CDK5 Regulatory Subunit Associated Protein 1 (CDK5RAP1)

Neuronal CDC2-like kinase, which is involved in the regulation of neuronal differentiation, is composed of a catalytic subunit, CDK5, and an activating subunit, p25NCK5A. The protein encoded by this gene binds to p25NCK5A and therefore may be involved in neuronal differentiation. Multiple transcript variants exist for this gene, but the full-length natures of only two have been determined.

Full-length Cdk5rap1 inhibited the kinase activity of the dimer. A C-terminal fragment of mammalian Cdk5rap1 bound with high affinity but was not inhibitory. Ectopic expression of Cdk5rap1 suppressed the differentiation of rat neuroblastoma cells, and expression of the C-terminal fragment had significantly less effect.