The protein encoded by this gene is a member of the nephrin-like protein family. These proteins are expressed in fetal and adult brain, and also in podocytes of kidney glomeruli. The cytoplasmic domains of these proteins interact with the C-terminus of podocin, also expressed in the podocytes, cells involved in ensuring size- and charge-selective ultrafiltration. Mutations in this gene are associated with mental retardation autosomal dominant type 4 (MRD4). Alternatively spliced transcript variants encoding different isoforms have been found for this gene.