Arabidopsis MHP1, a homologue of yeast Mpo1, is involved in ABA signaling

Min Zheng; Tao Peng; Tingting Yang; Jiawen Yan; Kezhen Yang; Dong Meng; Yi-Feng Hsu

doi:10.1016/j.plantsci.2020.110732

Arabidopsis MHP1, a homologue of yeast Mpo1, is involved in ABA signaling

Plant Sci. 2021 Mar:304:110732. doi: 10.1016/j.plantsci.2020.110732. Epub 2020 Oct 25.

Authors

Min Zheng¹, Tao Peng², Tingting Yang², Jiawen Yan², Kezhen Yang³, Dong Meng⁴, Yi-Feng Hsu⁵

Affiliations

¹ Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Southwest University, Chongqing 400715, China. Electronic address: min007@swu.edu.cn.
² Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Southwest University, Chongqing 400715, China.
³ Key Laboratory of Plant Molecular Physiology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
⁴ Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China.
⁵ Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Southwest University, Chongqing 400715, China. Electronic address: yifenghsu06@swu.edu.cn.

PMID: 33568285
DOI: 10.1016/j.plantsci.2020.110732

Abstract

Sphingolipids and their intermediates play multiple roles in biological processes. The sphingoid long-chain base component of sphingolipids has emerged as a participant in the regulation of plant biotic and abiotic stress responses. The phytohormone abscisic acid (ABA) regulates many stress responses in plants for environmental adaptation. However, the relationship between the sphingoid bases and ABA is undetermined. In this study, mhp1-1 (the yeast Mpo1 homolog in plants) was isolated through a sodium chloride (NaCl)-sensitivity screen of Arabidopsis transfer DNA (T-DNA) insertion mutants. mhp1-1 was hypersensitivity to salt/osmotic stress and ABA. MHP1 encodes a protein with a domain of unknown function 962 (DUF962). Endoplasmic reticulum-localized MHP1 was found to interact with ABI1. MHP1, a homolog of yeast dioxygenase Mpo1, rescued the growth arrest of mpo1Δ cells caused by ER stress, suggesting functional homology of MHP1 to Mpo1. Overall, MHP1 plays important roles in response to ABA.

Keywords: ABA signaling; ABI1; ER stress; MHP1; Mpo1; Phytosphingosine.

MeSH terms

Abscisic Acid / metabolism*
Arabidopsis / genetics*
Arabidopsis / metabolism
Arabidopsis / physiology
Arabidopsis Proteins / metabolism
Arabidopsis Proteins / physiology*
Endoplasmic Reticulum / metabolism
Microscopy, Confocal
Nuclear Proteins / metabolism
Nuclear Proteins / physiology*
Osmotic Pressure
Plant Growth Regulators / metabolism*
Reverse Transcriptase Polymerase Chain Reaction
Salt Stress

Substances

AT1G18720 protein, Arabidopsis
Arabidopsis Proteins
Nuclear Proteins
Plant Growth Regulators
Abscisic Acid