Back to the basics? Transcriptomics offers integrative insights into the role of space, time and the environment for gene expression and behaviour

Fuelled by the ongoing genomic revolution, broadscale RNA expression surveys are fast replacing studies targeting one or a few genes to understand the molecular basis of behaviour. Yet, the timescale of RNA-sequencing experiments and the dynamics of neural gene activation are insufficient to drive real-time switches between behavioural states. Moreover, the spatial, functional and transcriptional complexity of the brain (the most commonly targeted tissue in studies of behaviour) further complicates inference. We argue that a Central Dogma-like 'back-to-basics' assumption that gene expression changes cause behaviour leaves some of the most important aspects of gene-behaviour relationships unexplored, including the roles of environmental influences, timing and feedback from behaviour-and the environmental shifts it causes-to neural gene expression. No perfect experimental solutions exist but we advocate that explicit consideration, exploration and discussion of these factors will pave the way toward a richer understanding of the complicated relationships between genes, environments, brain gene expression and behaviour over developmental and evolutionary timescales.

Automated summary

Driven by the genomic revolution, broadscale RNA expression surveys are replacing studies targeting individual genes to understand behavior. However, RNA-sequencing experiments and neural gene activation dynamics cannot facilitate real-time switches between behavioral states. The complexity of the brain further complicates inference on gene-behavior relationships. Explicit consideration, exploration, and discussion of factors such as environmental influences, timing, and feedback from behavior are crucial for a better understanding of the relationships between genes, environments, brain gene expression, and behavior over developmental and evolutionary timescales.