Trihelix family transcription factors in tea plant (Camellia sinensis): identification, classification, and expression profiles response to abiotic stress.

Tea plant is an economic crop in China. Trihelix family transcription factor, also known as GT factor, is one of plant-specific TF families in plant. Its functions have been recognized in the development and stress tolerance in various plants. However, the trihelix TFs and its roles in abiotic stress tolerance in tea plant remains unclear. In this study, ten putative trihelix family TFs were identified from the transcriptome of tea plant, and divided into five clades. The leaves of two tea plant cultivars (‘Yingshuang’ and ‘Huangjinya’) under four abiotic stress treatments (38, 4 °C, salt and drought) were collected. Then, the expression profiles of two genes under abiotic stress treatments were detected and analyzed by qRT-PCR. The protein–protein interactions of trihelix family between C. sinensis and Arabidopsis were also performed. The expression levels of CsGT1-3 and CsGT2-1 were varied in the two tea plant cultivars. Meanwhile, CsGT1-3 and CsGT2-1 were differentially induced by the abiotic stresses. Up-regulation of CsGT1-3 and CsGT2-1 expressions by the induction of salt stress was observed. Our results might suggest that the transcriptome-based analysis was considered to be an available method to identify the identification and characterization of trihelix family TFs in C. sinensis.