#cyclins

Go, No Go

The most important decision a cell has to make is whether to divide or not. Cells must divide at the right time and in the right place to build an organism as it develops and keep it healthy. But dividing too much can lead to cancer. Molecules called cyclin dependent kinases (CDKs) are key players in the decision to divide. To find out more about their role in cell division, scientists have developed a technique for visualising the levels of CDKs in living cells using coloured fluorescent markers. By watching these markers change in a zebrafish eye (green and pink spiral in the centre of this composite image) and various developmental stages of tiny nematode worms (arranged around the outside), they’ve found that cells that still have high CDK activity after they’ve just divided are more likely to divide again, providing new insights into how this vital decision is made.

Written by Kat Arney

Image from work by Rebecca C Adikes, Abraham Q Kohrman and Michael A Q Martinez, and colleagues, Matus Lab

Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA

Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)

Published in eLife, December 2020

The role of XAL1 in the root cell dynamics underpinning root growth

Morphogenesis depends on the modulation of cell proliferation and differentiation. The reverse genetics approach of García-Cruz et al. reveals that such modulation is dynamically adjusted in response to various signals via a complex transcriptional regulatory network that mediates between such signals and cell-cycle regulation and cell-fate decisions resulting in proliferation, growth or…

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