Unc-5 Homolog B (UNC5B)

UNC5B belongs to a family of netrin-1 receptors thought to mediate the chemorepulsive effect of netrin-1 on specific axons. The deduced 934-amino acid protein has a calculated molecular mass of about 103 kD. UNC5B contains 2 immunoglobulin domains and 2 thrombospondin type-1 motifs in its N-terminal extracellular half, followed by a transmembrane domain, a ZU-5 domain, a DCC-binding domain, and a C-terminal death domain.

UNC5B shares 54% amino acid identity with UNC5A, 63% identity with UNC5C, and 91% identity with rat Unc5h2. Northern blot analysis detected a major 7.5-kb transcript expressed at high levels in lung, brain, and hematopoietic and immune tissues, with lower levels in heart and kidney.