Isolation Of Possible Candidate Genes HvMYC1 And HvMYB1 Controlling Blue Grain Traits In Barley By BSA·QTL-seq

Barley,also known as barley,belongs to the genus Barley of Gramineae.Colored highland barley contains high levels of nutrients,such as anthocyanins,phenolic compounds,proteins and trace elements.Blue-grained highland barley is a kind of colored highland barley,which is formed by the deposition of anthocyanins in the paste layer of highland barley.The main experimental results of this study are as follows:1.High-throughput sequencing of the blue-grain genome of highland barley was carried out by BSA.QTL-seq method.The distribution of 7,452,819 SNPs and 7chromosomes was determined.An obvious QTL region was obtained and 853 genes were predicted in the region,including 5 MYB and 5 bHLH related genes.A phylogenetic tree was constructed with four MYB genes in the QTL region and MYB genes in Arabidopsis thaliana.It was found that only one candidate gene HvMYB1 and MYB genes regulating anthocyanin synthesis were clustered into one group.It was also found that there was only one MYC candidate gene HvMYC1 and MYC genes clustered together in the candidate gene segment.This implies that they may be candidate genes for controlling Blue-grained traits,and the comparison is consistent with previous transcriptome sequencing results.Moreover,the QTL analysis results of candidate genes HvMYC1 and HvMYB1 were within 525.9-541.7Mb in the peak QTL region related to the traits of blue-grain wheat,which further indicated that these two genes were most likely to be the main genes controlling the blue-grain traits.2.The sequence structure analysis of candidate genes HvMYC1 and HvMYB1 showed that the HvMYC1 gene,with a full length of 1668 bp,encoded 555 amino acids and had a typical structural domain of bHLH protein related to the regulation of anthocyanin synthesis.The HvMYB1 gene,with a total length of 732 bp and 265 amino acids encoded,is a typical R2R3 myb-like transcription factor with a domain in R3 that interacts with the bHLH protein.3.Bioinformatics analysis of candidate genes HvMYC1,its initiation codon ATG,termination codon is the TAG,the molecular weight of 61333.71,isoelectric point is8.47,there are two belong to the bHLH super family conservative district,predict its protein has certain hydrophilicity,irregular secondary structure with alpha helix andcoiled as the main part,HvMYC1 proteins across the membrane area and not used for film outside.4.The HvMYC1 gene sequence was compared in the barley genome database,and it was found to be located in the range of 534044159 to 534066299 of barley 4H chromosome,spanning 19569 bases and containing 7 sections.Among them,the insertion of a large fragment sequence in the middle of the coding region sequence of HvMYC1 gene may affect the transcription function of the coding region,thus affecting the expression of this gene and thereby affecting the synthesis of anthocyanin.5.The sequence of HvMYB1 gene is consistent in the transcriptome of blue-white highland barley,and the genomic DNA sequence of its coding region is completely consistent,so the promoter of HvMYB1 gene of blue-white highland barley is separated.After sequencing,it was found that there were differences between the promoter sequences of blue-white highland barley.Previous transcriptome analysis has proved that there were differences in the expression level of HvMYB1 in blue-white highland barley,so the differences in promoter sequences may lead to the differences in the traits of blue-white highland barley.