Transcriptome-wide N-methyladenosine profiling reveals growth-defense trade-offs in the response of rice to brown planthopper (Nilaparvata lugens) infestation.

BACKGROUND

N-Methyladenosine (mA) is a common messenger RNA (mRNA) modification that affects various physiological processes in stress responses. However, the role of mA modifications in plants responses to herbivore stress remains unclear.

RESULTS

Here, we found that an infestation of brown planthopper (Nilaparvata lugens) female adults enhanced the resistance of rice to N. lugens. The mA methylome analysis of N. lugens-infested and uninfested rice samples was performed to explore the interaction between rice and N. lugens. The mA methylation mainly occurred in genes that were actively expressed in rice following N. lugens infestation, while an analysis of the whole-genomic mRNA distribution of mA showed that N. lugens infestation caused an overall decrease in the number of mA methylation sites across the chromosomes. The mA methylation of genes involved in the mA modification machinery and several defense-related phytohormones (jasmonic acid and salicylic acid) pathways was increased in N. lugens-infested rice compared to that in uninfested rice. In contrast, mA modification levels of growth-related phytohormone (auxin and gibberellin) biosynthesis-related genes were significantly attenuated during N. lugens infestation, accompanied by the down-regulated expression of these transcripts, indicating that rice growth was restricted during N. lugens attack to rapidly optimize resource allocation for plant defense. Integrative analysis of the differential patterns of mA methylation and the corresponding transcripts showed a positive correlation between mA methylation and transcriptional regulation.

CONCLUSION

The mA modification is an important strategy for regulating the expression of genes involved in rice defense and growth during rice-N. lugens interactions. These findings provide new ideas for formulating strategies to control herbivorous pests. © 2024 Society of Chemical Industry.