Component of the integrator complex, a multiprotein complex that terminates RNA polymerase II (Pol II) transcription in the promoter-proximal region of genes (PubMed:33243860, PubMed:34004147, PubMed:39504960). The integrator complex provides a quality checkpoint during transcription elongation by driving premature transcription termination of transcripts that are unfavorably configured for transcriptional elongation: the complex terminates transcription by (1) catalyzing dephosphorylation of the C-terminal domain (CTD) of Pol II subunit POLR2A and SUPT5H/SPT5, (2) degrading the exiting nascent RNA transcript via endonuclease activity and (3) promoting the release of Pol II from bound DNA (PubMed:33243860, PubMed:34004147, PubMed:38570683, PubMed:39504960). The integrator complex is also involved in terminating the synthesis of non-coding Pol II transcripts, such as enhancer RNAs (eRNAs), small nuclear RNAs (snRNAs), telomerase RNAs and long non-coding RNAs (lncRNAs) (PubMed:16239144). Within the integrator complex, INTS6 acts as a molecular adapter that promotes assembly of protein phosphatase 2A (PP2A) subunits to the integrator core complex, promoting recruitment of PP2A to transcription pause- release checkpoint (PubMed:33243860, PubMed:34004147). Mediates recruitment of cytoplasmic dynein to the nuclear envelope, probably as component of the integrator complex (PubMed:23904267). May have a tumor suppressor role; an ectopic expression suppressing tumor cell growth (PubMed:15254679, PubMed:16239144). {ECO:0000269|PubMed:15254679, ECO:0000269|PubMed:16239144, ECO:0000269|PubMed:23904267, ECO:0000269|PubMed:33243860, ECO:0000269|PubMed:34004147, ECO:0000269|PubMed:38570683, ECO:0000269|PubMed:39504960}. This is the function of INTS6 (integrator complex subunit 6, ENSG00000102786).