MAPK20-mediated ATG6 phosphorylation is critical for pollen development in Solanum lycopersicum L

Yu Wang; Dongling Xie; Xuelian Zheng; Mingyue Guo; Zhenyu Qi; Ping Yang; Jingquan Yu; Jie Zhou

doi:10.1093/hr/uhae069

MAPK20-mediated ATG6 phosphorylation is critical for pollen development in Solanum lycopersicum L

Hortic Res. 2024 Mar 6;11(5):uhae069. doi: 10.1093/hr/uhae069. eCollection 2024 May.

Authors

Yu Wang¹, Dongling Xie¹, Xuelian Zheng¹, Mingyue Guo¹, Zhenyu Qi^{2

3}, Ping Yang³, Jingquan Yu^{1

2

4

5}, Jie Zhou^{1

2

6

4

5}

Affiliations

¹ Department of Horticulture, Zhejiang University, Hangzhou 310058, China.
² Hainan Institute, Zhejiang University, Sanya 572000, China.
³ Agricultural Experiment Station, Zhejiang University, Hangzhou 310058, China.
⁴ Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Hangzhou 310058, China.
⁵ Key Laboratory of Horticultural Plants Growth, Development and Quality Improvement, Ministry of Agriculture and Rural Affairs, Hangzhou 310058, China.
⁶ Shandong (Linyi) Institute of Modern Agriculture, Zhejiang University, Linyi 276000, China.

Abstract

In flowering plants, male gametogenesis is tightly regulated by numerous genes. Mitogen-activated protein kinase (MAPK) plays a critical role in plant development and stress response, while its role in plant reproductive development is largely unclear. The present study demonstrated MAPK20 phosphorylation of ATG6 to mediate pollen development and germination in tomato (Solanum lycopersicum L.). MAPK20 was preferentially expressed in the stamen of tomato, and mutation of MAPK20 resulted in abnormal pollen grains and inhibited pollen viability and germination. MAPK20 interaction with ATG6 mediated the formation of autophagosomes. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis showed that ATG6 was phosphorylated by MAPK20 at Ser-265. Mutation of ATG6 in wild-type (WT) or in MAPK20 overexpression plants resulted in malformed and inviable pollens. Meanwhile, the number of autophagosomes in mapk20 and atg6 mutants was significantly lower than that of WT plants. Our results suggest that MAPK20-mediated ATG6 phosphorylation and autophagosome formation are critical for pollen development and germination.