Trafficking Protein, Kinesin Binding 1 (TRAK1)

By sequencing clones obtained from a size-fractionated fetal brain cDNA library, Kikuno et al. (1999) cloned KIAA1042. The deduced protein contains 953 amino acids. RT-PCR ELISA detected high expression of OIP106 in spinal cord and moderate expression in all other tissues and specific brain regions examined. By searching a sequence database for homologs of rat Oip98 (ALS2CR3), Iyer et al. (2003) identified KIAA1042, which they designated OIP106. OIP106 contains coiled-coil domains. Confocal and electron microscopy showed that OIP106 colocalized with RNA polymerase II in nuclear puncta in HeLa cells. In vitro translation synthesized a protein with an apparent molecular mass of about 115 kD by SDS/PAGE. Western blot analysis detected a 115-kD OIP106 protein in HeLa cell lysates.