Abstract
APETALA2/ethylene-responsive factor (AP2/ERF) is one of the largest transcription factor (TF) families in plants, which play important roles in regulating plant growth, development, and response to environmental stresses. Ammopiptanthus nanus, an unusual evergreen broad-leaved shrub in the arid region in the northern temperate zone, demonstrates a strong tolerance to low temperature and drought stresses, and AP2/ERF transcription factors may contribute to the stress tolerance of A. nanus. In the current study, 174 AP2/ERF family members were identified from the A. nanus genome, and they were divided into five subfamilies, including 92 ERF members, 55 dehydration-responsive element binding (DREB) members, 24 AP2 members, 2 RAV members, and 1 Soloist member. Compared with the other leguminous plants, A. nanus has more members of the DREB subfamily and the B1 group of the ERF subfamily, and gene expansion in the AP2/ERF family is primarily driven by tandem and segmental duplications. Promoter analysis showed that many stress-related cis-acting elements existed in promoter regions of the DREB genes, implying that MYB, ICE1, and WRKY transcription factors regulate the expression of DREB genes in A. nanus. Expression profiling revealed that the majority of DREB members were responsive to osmotic and cold stresses, and several DREB genes such as EVM0023336.1 and EVM0013392.1 were highly induced by cold stress, which may play important roles in cold response in A. nanus. This study provided important data for understanding the evolution and functions of AP2/ERF and DREB transcription factors in A. nanus.
Highlights
We investigated the segmental duplication of the APETALA2/ethylene-responsive factor (AP2/ERF) gene family in the A. nanus genome using synteny analysis (Figure 7)
Our results showed that promoter regions of AnAP2/ERF genes contained a certain number of MYB, MYC, and WRKY binding elements, suggesting that certain MYB, MYC, and WRKY transcription factors can regulate the expression of the Apetala 2 (AP2)/ERF family genes in A. nanus
A. nanus, and these genes were further divided into five subfamilies, including ERF, dehydration-responsive element binding (DREB), AP2, related to ABI3/VP1 (RAV), and Soloist
Summary
Plants are inevitably subjected to various adverse conditions in their life cycle, such as cold stress, drought stress, and salt stress, which negatively affect their growth, development, and yield [1].Plants respond to environmental stresses at both cellular and molecular levels by regulating the expression of many genes via a variety of signal transduction pathways, and several transcription factor (TF) families, including APETALA2/ethylene-responsive factor (AP2/ERF), WRKY, NAC (NAM, ATAF1, 2, and CUC2), and MYB (myeloblastosis oncogene), play crucial roles in stress signal transduction [2].AP2/ERF family is one of the largest families in the plant kingdom, and proteins in this family contain at least one AP2/ERF DNA-binding domain that consists of 60~70 conserved amino acids [3].The AP2 domain is important for the binding activity to the cis-acting elements including the Plants 2020, 9, 455; doi:10.3390/plants9040455 www.mdpi.com/journal/plantsPlants 2020, 9, 455 dehydration-responsive element/C-repeat (DRE/CRT) and the GCC box in the promoter regions of target genes of AP2/ERF TFs [4,5]. AP2/ERF family is one of the largest families in the plant kingdom, and proteins in this family contain at least one AP2/ERF DNA-binding domain that consists of 60~70 conserved amino acids [3]. The AP2/ERF family is divided into five subfamilies, i.e., ethylene-responsive element binding factors (ERFs), dehydration-responsive element binding (DREB), AP2, related to ABI3/VP1 (RAV), and Soloist, based on the characteristics of their conserved domains. Both the ERF and DREB subfamily members contain a single AP2 domain, but important differences exist in some specific amino acid sites of their AP2 domains [6]. The AP2 subfamily members contain two adjacent AP2 domains, and the RAV subfamily members possess both an AP2 domain and a B3 domain
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
