Please wait a minute...
J Integr Plant Biol
Betula platyphylla BpHOX2 transcription factor binds to different cis-acting elements and confers osmotic tolerance
Zilong Tan1, 2, 3 , Xuejing Wen1, 2 and Yucheng Wang1*
1CAS Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
2State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
3Graduate School, University of Chinese Academy of Sciences, Beijing 100049, China

*Correspondence: : Yucheng Wang (wangyucheng@ms.xjb.ac.cn)
doi: 10.1111/jipb.12994
Abstract

The homeodomain‐leucine zipper (HD‐Zip) proteins play crucial roles in plant developmental and environmental responses. However, how they mediate gene expression to facilitate abiotic stress tolerance remains unknown. In the present study, we characterized BpHOX2 (encoding a HD‐Zip I family protein) from birch (Betula platyphylla). BpHOX2 is predominately expressed in mature stems and leaves, but expressed at a low level in apical buds and roots, suggesting that it has tissue‐specific characteristics. BpHOX2 expression was highly induced by osmotic and salt, but only slightly induced by abscisic acid. Overexpression of BpHOX2 markedly improved osmotic tolerance, while knockdown of BpHOX2 increased sensitivity to osmotic stress. BpHOX2 could induce the expression of pyrroline‐5‐carboxylate synthase, peroxidase, and superoxide dismutase genes to improve proline levels and the reactive oxygen species scavenging capability. Chromatin immunoprecipitation sequencing combined with RNA sequencing showed that BpHOX2 could bind to at least four cis‐acting elements, including dehydration‐responsive element “RCCGAC”, Myb‐p binding box “CCWACC,” and two novel cis‐acting elements with the sequences of “AAGAAG” and “TACGTG” (termed HBS1 and HBS2, respectively) to regulate gene expression. Our results suggested that BpHOX2 is a transcription factor that binds to different cis‐acting elements to regulate gene expression, ultimately improving osmotic tolerance in birch.

--------------------------------------------------------------------------------------------------------------------
Received: 05 May 2020      Accepted:    Online on:18 July 2020
This Article
   Full Text  
   Full Text (PDF) 
   Supporting information
Services
   E-mail Link to this Article
   Export Citation for this Article
Citing Articles
   Cited By
Google Scholar
PubMed
Editorial Office, Journal of Integrative Plant Biology, Institute of Botany, CAS
No. 20 Nanxincun, Xiangshan, Beijing 100093, China
Tel: +86 10 6283 6133 Fax: +86 10 8259 2636 E-mail: jipb@ibcas.ac.cn
Copyright © 2020 by the Institute of Botany, the Chinese Academy of Sciences
Online ISSN: 1744-7909 Print ISSN: 1672-9072 CN: 11-5067/Q
网站备案号:京ICP备16067583号-22