The Resistant Candidate Genes (SCMV2) Mining、Cloning And Analysis Of Variation Locus To Sugar Cane Mosaic Virus In Maize

Corn sugar cane mosaic virus （SCMV） caused maize dwarf mosaic virus disease is one of the major diseases of maize producing areas in China and Europe, cultivate resistance disease new varieties is the most effective way to overcome this disease. Disease related genetic, gene mapping and gene cloning aspect of the research work more, but less on chromosome 3 resistance disease gene cloning. In this article, element analysis integrate corn sugar cane mosaic virus resistance gene QTL information, identify candidate genes associated with the disease in the "consistency QTL" section and cloned by bioinformatics candidate genes were functionally SNP analysis and identification. The main research is as follows:（1）Collected on maize chromosome 3 Resistance to Sugarcane Mosaic virus gene QTL mapping information, by means maize genetic map IBM2 2008 Neighbors were integrated. Using element analysis, we identified a "consistency" antiviral QTL, genetic map IBM22008 Neighbors coverage for 2.97 cM, located at 305.51 cM map. By "consistency" resistance QTL interval gene sequence was bioinformatics analyzed,we found that in the "consistency" QTL segment gene sequences GRMZM2G436226_T01 have resistance function domain, identified as the Resistance to Sugarcane Mosaic Virus candidate genes.（2）In the region that determined candidate genes, we performed gene-cloning work. Cloning coding region of the gene, in the candidate gene interval. Have been obtained genomic sequence of high resistance materials 2988 bp and high sense materials 2990 bp, we use DNAMAN for bioinformatics analysis, the cloned sequence varying degrees of anti-sense material contrast, Mutation loci obtained 147, four of which distinct mutations.（3）Protein structure analyze gene sequences of highly resistant material and highly infection showed:The protein of Qi319 contains 945 amino acids and the protein of Ji63 contains 919 amino acids. The hydrophilic amino acids of resistant material was obviously higher than that of highly infection materials 。 Analysis of protein nature do not exist the transmembrane structure, may be proteins that localized in the cytoplasm matrix or cytoplasmic matrix.（4）Analyzed the function of proteins conserved domains found that high resistance materials all contain RX-CC_like, AAA₂2, NB-ARC. However, in the analytical results of high sensitive material, there is no presence of three structures at the same time. T nucleotide deletions in 211st place of the gene sequences, resulting in sequence of an amino acid from the original arginine into a glycine, eventually leading to material of a high sense does not contain RX-CC_like homology domain. Sequence analysis from material of different high sense, we found that only materials （Zheng 58） contain conserved domains of NB-ARC, because its nucleotide sequence is inserted a base C at 998th, resulting in an amino acid sequence mutation, from the original glutamine into serine.（5）According to the high resistance material and high infection material sequence contrast from 2648 to 2656 insert nine bases,develop new Indel marker, use the maker detection marker genotype of 100 inbred line, combined with resistance performance results, the effectiveness of the analysis two marker auxiliary choose. Indel1186-9 marker probability of choice more than 80%, disease resistance choose the probability reach 92.86%. Indel1186-9 marker make disease resistance level from an average of 7.26 up to an average of 2.4.