A cell-autonomous timer drives the wave pattern of the segmentation clock

Andrew Oates
School of Life Sciences

Rhythmic and sequential segmentation of the vertebrate body relies on the segmentation clock, a multi-cellular oscillating genetic network. The clock is visible as tissue-level kinematic waves of gene expression that arrest at the position of each forming segment. I will show that the cellular oscillatory dynamics underlying the hallmark wave pattern are reproduced autonomously by single cells in culture. We compare these autonomous dynamics to those observed in individual cells imaged in the embryo as they transition through the segmentation clock until somite formation. A simple physical description of a clock controlled by a noisy cell-intrinsic timer captures both these in vitro and in vivo cellular dynamics. We propose that a cell-intrinsic timer drives the oscillatory dynamics that generate the wave pattern, while extrinsic factors present in the embryo tune this timer’s duration and precision. Our findings introduce cell-intrinsic timing as a new mechanism driving segmentation clock patterning.