Identification and Expression Analysis of the SBP-box Gene Family Related to Abiotic Stress in Tea Plant (Camellia sinensis (L.) O. Kuntze)

Abstract

SQUAMOSA promoter binding protein (SBP)-box proteins are plant-specific transcription factors (TFs) and play crucial roles in a variety of physiological processes, including plant growth and development, signal transduction, and stress response. However, SBP-box family genes have not been well characterized in tea plant. In the present study, we identified 16 CsSBP genes in tea plant based on the tea plant genomic data. Phylogenetic analysis of SBP-box proteins from tea plant, Arabidopsis, and rice divided these proteins into nine groups (A–I). The number of exon–intron varied among the groups. The SBP-box genes in a same group shared similar exon–intron structures and motif locations. Prediction of miRNA target sites revealed that six CsSBPs genes contained a miR156 target site, while seven were targeted by miR157. RT-qPCR analysis revealed tissue/organ-specific expression patterns of CsSBP genes. In addition, their expression patterns in response to different phytohormone treatments and abiotic stresses were also investigated. This work provides base foundation for understanding the crucial roles of CsSBP genes in plant development and other biological processes.