The C-terminus of Kv7 channels: a multifunctional module

Area of Science:

• Molecular Biology
• Neuroscience
• Cardiology

Background:

• Kv7 (KCNQ) channels are vital for neuronal and cardiac excitability.
• Mutations in Kv7 genes cause neurological and cardiovascular disorders like epilepsy and long QT syndrome.
• Kv7 channels possess unique structural and functional C-terminal domains.

Purpose of the Study:

• To provide an overview of the structural and functional attributes of the Kv7 channel C-terminus.
• To highlight current insights and unresolved questions regarding this domain.
• To elucidate the role of the C-terminus in channel function and disease.

Main Methods:

• Review of existing literature on Kv7 channel structure and function.
• Analysis of structural domains within the Kv7 C-terminus.
• Correlation of mutations with functional and structural defects.

Main Results:

• The Kv7 C-terminus features distinct proximal and distal regions with specific functions.
• The proximal region binds calmodulin, influencing channel gating, folding, and trafficking.
• The distal region mediates tetramerization via coiled-coil structures.

Conclusions:

• The Kv7 C-terminal domain is a multimodular structure essential for channel assembly, gating, and trafficking.
• Dysfunction in the C-terminus, particularly calmodulin binding, contributes to epilepsy and long QT syndrome.
• The C-terminus acts as a scaffold for signaling protein interactions.