Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 May;48(5):3391-3405.
doi: 10.1111/pce.15359. Epub 2025 Jan 5.

HTT1, a Stearoyl-Acyl Carrier Protein Desaturase Involved Unsaturated Fatty Acid Biosynthesis, Affects Rice Heat Tolerance

Xiaobo Zhang  1   2 , Xuefei Zhang  1 , Yao Fu  1 , Yixin Cui  3 , Nai Wu  4 , Yangyang Li  1 , Zhenglin Yang  1 , Changwei Zhang  1 , Hongyuan Song  2 , Guanghua He  1 , Xianchun Sang  1
Affiliations

HTT1, a Stearoyl-Acyl Carrier Protein Desaturase Involved Unsaturated Fatty Acid Biosynthesis, Affects Rice Heat Tolerance

Xiaobo Zhang et al. Plant Cell Environ. 2025 May.

Abstract

Elucidating the mechanisms underlying heat tolerance in rice (Oryza Sativa. L) is vital for adapting this crop to rising global temperature while increasing yields. Here, we identified a rice mutant, high temperature tolerance 1 (htt1), with high survival rates under heat stress. HTT1 encodes a chloroplast-localized stearoyl-acyl carrier protein (ACP) desaturase involved in the biosynthesis of unsaturated fatty acids, converting C18:0 to C18:1 fatty acid. Overexpression and knockout rice lines provided evidence that HTT1 negatively regulates the response to heat stress. In the htt1 mutant, a G-to-A base substitution in HTT1 impairs unsaturated fatty acid biosynthesis, remodelling the lipid content of cellular membranes and in particular increasing diglyceride contents, which improves membrane stability under heat stress. HTT1 was differentially expressed in all tissues analyzed and was inhibited by heat. Yeast one-hybrid and dual-luciferase reporter assays showed that OsHsfA2d binds to the promoter of HTT1, inhibiting its expression. Different HTT1 alleles were identified between the two Asian cultivated rice subspecies, indica and japonica, potentially facilitating their adaptation to different environmental temperature. Taken together, these findings demonstrate that HTT1 is a previously unidentified negative regulator of heat tolerance and a potential target gene for the improvement of heat adaptability in rice.

Keywords: OsHsfA2d; high temperature tolerance 1 (HTT1); membrane stability; rice (Oryza sativa. L); unsaturated fatxty acids.

PubMed Disclaimer

References

    1. Albertos, P., G. Dündar, P. Schenk, et al. 2022. “Transcription Factor BES1 Interacts With HSFA1 to Promote Heat Stress Resistance of Plants.” EMBO Journal 41, no. 3: e108664.
    1. Chen, F., G. Dong, F. Wang, et al. 2021. “A β‐Ketoacyl Carrier Protein Reductase Confers Heat Tolerance Via the Regulation of Fatty Acid Biosynthesis and Stress Signaling in Rice.” New Phytologist 232, no. 2: 655–672.
    1. Chen, S., H. Cao, B. Huang, et al. 2022. “The WRKY10‐VQ8 Module Safely and Effectively Regulates Rice Thermotolerance.” Plant, Cell & Environment 45, no. 7: 2126–2144.
    1. Chen, Z., W. Jasinska, M. Ashraf, et al. 2023. “Lipidomic Insights Into the Response of Arabidopsis Sepals to Mild Heat Stress.” Abiotech 4, no. 3: 224–237.
    1. Cheng, Q., Y. Zhou, Z. Liu, et al. 2015. “An Alternatively Spliced Heat Shock Transcription Factor, OsHSFA2dI, Functions in the Heat Stress‐Induced Unfolded Protein Response in Rice.” Plant Biology 17, no. 2: 419–429.

LinkOut - more resources