Identification and Analysis of MYB Transcription Factors Related to Salt Stress in Pyrus betulaefolia based on Transcriptome Information
Myeloblastosis(MYB)is one of the most common transcription factor families in plants,which widely takes part in various adversities responses including salt stress.So far,there is still no systematic comparative analysis on the expression pattern of MYB family among various ecotypes with different salt tolerance abilities from the same species.Based on the transcriptome sequencing(RNA-Seq)data from the salt-tolerant ecotype and common ecotype of Pyrus betulaefolia,the differentially expressed PbMYBs genes before and after salt stress were screened and annotated in this study.Then,their conserved domains were classified,subcellular localizations were predicted and the phylogenetic tree was constructed.TBtools was used to draw the heatmaps to analyze the differential expression pattern of PbMYBs genes in roots,stems and leaves from the salt-tolerant ecotype and common ecotype of P.betulaefolia.By using transcriptome analysis tools,129 PbMYBs transcription factors were annotated and selected from the RNA-Seq data,which differentially expressed in 2 ecotypes of P.betulaefolia after salt stress.These genes can be divided into 3 categories(1R-MYB,R2R3-MYB and 3R-MYB)according to their structural characteristics.The number of PbMYBs genes distributed on chromosome 15 of P.betulaefolia was the largest.The phylogenetic trees of MYB families were constructed,which showed that the PbMYBs family of P.betulaefolia contained 3 major branches,and 23 evolutionary branches.The results of the subcellular localization demonstrated that 42 PbMYBs were located in the extracellular,and 87 PbMYBs were located in the nucleus.Analysis of the differential expression pattern of PbMYBs based on transcriptome data showed that PbMYBs genes in P.betulaefolia may be involved in the transcriptional regulation of different organs in response to salt stress.Additionally,the results of real-time quantitative PCR further verified that some PbMYBs transcription factors may play a role in stress regulation in the roots,stems or leaves of P.betulaefolia,respectively.During the process of salt stress,the transcriptional regulation of 129 PbMYBs members in response to stress were diversity in various organs.The results of real-time quantitative PCR further verified that different PbMYBs transcription factors were up-regulated or down-regulated to response to salt stress signals in the roots,stems or leaves of P.betulaefolia,respectively.The results provide the relative information for further research on gene structure and biological function of the MYB family in P.betulaefolia.