SEUSS and PIF4 Coordinately Regulate Light and Temperature Signaling Pathways to Control Plant Growth

Junling Huai; Xinyu Zhang; Jialong Li; Tingting Ma; Ping Zha; Yanjun Jing; Rongcheng Lin

doi:10.1016/j.molp.2018.04.005

SEUSS and PIF4 Coordinately Regulate Light and Temperature Signaling Pathways to Control Plant Growth

Mol Plant. 2018 Jul 2;11(7):928-942. doi: 10.1016/j.molp.2018.04.005. Epub 2018 May 2.

Authors

Junling Huai¹, Xinyu Zhang², Jialong Li², Tingting Ma¹, Ping Zha², Yanjun Jing¹, Rongcheng Lin³

Affiliations

¹ Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
² Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China.
³ Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Beijing 100093, China. Electronic address: rclin@ibcas.ac.cn.

PMID: 29729397
DOI: 10.1016/j.molp.2018.04.005

Abstract

Plants continuously monitor environmental conditions (such as light and temperature) and adjust their growth and development accordingly. The transcription factor PHYTOCHROME-INTERACTING FACTOR4 (PIF4) regulates both light and temperature signaling pathways. Here, we identified ENHANCED PHOTOMORPHOGENIC2 (EPP2) as a new repressor of photomorphogenesis in red, far-red, and blue light. Map-based cloning revealed that EPP2 encodes the SEUSS (SEU) transcription regulator. The C terminus of SEU has transcriptional activation activity, and SEU physically interacts with PIF4. Moreover, SEU promotes the expression of many genes, including auxin biosynthetic and responsive genes, and regulates IAA levels in plants. SEU associates with the regulatory regions of INDOLE-3-ACETIC ACID INDUCIBLE6 (IAA6) and IAA19 in a PIF4-independent manner, whereas the binding of PIF4 to these genes requires SEU. Furthermore, mutations in SEU affect H3K4me3 methylation at IAA6 and IAA19, and SEU positively regulates warm temperature-mediated hypocotyl growth together with PIF4. Collectively, our results reveal that SEU acts as a central regulator integrating light and temperature signals to control plant growth by coordinating with PIF4.

Keywords: PIF4; SEU; light; temperature; transcription regulation.

Publication types

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

MeSH terms

Arabidopsis / physiology*
Arabidopsis Proteins / genetics
Arabidopsis Proteins / physiology*
Basic Helix-Loop-Helix Transcription Factors / genetics
Basic Helix-Loop-Helix Transcription Factors / physiology*
Gene Expression Regulation, Plant
Light
Plant Growth Regulators / physiology*
Signal Transduction*
Temperature

Substances

Arabidopsis Proteins
Basic Helix-Loop-Helix Transcription Factors
PIF4 protein, Arabidopsis
Plant Growth Regulators
SEUSS protein, Arabidopsis