An error was published in Development137, 3763-3774.

On p. 3764, the Id2a morpholino sequences were incorrect. The correct sequences are:

Id2a-MO, 5′-GCCTTCATGTTGACAGCAGGATTTC3′; and Id2a-MM, 5′-GCGTTGATGTTCACAGCACGAATTC-3′.

The nucleotides in bold differ from the published ones.

The authors apologise to readers for this mistake.