A High Temperature-Dependent Mitochondrial Lipase EXTRA GLUME1 Promotes Floral Phenotypic Robustness against Temperature Fluctuation in Rice (Oryza sativa L.)

PLoS Genet. 2016 Jul 1;12(7):e1006152. doi: 10.1371/journal.pgen.1006152. eCollection 2016 Jul.


The sessile plants have evolved diverse intrinsic mechanisms to control their proper development under variable environments. In contrast to plastic vegetative development, reproductive traits like floral identity often show phenotypic robustness against environmental variations. However, it remains obscure about the molecular basis of this phenotypic robustness. In this study, we found that eg1 (extra glume1) mutants of rice (Oryza savita L.) showed floral phenotypic variations in different growth locations resulting in a breakdown of floral identity robustness. Physiological and biochemical analyses showed that EG1 encodes a predominantly mitochondria-localized functional lipase and functions in a high temperature-dependent manner. Furthermore, we found that numerous environmentally responsive genes including many floral identity genes are transcriptionally repressed in eg1 mutants and OsMADS1, OsMADS6 and OsG1 genetically act downstream of EG1 to maintain floral robustness. Collectively, our results demonstrate that EG1 promotes floral robustness against temperature fluctuation by safeguarding the expression of floral identify genes through a high temperature-dependent mitochondrial lipid pathway and uncovers a novel mechanistic insight into floral developmental control.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Environment
  • Flowers / physiology*
  • Gene Expression Regulation, Plant
  • Genotype
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Hot Temperature
  • Humans
  • Lipase / genetics*
  • Lipase / metabolism
  • Lipids / chemistry
  • Mitochondria / enzymology*
  • Mutation
  • Oryza / enzymology
  • Oryza / genetics*
  • Phenotype
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Protein Domains
  • Transcription, Genetic
  • Transcriptome


  • Lipids
  • Plant Proteins
  • Green Fluorescent Proteins
  • Lipase

Grants and funding

This work was supported by grants from Ministry of Science and Technology (2013CBA01402), Strategic Program of Chinese Academy of Sciences (XDA08010205) and National Natural Science Foundation of China (31221063). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.