A β‐ketoacyl carrier protein reductase confers heat tolerance via the regulation of fatty acid biosynthesis and stress signaling in rice

Thermotolerance 2. Zero hunger 0303 health sciences Research Fatty Acids Oryza 15. Life on land Plants, Genetically Modified Droughts 03 medical and health sciences Gene Expression Regulation, Plant Stress, Physiological XXXXXX - Unknown Carrier Proteins Oxidoreductases Phylogeny Plant Proteins
DOI: 10.1111/nph.17619 Publication Date: 2021-07-14T14:21:25Z
ABSTRACT
Summary Heat stress is a major environmental threat affecting crop growth and productivity. However, the molecular mechanisms associated with plant responses to heat are poorly understood. Here, we identified stress‐sensitive mutant, hts1 , in rice. HTS1 encodes thylakoid membrane‐localized β‐ketoacyl carrier protein reductase (KAR) involved de novo fatty acid biosynthesis. Phylogenetic bioinformatic analysis showed that probably originated from streptophyte algae evolutionarily conserved land plants. Thermostable predominantly expressed green tissues strongly induced by stress, but less responsive salinity, cold drought treatments. An amino substitution at A254T causes significant decrease KAR enzymatic activity and, consequently, impairs synthesis lipid metabolism especially under stress. Compared wild‐type, mutant exhibited heat‐induced higher H 2 O accumulation, larger Ca 2+ influx mesophyll cells, more damage membranes chloroplasts. Also, disrupted signaling depresses transcriptional activation of HsfA2s downstream target genes. We suggest critical for underpinning membrane stability, chloroplast integrity tolerance
SUPPLEMENTAL MATERIAL
Coming soon ....
REFERENCES (85)
CITATIONS (51)