N6-methyladenine DNA modification modulates pathogen virulence in nematodes

D Dadong Dai (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) S Shurong Zhang (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) B Boyan Hu (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) Y Yayi Zhou (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) S Simeng Cui (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) J Jia Sun (National Medical Products Administration Key Laboratory for Research and Evaluation of Drug Metabolism and Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University) Y Yali Zhang X Xueyu Wang (College of Sciences) S Shahid Siddique (Department of Entomology and Nematology, University of California) D Dexin Bo (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) M Min Zhang V Valerie M. Williamson (Department of Plant Pathology, University of California) H Haozhe Yao (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) X Xinya Duan (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) W Wentao Wu D Donghai Peng (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) J Jinshui Zheng (National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University) M Ming Sun

Abstract

Understanding the global regulatory mechanisms that control pathogen virulence gene expression is essential for elucidating the molecular basis of pathogenicity. N6-methyladenine (6 mA) plays a crucial role in regulating gene expression in response to various environmental stresses; however, its role in pathogen virulence remains largely unexplored. Here, we report the widespread occurrence of 6 mA across 17 nematode isolates and map its genomic landscape in six notorious agriculturally important pathogen root-knot nematodes (RKNs). We demonstrated that 6 mA is characterized by a conserved GAG motif across nematodes, but exhibits species-specific distribution patterns and distinct effects on gene expression. In particular, its enrichment in transposable elements (TEs) differs between polyploid and diploid nematodes, suggesting lineage-specific epigenetic regulation potentially associated with polyploidy. We further identified two functional 6 mA demethylases, MiNMAD-1 and MiNMAD-2, and confirmed their catalytic activity and active sites. Host-induced gene silencing (HIGS) of minmad-1 significantly increased plant resistance to three polyploid RKN species. A detailed functional analysis revealed that minmad-1 knockdown broadly affected gene expression during the parasitic stage, including genes involved in virulence, thereby reducing nematode infectivity. Together, our findings suggest 6 mA demethylase as a key epigenetic regulator of RKNs’ virulence, providing new insights into nematode biology and offering promising targets for the development of sustainable control strategies.

Article Details

Volume / Issue Vol. 123, Issue 10
Published March 10, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (18)

D

Dadong Dai

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

S

Shurong Zhang

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

B

Boyan Hu

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

Y

Yayi Zhou

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

S

Simeng Cui

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

J

Jia Sun

National Medical Products Administration Key Laboratory for Research and Evaluation of Drug Metabolism and Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University

Y

Yali Zhang

X

Xueyu Wang

College of Sciences

S

Shahid Siddique

Department of Entomology and Nematology, University of California

D

Dexin Bo

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

M

Min Zhang

V

Valerie M. Williamson

Department of Plant Pathology, University of California

H

Haozhe Yao

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

X

Xinya Duan

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

W

Wentao Wu

D

Donghai Peng

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

J

Jinshui Zheng

National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University

M

Ming Sun