| Tea is one of the world’s three non-alcoholic beverages,which is not only rich in nutrients,but also has a unique role in health care,deeply loved by the people all over the world.Environment factors strongly affect tea quality during their growth process.During the picking of spring tea,tea gardens frequently suffer from climatic disasters such as low temperatures and frosts,resulting in a decline in tea yield and quality,and serious economic losses.In recent years,the high temperature and drought of tea gardens in summer and autumn have occurred frequently,resulting in a decline in spring tea yield in the coming year,which has also greatly affected the production benefits of tea gardens.Therefore,using molecular biology and other techniques to analyze the molecular mechanism of tea plant’s resistance to temperature stress and excavate the molecular markers related to stress resistance is of great significance for accelerating the selection and breeding of modern tea plant varieties with excellent stress resistance.Our research group found that anthocyanin was involved in the response to temperature stresses and a large number of transcription factors were differentially expressed by comparative transcriptomics and metabolomic analysis.Among them,SQUAMOSA Promoter-binding Protein-like(SBP-box)transcription factor is a kind of plant-specific transcription factor,which is widely involved in plant growth and development,responding to adversity and participating in anthocyanin accumulation.Based on the Camellia sinensis var.sinensis genome data,we made genome-wide analysis of the SBP-box gene family and analyzed the expression pattern after short-term temperature stress.At the same time,we also excavated CsSBP genes which is related to anthocyanin accumulation.The specific results are as follows:1.25 CsSBP genes were identified in Camellia sinensis var.sinensis genome.Phylogenetic tree analysis,this gene family is divided into six groups;13 CsSBP genes in G1,G2 and G5 are the target genes of CsmiR156;promoter analysis shows that CsSBPs gene family responds to various hormones and adversity stresses.2.The expression patterns of SBP-box genes at different time points under short-term low temperature and short-term high temperature stress showed that eight SBP-box genes(CsSBP2,CsSBP3,CsSBP5,CsSBP7,CsSBP8,CsSBP16,CsSBP18,and CsSBP19)were up-regulated expression in both stresses,only CsSBP12 was down-regulated after both low and high temperature stress.3.Under short-term temperature stress,the total anthocyanin content showed a downward trend.The correlation analysis showed that under high temperature and low temperature stress,the genes related to anthocyanin accumulation were different.The correlation between CsSBP8 and anthocyanin was the highest after high temperature stress.CsSBP12 was associated with anthocyanins under both high and low temperature stress.4.Using Gateway reaction,35S:CsSBP8:EGFP and 35S:CsSBP12:EGFP overexpression vectors were constructed.Subcellular localization in epidermal cells of N.benthamiana showed that CsSBP8 is located in the nucleus,while CsSBP12 does not only expression in nucleus,but also has EGFP signal in cell membrane.This study analyzed the bioinformatics characteristics of the SBP-box gene family of Chinese type tea plant and their expression pattern under temperature stress.Two CsSBP genes related to anthocyanin accumulation were excavated,which provided some theoretical basis for the study of the anthocyanin pathway under temperature stress. |
