Identification and Characterization of the Basic Helix-Loop-Helix Transcription Factor Family in Pinus massoniana

Abstract

The basic helix-loop-helix (bHLH) protein transcription factor family is the most widely distributed transcription factor family in eukaryotes. Members of this family play important roles in secondary metabolic biosynthesis, signal transduction, and plant resistance. Research on the bHLH family in animals is more extensive than that in plants, and members of the family in plants are classified according to the classification criteria for those in animals. To date, no research on the bHLH gene family in Pinus massoniana (Masson pine) has been reported. In this study, we identified 88 bHLH genes from four transcriptomes of Masson pine and performed bioinformatics analysis. These genes were divided into 10 groups in total. RT-PCR analysis revealed that the expression levels of the six genes increased under abiotic stress and hormone treatments. These findings will facilitate further studies on the functions of bHLH transcription factors.