SRA

MYC proteins bind globally to active promoters and promote transcriptional elongation by RNA polymerase II (RNAPII). To identify effector proteins that mediate this function, we performed mass spectrometry on N-MYC complexes in neuroblastoma cells. The analysis shows that N-MYC forms complexes with TFIIIC, TOP2A and RAD21, a subunit of cohesin. N-MYC and TFIIIC bind to overlapping sites in thousands of RNAPII promoters and intergenic regions. TFIIIC promotes association of RAD21 with N-MYC target sites and is required for N-MYC-dependent promoter escape and pause release of RNAPII. Aurora-A competes with binding of TFIIIC and RAD21 to N-MYC in vitro and antagonizes association of TOP2A, TFIIIC and RAD21 with N-MYC during S-phase, blocking N-MYC-dependent release of RNAPII from the promoter. Inhibition of Aurora-A in S-phase restores RAD21 and TFIIIC binding to chromatin and partially restores N-MYC-dependent transcriptional elongation. We propose that complex formation with Aurora-A controls N-MYC function during the cell cycle. Overall design: DNA-binding of N-MYC and TFIIIC upon inhibition of Aurora-A, RNAPII occupancy after shRNA-mediated depletion of TFIIIC5 or in S-phase arrested SH-EP-NMYCER cells and gene expression changes after depletion of RAD21, Aurora-A and TFIIIC5 or activation of NMYC.