Pectin methylesterase 31 is transcriptionally repressed by ABI5 to negatively regulate ABA-mediated inhibition of seed germination

Yang Xiang; Chongyang Zhao; Qian Li; Yingxue Niu; Yitian Pan; Guangdong Li; Yuan Cheng; Aying Zhang

doi:10.3389/fpls.2024.1336689

Pectin methylesterase 31 is transcriptionally repressed by ABI5 to negatively regulate ABA-mediated inhibition of seed germination

Front Plant Sci. 2024 Feb 2:15:1336689. doi: 10.3389/fpls.2024.1336689. eCollection 2024.

Authors

Yang Xiang¹, Chongyang Zhao¹, Qian Li¹, Yingxue Niu¹, Yitian Pan¹, Guangdong Li¹, Yuan Cheng¹, Aying Zhang^{1

2}

Affiliations

¹ College of Life Sciences, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Nanjing Agricultural University, Nanjing, China.
² Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China.

Abstract

Pectin methylesterase (PME), a family of enzymes that catalyze the demethylation of pectin, influences seed germination. Phytohormone abscisic acid (ABA) inhibits seed germination. However, little is known about the function of PMEs in response to ABA-mediated seed germination. In this study, we found the role of PME31 in response to ABA-mediated inhibition of seed germination. The expression of PME31 is prominent in the embryo and is repressed by ABA treatment. Phenotype analysis showed that disruption of PME31 increases ABA-mediated inhibition of seed germination, whereas overexpression of PME31 attenuates this effect. Further study found that ABI5, an ABA signaling bZIP transcription factor, is identified as an upstream regulator of PME31. Genetic analysis showed that PME31 functions downstream of ABI5 in ABA-mediated seed germination. Detailed studies showed that ABI5 directly binds to the PME31 promoter and inhibits its expression. In the plants, PME31 expression is reduced by ABI5 in ABA-mediated seed germination. Taken together, PME31 is transcriptionally inhibited by ABI5 and negatively regulates ABA-mediated seed germination inhibition. These findings shed new light on the mechanisms of PMEs in response to ABA-mediated seed germination.

Keywords: ABI5; PME31; abscisic acid; seed germination; transcription repression.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by National Natural Science Foundation of China (32201707), the Fundamental Research Funds for the Central Universities (KYQN2023025), Natural Science Foundation of Jiangsu Province (BK20220999), China Postdoctoral Science Foundation (2021M701739, 2023T160323), Jiangsu Funding Program for Excellent Postdoctoral Talent (2022ZB330), Open Competition Mechanism to Select the Best Candidates Fund of Jiangsu Province (JBGS[2021]012), Key Research and Development Program of Ningxia Hui Autonomous Region (2023BCF01009), and the Achievement Transformation Fund Project of Hainan Research Institute of Nanjing Agricultural University (NAUSY-CG-YB07).