Abstract:

In order to systematically analyze the sequence characteristics and expression pattern of BolMYC2 in broccoli,and to explore the role of BolMYC2 in response to the infection of soft rot pathogens in broccoli,the coding sequence of BolMYC2 gene was cloned by PCR amplification using broccoli cDNA as a template.The basic properties of BolMYC2 protein were analyzed by bioinformatics software.BolMYC2-EGFP fusion expression vector was constructed and transiently transformed into Nicotiana benthamiana to analyze the subcellular localization of BolMYC2 protein.The transcriptional expression characteristics of BolMYC2 in different tissues of broccoli and the transcriptional expression characteristics of BolMYC2 under the stress of soft rot pathogens were analyzed by qRT-PCR.The results showed that the coding sequence of BolMYC2 was 1 833 bp,encoding 610 amino acids.The theoretical molecular weight was 66.297 ku and the theoretical isoelectric point was 5.21.BolMYC2 was an unstable hydrophilic protein without transmembrane structure and signal peptide.Conserved domain analysis showed that BolMYC2 protein contained the conserved domains bHLH-MYC_N and bHLH_SF of MYC transcription factor family.Phylogenetic tree analysis showed that BolMYC2 protein was closely related to brussels sprouts.Analysis of the cis-acting elements of the BolMYC2 promoter showed that it contained cis-acting elements involved in light response,hormone response,stress response,and multiple MYB,MYC,and WRKY transcription factor recognition elements.Subcellular localization results showed that BolMYC2 was localized in the nucleus.BolMYC2 was highly expressed in leaves and seeds.In addition,the expression level of BolMYC2 decreased first and then increased after broccoli was infected by soft rot pathogens,suggesting that BolMYC2 plays an important role in broccoli response to biotic stress.

Key words: Broccoli, Soft rot disease, BolMYC2 gene, Expression analysis, Subcellular localization

CLC Number: 

• S635.3