The protein encoded by this gene is a scaffold protein and a regulator for three different kinases involved in proinflammatory signaling. The encoded protein can bind NF-kappa-B-inducing kinase and I-kappa-B kinases through separate domains and assemble them into an active kinase complex. Mutations in this gene have been associated with familial dysautonomia. Alternative splicing results in multiple transcript variants encoding different isoforms.