Genome-wide Analysis Of The WD40 Protein Family In Medicago Truncatula And Verification Of RACK1 Biological Function

WD40 proteins are a very diverse regulatory protein family,and it is widely involved in many cell processes.It has been reported in many plants,but there is no related report in Medicago truncatula.This study was to identify and predict the function of WD40 gene family in Medicago sativa.The results were as follows:1.202 MtWD40 genes of Medicago truncatula were identified in the latest genome of Medicago truncatula genome.The phylogenetic tree analysis was carried out with 232 AtWD40genes in Arabidopsis.There were strong gene conservation and specific functional gene expansion in the evolution process of the two plants.The WD40s protein were divided into 14 subgroups by the domain prediction.The phylogeny,chromosome location and repeat events of the gene family in Medicago truncatula.were reviewed.The gene function of MtWD40 was annotated by the enrichment analysis of go and KEGG classification.The data of 182 genes expressed in different tissues were downloaded from the chip website of Medicago truncatula..The expression map of MtWD40 genes were analyzed under biological stress and abiotic stress.The expression of MtWD40 genes were different in different tissues,and the response to biological and abiotic stress was also analyzed.2.The prediction of RACK1 subcellular localization and tobacco subcellular localization in WD40 family showed that the gene expression site was located in cytoplasm.The phylogenetic tree analysis showed that the relationship between RACK1 and Nicotianatabacum and Medicago sativa was close,and the homology was 99%.The promoter sequence analysis showed that the promoter of RACK1 gene contains MeJA and photoresponse elements,which may be involved in MeJA and abiotic stress pathway.The complementary function test of yeast mutant proved that RACK1 can improve the reproduction speed of yeast.3.The expression of RACK1 was the highest in leaves and the lowest in roots.RACK1 is a response factor of NaCl and MeJA,and it is not sensitive to ABA response.4.Compared with wild type,the height of transgenic plants was significantly increased,the length and quantity of lateral branches were significantly increased,and the leaf phenotype difference was obvious.It was suggested that RACK1 gene might be involved in the growth and development regulation of Medicago sativa.