WUSCHEL-related homeobox gene PagWOX11/12a responds to drought stress by enhancing root elongation and biomass growth in poplar

Abstract

In plants, a large root system improves the uptake of water and nutrients and is important for responding to drought stress. The poplar WUSCHEL-related homeobox (WOX) transcription factor promotes adventitious rooting, but its regulation of root growth in response to drought stress remains elusive. In this study, we found that PagWOX11/12a from hybrid poplar 84K (Populus alba×Populus glandulosa) is expressed predominantly in the roots and is strongly induced by drought stress. Compared with nontransgenic 84K plants, transgenic poplar plants overexpressing PagWOX11/12a displayed increased root biomass and enhanced drought tolerance, while opposite phenotypes were observed for PagWOX11/12a dominant repression (DR) plants. PagWOX11/12a functions as a nuclear transcriptional activator with a transactivation domain at the C-terminus. In addition, PagERF35 was found to specifically bind to a dehydration-responsive element (DRE) within the PagWOX11/12a promoter and activate PagWOX11/12a gene expression. These results indicate that PagERF35 may activate PagWOX11/12a expression in response to drought stress by promoting root elongation and biomass, thereby increasing drought tolerance of poplar.

Genome-Wide Identification and Expression Profiling of the WOX Gene Family in Citrus sinensis and Functional Analysis of a CsWUS Member

“…The bait clone with the empty prey pGADT7 and co-transformed cells on SD/-Ade/-His/-Leu/-Trp medium was transformed into yeast AH109 strain. Transactivation activity was determined by a previously reported method [ 19 ]. Cs WUS DNA binding activity was investigated by the Matchmaker TM Gold Yeast-one Hybrid Library screening system according to the user manual (Clontech, Mountain View, CA, USA).…”

“…Arabidopsis WOX members have been extensively studied, and their orthologs have exhibited diverse functions in numerous development processes [ 10 , 11 , 12 , 13 ], along with rice and maize [ 8 , 12 ]. Besides Arabidopsis , genome-wide studies have also been conducted on the W OX gene families of woody plants such as walnut [ 10 ], physic nut [ 14 ], grapes [ 15 , 16 ], peach, pear, apricot [ 17 ], coffee [ 18 ], and poplar [ 19 ]. In these plants, WOX genes are involved in vital regulatory networks that link the developmental mechanisms in plants, including shoot apical meristem, lateral organ development, plant stem cell maintenance, and floral determinacy [ 5 , 20 , 21 , 22 ].…”

“…Some WOX genes in Arabidopsis are involved in hormone signaling transduction pathways. For example, AtWOX4 , AtWOX5 , and AtWOX11 regulate auxin signaling that determines lateral organ and apical root growth [ 19 , 20 , 30 ]. WOX1 homologs have been demonstrated to control leaf blade outgrowth in Zea mays , Petunia hybrida , Medicago truncatula , and Nicotiana tabacum [ 5 , 31 , 32 ].…”

Transcriptional Regulation of Drought Response in Arabidopsis and Woody Plants

“…PagWOX11/12a, belonging to the WUSCHELrelated homebox (WOX) TF familiy, positively regulates drought tolerance by increasing root growth. In addition, co-expression analysis and transcriptional activation assay suggest that ERF and WOX may form a regulatory module responding to drought stress (Wang et al, 2019). MdERF38 was shown to interact with MdMYB1 to promote anthocyanin biosynthesis in response to drought stress in apple .…”

ThHSFA1 Confers Salt Stress Tolerance through Modulation of Reactive Oxygen Species Scavenging by Directly Regulating ThWRKY4

“…Then, the seedlings were transferred to 1/2 MS solid medium and grown for 48 h. Transgenic T . hispida was used for ChIP, and ChIP was conducted as described previously [ 50 , 51 ]. The sonicated chromatin was immunoprecipitated with an anti-GFP antibody (ChIP) or immunoprecipitated without an anti-GFP antibody (Mock).…”