N6-methyladenosine modification of RNA controls dopamine synthesis to influence labour division in ants

Abstract

The N⁶-methyladenosine (m⁶A) modification of RNA has been reported to remodel gene expression in response to environmental conditions; however, the biological role of m⁶A in social insects remains largely unknown. In this study, we explored the role of m⁶A in the division of labour by worker ants (Solenopsis invicta). We first determined the presence of m⁶A in RNAs from the brains of worker ants and found that m⁶A methylation dynamics differed between foragers and nurses. Depletion of m⁶A methyltransferase or chemical suppression of m⁶A methylation in foragers resulted in a shift to 'nurse-like' behaviours. Specifically, mRNAs of dopamine receptor 1 (Dop1) and dopamine transporter (DAT) were modified by m⁶A, and their expression increased dopamine levels to promote the behavioural transition from foragers to nurses. The abundance of Dop1 and DAT mRNAs and their stability were reduced by the inhibition of m⁶A modification caused by the silencing of Mettl3, suggesting that m⁶A modification in worker ants modulates dopamine synthesis, which regulates labour division. Collectively, our results provide the first example of the epitranscriptomic regulation of labour division in social insects and implicate m⁶A regulatory mechanism as a potential novel target for controlling red imported fire ants.

Keywords: Solenopsis invicta; N6‐methyladenosine; RNA methylation; dopamine; labour division; social insects.