Identification, bioinformatics analysis, and expression profiling of the bHLH supergene family members in Beta vulgaris

Abstract

Abstract Background Basic helix-loop-helix (bHLH) is one of the largest families of transcription factors in plants, animals, and microorganisms and plays an important complex physiological role in plant growth and development, metabolic regulation, and adversity stress. With the development of bioinformatics, bHLH transcription factor families have been continuously identified and analyzed, but the bHLH family of Beta vulgaris has not yet been analyzed and reported. Results Using whole-genome sequencing data from B. vulgaris, we identified 96 BvbHLHs genes with relatively large differences in physicochemical properties that were unevenly distributed across nine chromosomes. A phylogenetic developmental tree was constructed using the BvbHLH and AtbHLH proteins, which were ultimately categorized into 21 subgroups and one unclassified group. The gene structure, conserved motifs, gene duplication events, and evolutionary relationships of the 96 BvbHLH genes were analyzed using various bioinformatics approaches. The results showed that motifs 1 and 2 were widely distributed in BvbHLHs, had highly conserved gene structures within the same subfamily, presence of four tandem duplication events, and six pairs of segmental duplication events, and were more closely homologous to dicotyledonous plants. We also analyzed the tissue-specific expression of 12 BvbHLH genes during B. vulgaris maturity and their responses to eight abiotic stresses using quantitative real-time polymerase chain reaction. Conclusions A total of 96 BvbHLH genes were identified. Bioinformatics analysis of the gene structure, evolutionary relationship, and expression pattern of the B. vulgaris bHLH gene family lays a foundation for the evolution of the bHLH gene family and the screening of candidate genes in B. vulgaris.