Identification Of Sugar Beet MAPK Family Genes And Expression Studies Under Stress

Mitogen activated protein kinase(MAPK)is a ubiquitous signal transduction module factor in eukaryotic cells.It plays an important role in plant immune response,development and differentiation.Therefore,this study screened and identified the members of sugar beet MAPK gene family,provided a reference for using the function of sugar beet MAPK gene family,and provided a theoretical basis for genetic improvement in sugar beet breeding.Seven members of sugar beet MAPK family were screened and identified for bioinformatics analysis,including protein conserved domain,gene structure,evolutionary relationship,chromosome localization,protein interaction and 3D structure.In order to explore the expression pattern of Bv MAPKs in stress,two sugar beet MAPK genes related to salicylic acid(SA)and methyl jasmonate(Me JA)stress,Bv MAPK4 and Bv MAPK7,were obtained from sugar beet susceptible variety KWS9147.Sugar beet Seedlings were induced by biological stress and hormone signal,and analyzed by q RT-PCR.The results are as follows:(1)Seven sugar beet MAPK family members were screened by bioinformatics.Their Gene IDS were LOC104887071,LOC104893685,LOC104892250,LOC104889027,LOC104903118,LOC104907978 and LOC104889438 respectively.In addition,MAPK family genes are unevenly distributed on four chromosomes.The protein encoded by the gene contains 366 ? 604 amino acids,with a molecular weight of 42144.29 ? 68 964.33 D and an isoelectric point of 5.40 ? 8.85.It belongs to weakly acidic and weakly basic proteins,with 4 ? 11 exons.The T-loop loop of Bv MAPK2 and Bv MAPK6 is TDY,Subcellular localization was mostly located in the cytoplasm.Eleven protein motifs were analyzed,of which motif 6 was T-LOOP.The cis elements predicted in the putative promoter region showed that sugar beet MAPK family was affected by biological and abiotic stresses and hormones.(2)The expression of Bv MAPK4 and Bv MAPK7 genes in the leaves of sugar beet susceptible variety KWS9147 seedlings under stress was studied by q RT-PCR.The results showed that: After Salicylic acid(SA)induction,the expression of Bv MAPK4 gene reached the peak at 4h,and the overall trend was up-regulation.The expression of Bv MAPK7 gene was strongly induced at 24 hours and was generally down regulated;After Methyl Jasmonate(Me JA)induction in Sugar beet seedling leaves,the overall expression trend of Bv MAPK4 gene was down-regulated,and Bv MAPK7 the overall expression trend of genes was up-regulated;After inoculating the leaves of sugar beet seedlings with Cercospora for biological stress,it was found that the expression trend of Bv MAPK4 and Bv MAPK7 genes were up-regulated,which played an important role in the regulation of biological stress of sugar beet corresponding to Cercospora.