Purification of a novel RECQL5-SWI/SNF-RNAPII super complex.

RecQ helicases are members of an evolutionary conserved family of DNA helicases. They are homologous to the RecQ helicase of E. coli, the founding member of the family. These enzymes include gene products of disease-causing genes in Bloom, Werner, and Rothmund-Thomson syndrome. To date, these proteins have been implicated in many aspects of DNA metabolism, including DNA replication, repair, and recombination. We reported here that RECQL5, a newer member of the human RecQ helicase family, physically interacts with SWI/SNF complex and RNAPII core complex within the context of a super complex. RECQL5 was detected in the RNAPII holoenzyme but not in purified RNAPII core complex. Together, these data link RECQL5 to the assembly of the RNAPII transcription machinery and suggest that this helicase may have a regulatory role in RNAPII transcription or an RNAPII-related process or processes.