The E3 ubiquitin ligase RNF220 maintains hindbrain expression patterns through regulation of WDR5 stability.

The spatial and temporal linear expression of genes establishes a regional code, which is crucial for the antero-posterior (A-P) patterning, segmentation, and neuronal circuit development of the hindbrain. RNF220, an E3 ubiquitin ligase, is widely involved in neural development via targeting of multiple substrates. Here, we found that the expression of genes in the pons was markedly up-regulated at the late developmental stage (post-embryonic day E15.5) in and mouse embryos. Single-nucleus RNA sequencing (RNA-seq) analysis revealed different de-repression profiles in different groups of neurons, including the pontine nuclei (PN). The pattern was disrupted and the neural circuits were affected in the PN of mice. We showed that this phenomenon was mediated by WDR5, a key component of the TrxG complex, which can be polyubiquitinated and degraded by RNF220. Intrauterine injection of WDR5 inhibitor (WDR5-IN-4) and genetic ablation of in mice largely recovered the de-repressed expression pattern in the hindbrain. In P19 embryonal carcinoma cells, the retinoic acid-induced expression was further stimulated by knockdown, which can also be rescued by knockdown. In short, our data suggest a new role of RNF220/WDR5 in pattern maintenance and pons development in mice.