Timing mechanisms: insights from comparative neural differentiation systems.

Temporal control is central to deploy and coordinate genetic programs during development. At present, there is limited understanding of the molecular mechanisms that govern the duration and speed of developmental processes. Timing mechanisms may run in parallel and/or interact with each other to integrate temporal signals throughout the organism. In this piece, we consider findings on the extrinsic control of developmental tempo and discuss the intrinsic roles of cell cycle, metabolic rates, protein turnover, and post-transcriptional mechanisms in the regulation of tempo during neural development.