latifolia by regulating the cell cycle.By spraying auxin exogenously,the fertility rate and the number of giral formation of Zizania latifolia were observed,which proved that auxin was the key factor of bulge of Zizania latifolia.The transcriptome sequencing was performed on shoot tips of Zizania latifolia.sinensis at 0 h,2 h,8 h and 24 h after the application of auxin and cytokinin.The data were analyzed for differential gene expression.According to the expression levels at different times after the application,the key genes involved in shoot tip enlargement were screened out.The screened genes were verified by qRT-PCR.The results are as follows:1)By bioinformatics analysis,a total of 97 cell cycle regulator genes were identified in Zizania japonica,which were divided into Cyclin,CDK,KRP,E2 F and other families according to the functions of different regulatory factors.Among them,9 subfamilies were identified in Cyclin family,including CycA,CycB,CycC,CycD,CycT,CycF,CycL,CycP and SDS subfamily,and the number of each subfamily was 9,8,1,20,4,5,3,7 and 2.Five subfamilies were identified in the CDK family,and the number of each subfamily was 2,4,4,2 and 1,respectively.There are seven KRP genes in the KRP family of Zizania latifolia.There were 8 samples from Zizania latifolia E2 F family,3 samples from DP family,3 samples from DEL family,2 samples from WEE family and 2 samples from Rb family.2)ZIKRP7 and ZICDKB2 can be seen by qRT-PCR results;2,ZlCycD2;2 These three genes are the key genes for the enlargement of Zizania latifolia,among which auxin and cytokinin have negative regulation on the expression of ZIKRP7 gene in shoot tip,and have negative regulation on ZICDKB2;2,ZlCycD2;The expression of 2 has positive regulation effect.3)By in vitro spraying of auxin analogue 2,4-D,it can be seen that auxin can promote the bulge of Zizania latifolia and improve the percentage of pregnant giral,and 100 ppm of2,4-D can significantly increase the percentage of pregnant giral,indicating that auxin can promote the bulge of Zizania latifolia and increase its yield.