Dynamic duo: Kir6 and SUR in K_ATP channel structure and function

Area of Science:

• Biochemistry
• Molecular Biology
• Structural Biology

Background:

• ATP-sensitive potassium (KATP) channels are crucial regulators of cell activity, linking cellular energy status to membrane potential.
• These channels are octameric complexes composed of four Kir6 pore-forming subunits and four regulatory sulfonylurea receptor (SUR) subunits.
• SUR, an ATP-binding cassette (ABC) protein homolog, is vital for KATP channel expression and function, mediating metabolic control.

Approach:

• This review synthesizes decades of functional data on Kir6 and SUR subunits.
• It correlates this extensive functional knowledge with recent advancements in KATP channel structural biology, particularly cryo-electron microscopy (cryo-EM) structures.
• The focus is on elucidating the structure-function relationships within the KATP channel complex.

Key Points:

• Recent cryo-EM structures provide unprecedented atomic-level insights into KATP channel architecture.
• The integration of functional data with structural information is key to understanding KATP channel regulation.
• This approach facilitates a deeper comprehension of how SUR subunits modulate Kir6 channel activity in response to metabolic cues.

Conclusions:

• Correlating functional data with cryo-EM structures enhances our understanding of KATP channel mechanisms.
• This integrated approach is essential for advancing research on KATP channels and their clinical relevance.
• Future studies will likely build upon these structural insights to explore therapeutic interventions targeting KATP channels.