Reducing the risk of rearrangement
As lymphocytes develop, they rearrange their antigen receptor genes and proliferate extensively, potentially putting their genomes at risk. Galloway et al. found that two RNA-binding proteins, ZFP36L1 and ZFP36L2, ensure careful entry and exit into the cell cycle. This helps developing B lymphocytes maintain their genomic integrity. Mice deficient in ZFP36L1 and ZFP36L2 exhibited a profound block in B cell development. ZFP36L1 and ZFP36L2 suppress mRNAs that help B cells progress through the cell cycle, ensuring that cells can enter quiescence and keep their genomes safe when they undergo the risky process of rearranging their antigen receptors.
Science, this issue p. 453