Sulfonylurea receptor 1 subunit of the KATP channel (SUR1)

Sulfonylurea receptor 1 (SUR1) is the regulatory subunit of the pancreatic ATP-sensitive potassium channel (KATP channel), an octameric complex comprising four inward-rectifier potassium channel Kir6.2 subunits and four SUR1 subunits[1][2][6]. SUR1 belongs to the ATP-binding cassette (ABC) transporter family, but it does not transport a substrate; instead, it modulates the gating of the channel complex by sensing intracellular nucleotides and binding pharmacologic agents, such as sulfonylureas and channel openers[1][2]. In pancreatic β-cells, SUR1/Kir6.2 channels couple cellular energy status to insulin secretion, playing a central role in metabolic homeostasis[6]. Mutations in the ABCC8 gene encoding SUR1 cause disorders like congenital hyperinsulinism or neonatal diabetes. SUR1 is also expressed in cardiac and some neuronal tissues, where it contributes to cardiac protection under metabolic stress and possibly to pathologies if dysregulated[4][5].

Other names

ABCC8Sulfonylurea receptor 1SUR1ATP-binding cassette sub-family C member 8

Sulfonylureas and glinides: bind SUR1 and inhibit KATP channel activity, causing depolarization of the cell membrane and stimulating insulin release[6][4]. - Diazoxide: binds and opens KATP channels via SUR1, hyperpolarizing the membrane and inhibiting insulin release[4].