Insight into the B3Transcription Factor Superfamily and Expression Profiling of B3 Genes in Axillary Buds after Topping in Tobacco(Nicotiana tabacum L.).

Fei Xia,Mengmeng Cui,Dawei Wang,Tingting Sun,Jiangtao Chao,Junhua Hu,Xiaoxu Li,Shuangjuan Yang,Yuhe Sun,Guanshan Liu,Xiao Wang

doi:10.3390/genes10020164

Abstract

Members of the plant-specific B3 transcription factor superfamily play important roles in various growth and developmental processes in plants. Even though there are many valuable studies on B3 genes in other species, little is known about the B3 superfamily in tobacco. We identified 114 B3 proteins from tobacco using comparative genome analysis. These proteins were classified into four subfamilies based on their phylogenetic relationships, and include the ARF, RAV, LAV, and REM subfamilies. The chromosomal locations, gene structures, conserved protein motifs, and sub-cellular localizations of the tobacco B3 proteins were analyzed. The patterns of exon-intron numbers and arrangement and the protein structures of the tobacco B3 proteins were in general agreement with their phylogenetic relationships. The expression patterns of 114 B3 genes revealed that many B3 genes show tissue-specific expression. The expression levels of B3 genes in axillary buds after topping showed that the REM genes are mainly up-regulated in response to topping, while the ARF genes are down-regulated after topping.

Highlights

Transcription factors (TFs) are an important group of proteins that regulate gene expression at the transcriptional level by binding to specific DNA sequences
The results of sub-cellular localization prediction suggested that 89 B3 proteins are localized to the nuclear, five are localized to the chloroplast, one protein is localized to mitochondrion, and the remaining 21 proteins are localized in the cytoplasm (Table 1, Table S2)
The Arabidopsis ortholog proteins of five tobacco auxin response factor (ARF) localized to the cytoplasmic and chloroplast, ten REMs localized to the cytoplasmic, and two REMs localized to the chloroplast were all localized to the nuclear according to the data of TAIR and NCBI

Summary

Introduction

Transcription factors (TFs) are an important group of proteins that regulate gene expression at the transcriptional level by binding to specific DNA sequences. With the completion of genome sequencing in many plant species, genome-wide identification and analyses of genes encoding plant TFs is straightforward [1]. Genes 2019, 10, 164 and 38 eudicot species with genome sequences, the total number of TF genes identified ranged from to 3714 [2]. Many TF families are present in plants as well as animals, bacteria, and yeast, including the homeodomain, MYB, bHLH, MADS, and bZIP families [1]. Other classes of TFs are considered plant-specific, such as the AP2/EREBP, NAC, WRKY, GRAS, SBP and B3 families [1,3,4,5]

Methods

Results

Conclusion