Crucial regulator of the mitotic cell cycle and development. At prophase, required for dynein anchoring to the nuclear envelope important for proper centrosome-nucleus coupling. At G2/M phase, may be required for proper spindle formation and execution of cytokinesis. Probable component of the Integrator (INT) complex, a complex involved in the small nuclear RNAs (snRNA) U1 and U2 transcription and in their 3'-box-dependent processing (PubMed:23904267). Interacts with PAFAH1B1; this interaction may be required for proper recruitment of dynein complexes to the nuclear envelope at prophase. Nuclear location is required for recruitment of dynein motors to nuclear envelope at G2/M. Widely expressed. Tends to be up-regulated in seminomas compared to normal testis. RNAi in HeLa cells results in a multinucleated phenotype. Belongs to the asunder family.