The function of ATN1 (atrophin 1, Ensembl gene identifier ENSG00000111676) is as follows. Transcriptional corepressor. Recruits NR2E1 to repress transcription. Promotes vascular smooth cell (VSMC) migration and orientation (By similarity). Corepressor of MTG8 transcriptional repression. Has some intrinsic repression activity which is independent of the number of poly-Gln (polyQ) repeats. {ECO:0000250|UniProtKB:O35126, ECO:0000269|PubMed:10085113, ECO:0000269|PubMed:10973986}.