Caste-specific gene expression underlying the differential adult brain development in the honeybee Apis mellifera

• Autor(a) principal: de Paula Junior, D. E.
• Data de Publicação: 2021
• Outros Autores: de Oliveira, M. T., Bruscadin, J. J., Pinheiro, D. G. [UNESP], Bomtorin, A. D., Coelho Júnior, V. G., Moda, L. M.R., Simões, Z. L.P., Barchuk, A. R.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1111/imb.12671; http://hdl.handle.net/11449/205353
• topic: brain development; diphenism; honey bee; nervous system; pupa; queen; worker

Apis mellifera adult workers feature more developed key brain regions than queens, which allows them to cope with the broad range of duties they need to perform in a colony. However, at the end of larval development, the brain of queens is largely more developed than that of workers. Major morphogenetic changes take place after metamorphosis that shift caste-specific brain development. Here, we tested the hypothesis that this phenomenon is hormonally governed and involves differential gene expression. Our molecular screening approach revealed a set of differentially expressed genes in Pp (first pharate-adult phase) brains between castes mainly coding for tissue remodelling and energy-converting proteins (e.g. hex 70a and ATPsynβ). An in-depth qPCR analysis of the transcriptional behaviour during pupal and pharate-adult developmental stage in both castes and in response to artificially augmented hormone titres of 18 genes/variants revealed that: i. subtle differences in hormone titres between castes might be responsible for the differential expression of the EcR and insulin/insulin-like signalling (IIS) pathway genes; ii. the morphogenetic activity of the IIS in brain development must be mediated by ILP-2, iii. which together with the tum, mnb and caspase system, can constitute the molecular effectors of the caste-specific opposing brain developmental trajectories.