A neural m⁶A pathway regulates behavioral aggregation in migratory locusts

Area of Science:

• Epigenetics and Molecular Biology
• Insect Behavior and Ecology
• RNA Modifications

Background:

• RNA N⁶-methyladenosine (m⁶A) is the most prevalent mRNA modification.
• m⁶A is known to influence various biological processes, including gene expression and development.
• The role of m⁶A in modulating insect aggregation behaviors has not been previously investigated.

Purpose of the Study:

• To investigate the function of the m⁶A pathway in regulating aggregation behaviors in the migratory locust, *Locusta migratoria*.
• To characterize the expression patterns and functional roles of key m⁶A methyltransferase (METTL3, METTL14) and demethylase (ALKBH5) components in locusts.

Main Methods:

• Molecular and physiological characterization of m⁶A pathway components (METTL3, METTL14, ALKBH5) in *Locusta migratoria*.
• Analysis of gene expression in response to crowding and isolation.
• Individual knockdown experiments using RNA interference (RNAi) to assess behavioral changes.
• Global transcriptome profiling to understand gene expression regulation by m⁶A.

Main Results:

• METTL3, METTL14, and ALKBH5 were predominantly expressed in the locust brain and responded to social conditions (crowding/isolation).
• Knockdown of METTL3 or METTL14 enhanced locust movement and attraction to conspecifics.
• Knockdown of ALKBH5 induced a shift towards solitary phase behaviors.
• m⁶A modification was found to regulate gene expression networks crucial for fine-tuning aggregation behaviors.

Conclusions:

• The m⁶A pathway plays a critical role in modulating aggregation behaviors in migratory locusts.
• Specific m⁶A pathway components differentially regulate transitions between gregarious and solitary phases.
• This study provides the first in vivo evidence for the significant involvement of RNA m⁶A modification in insect social behavior.