The function of RIPK4 (receptor interacting serine/threonine kinase 4, Ensembl gene identifier ENSG00000183421) is as follows. Serine/threonine protein kinase (By similarity). Required for embryonic skin development and correct skin homeostasis in adults, via phosphorylation of PKP1 and subsequent promotion of keratinocyte differentiation and cell adhesion (By similarity). It is a direct transcriptional target of TP63 (PubMed:22197488). Plays a role in NF- kappa-B activation (PubMed:12446564). {ECO:0000250|UniProtKB:Q9ERK0, ECO:0000269|PubMed:12446564, ECO:0000269|PubMed:22197488}.