The snRNA-activating protein complex 43 kDa subunit (SNAP43/SNAPC1/PTF) is part of the SNAPc complex required for the transcription of both RNA polymerase II and III small-nuclear RNA genes. The SNAPc complex is composed of 5 subunits: SNAPC1, SNAPC2, SNAPC3, SNAPC4 and SNAPC5. SNAP43 is often found in OPT domain bodies, which contains several transcription factors (Oct1/PTF) and RNA transcripts, predominant in late G1 cells. OPT domain bodies localize close to the nucleolus.The synthetic peptide used to raise the antibody Cat. No. 200182 is selected from a sequence within the C-term region of human SNAP43. For blocking experiments, a 10 to 100 fold molar excess to antibody is recommended.