Functional analysis of the HD-Zip transcription factor genes Oshox12 and Oshox14 in rice

Jingxia Shao; Imran Haider; Lizhong Xiong; Xiaoyi Zhu; Rana Muhammad Fraz Hussain; Elin Övernäs; Annemarie H Meijer; Gaisheng Zhang; Mei Wang; Harro J Bouwmeester; Pieter B F Ouwerkerk

doi:10.1371/journal.pone.0199248

Functional analysis of the HD-Zip transcription factor genes Oshox12 and Oshox14 in rice

PLoS One. 2018 Jul 20;13(7):e0199248. doi: 10.1371/journal.pone.0199248. eCollection 2018.

Authors

Jingxia Shao^{1

2}, Imran Haider^{2

3}, Lizhong Xiong⁴, Xiaoyi Zhu⁵, Rana Muhammad Fraz Hussain², Elin Övernäs⁶, Annemarie H Meijer², Gaisheng Zhang⁷, Mei Wang^{2

8}, Harro J Bouwmeester³, Pieter B F Ouwerkerk²

Affiliations

¹ College of Life Sciences, Northwest A&F University, Shaanxi, People's Republic of China.
² Institute of Biology (IBL), Leiden University, Leiden, The Netherlands.
³ Laboratory of Plant Physiology, Wageningen University and Research Centre, Wageningen, The Netherlands.
⁴ National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan, People's Republic of China.
⁵ Key Laboratory of Biology and Genetic Improvement of Oil Crops of Ministry of Agriculture, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, People's Republic of China.
⁶ Department of Physiological Botany, EBC, Uppsala University, Uppsala, Sweden.
⁷ College of Agronomy, Northwest A&F University, Shaanxi, People's Republic of China.
⁸ Leiden University European Center for Chinese Medicine and Natural Compounds, Leiden, The Netherlands.

Abstract

The homeodomain-leucine zipper (HD-Zip) transcription factor family plays vital roles in plant development and morphogenesis as well as responses to biotic and abiotic stresses. In barley, a recessive mutation in Vrs1 (HvHox1) changes two-rowed barley to six-rowed barley, which improves yield considerably. The Vrs1 gene encodes an HD-Zip subfamily I transcription factor. Phylogenetic analysis has shown that the rice HD-Zip I genes Oshox12 and Oshox14 are the closest homologues of Vrs1. Here, we show that Oshox12 and Oshox14 are ubiquitously expressed with higher levels in developing panicles. Trans-activation assays in yeast and rice protoplasts demonstrated that Oshox12 and Oshox14 can bind to a specific DNA sequence, AH1 (CAAT(A/T)ATTG), and activate reporter gene expression. Overexpression of Oshox12 and Oshox14 in rice resulted in reduced panicle length and a dwarf phenotype. In addition, Oshox14 overexpression lines showed a deficiency in panicle exsertion. Our findings suggest that Oshox12 and Oshox14 may be involved in the regulation of panicle development. This study provides a significant advancement in understanding the functions of HD-Zip transcription factors in rice.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

DNA, Plant / genetics*
DNA, Plant / metabolism
Gene Expression Regulation, Developmental
Gene Expression Regulation, Plant*
Hordeum / classification
Hordeum / genetics*
Hordeum / growth & development
Hordeum / metabolism
Inflorescence / genetics
Inflorescence / growth & development
Inflorescence / metabolism
Leucine Zippers
Oryza / classification
Oryza / genetics*
Oryza / growth & development
Oryza / metabolism
Phylogeny
Plant Development / genetics
Plant Proteins / genetics*
Plant Proteins / metabolism
Protein Binding
Protoplasts / metabolism
Transcription Factors / genetics*
Transcription Factors / metabolism

Substances

DNA, Plant
Plant Proteins
Transcription Factors

Grants and funding

This work was supported by funding to JS from China Scholarship Council (CSC, 2007U27088, http://www.csc.edu.cn/) and National Natural Science Foundation of China (31770345, http://www.nsfc.gov.cn/). This work was supported by the Higher Education Commission (HEC) of Pakistan and the King Abdullah University of Science and Technology (KAUST) to IH. MW and PBFO were supported by the KNAW Program Scientific Alliance (04-PSA-BD-04, www.knaw.nl). AHM was supported by TF-STRESS (QLK3-CT-2000-00328). PBFO was also supported by CEDROME (INCO-CT-2005-015468). TNO, the Netherlands (https://www.tno.nl/en/) provided funding in the form of salary for MW; MW was also supported by the KNAW projects via a subsidy allowing travel and purchasing consumables for the PhD students working on this project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.