Small Nuclear RNA Activating Complex Polypeptide 2 (SNAPC2)

Eukaryotic RNA polymerases I (pol I), II (pol II), and III (pol III) initiate RNA synthesis only in the presence of distinct sets of additional proteins, called general transcription factors (GTFs). GTFs assemble in a complex on the DNA promoter and recruit the RNA polymerase.

Sequence analysis predicted that the deduced 334-amino acid SNAPC2 is an acidic (pI of 5.7), proline-rich (13.8% of all residues) protein. Immunodepletion experiments showed that SNAPC2 is required for the transcription of both pol II- and pol III-dependent snRNA genes. Immunoblot analysis suggested that in the presence of high salt, the SNAPC subunits bind more strongly with each other than they do with TBP.