Based on limited published evidence, WDR5B is a nuclear protein that plays a role in retinal pigment epithelial (RPE) cell proliferation 1. Loss of WDR5B impairs cell growth and increases non-viable cells in proliferating RPE cultures, suggesting an essential function in cell viability 1. WDR5B may function as a substrate receptor for CUL4-DDB1 ubiquitin E3 ligase complex. Unlike its homolog WDR5, WDR5B shows low expression in pluripotent cells but is upregulated during neural differentiation, with minimal enrichment at established WDR5 binding sites, indicating divergent biological properties 1. WDR5B expression has been associated with brain structural features in cognitive decline studies 2.