Biased gene expression in early honeybee larval development.

Area of Science:

• Entomology
• Developmental Biology
• Genomics

Background:

• Honeybee (Apis mellifera) caste determination is nutritionally regulated.
• Larval nutrition dictates development into queens or workers with distinct physiology and lifespan.

Purpose of the Study:

• To investigate the gene expression patterns underlying honeybee larval caste differentiation.
• To identify early molecular events that establish distinct queen and worker developmental trajectories.

Main Methods:

• Comprehensive gene expression atlas generation throughout honeybee larval development.
• RNA interference (RNAi) to assess gene function in caste differentiation.

Main Results:

• Significant gene expression differences between queen and worker larvae observed as early as 6 hours post-hatching.
• Queen-destined larvae show early upregulation of transcription/translation genes, shifting to energy metabolism genes later.
• Hexamerin 70b identified as a gene playing a role in caste differentiation.
• Differential gene splicing observed in both castes, with specific variants linked to caste determination.

Conclusions:

• Honeybee caste development involves an initial, flexible phase influenced by nutrition, followed by a commitment phase.
• Early gene expression biases are critical for establishing long-term caste-specific developmental trajectories.