Characterization of the bZIP Transcription Factor Family in Pepper ( Capsicum annuum L.): CabZIP25 Positively Modulates the Salt Tolerance

• Published in: Frontiers in plant science Vol. 11; p. 139
• Main Authors: Gai, Wen-Xian, Ma, Xiao, Qiao, Yi-Ming, Shi, Bu-Hang, Ul Haq, Saeed, Li, Quan-Hui, Wei, Ai-Min, Liu, Ke-Ke, Gong, Zhen-Hui
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 26-02-2020
• Subjects: abiotic stress; CabZIP family; CabZIP25; pepper (Capsicum annuum L.); Pepper Genome Databases; Plant Science; salt tolerance; pepper (Capsicum annuum L.); salt tolerance; Pepper Genome Databases; CabZIP25; CabZIP family; abiotic stress
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2020.00139

The basic leucine zipper (bZIP) proteins compose a family of transcription factors (TFs), which play a crucial role in plant growth, development, and abiotic and biotic stress responses. However, no comprehensive analysis of bZIP family has been reported in pepper (
L.). In this study, we identified and characterized 60 bZIP TF-encoding genes from two pepper genomes. These genes were divided into 10 groups based on their phylogenetic relationships with
genes from
. Six introns/exons structural patterns within the basic and hinge regions and the conserved motifs were identified among all the pepper bZIP proteins, on the basis of which, we classify them into different subfamilies. Based on the transcriptomic data of Zunla-1 genome, expression analyses of 59 pepper
genes (not including
of CM334 genome), indicated that the pepper
genes were differentially expressed in the pepper tissues and developmental stages, and many of the pepper
genes might be involved in responses to various abiotic stresses and phytohormones. Further, gene expression analysis, using quantitative real-time PCR (qRT-PCR), showed that the
gene was expressed at relatively higher levels in vegetative tissues, and was strongly induced by abiotic stresses and phytohormones. In comparing with wild type
, germination rate, fresh weight, chlorophyll content, and root lengths increased in the
overexpressing
under salt stress. Additionally,
silenced pepper showed lower chlorophyll content than the control plants under salt stress. These results suggested that
improved salt tolerance in plants. Taken together, our results provide new opportunities for the functional characterization of bZIP TFs in pepper.