Evaluation Summary:
This manuscript is of interest to individuals working on genome stability and B lymphocyte development. Using knockouts for the genes encoding the structure-selective endonucleases GEN1 and MUS81 in mice, the authors show that the absence of both proteins is incompatible with embryonic development, with selective loss in mature B-cells inhibiting germinal center formation. This is the first study of these enzymes in an organismic context and in primary cells, revealing insight into the in vivo consequences of loss of MUS81 and GEN1 functions not previously accessible through studies in cultured cells.
(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 agreed to share their name with the authors.)