Regulator subunit of pancreatic ATP-sensitive potassium channel (KATP), playing a major role in the regulation of insulin release. In pancreatic cells, it forms KATP channels with KCNJ11; KCNJ11 forms the channel pore while ABCC8 is required for activation and regulation. {ECO:0000269|PubMed:24814349, ECO:0000269|PubMed:25720052, ECO:0000269|PubMed:29286281, ECO:0000269|PubMed:34815345}. This is the function of ABCC8 (ATP binding cassette subfamily C member 8, ENSG00000006071).