Single-particle cryo-EM of the ryanodine receptor channel

Basic and applied myology

Mariah R. Baker¹  Guizhen Fan¹  Irina I. Serysheva¹ 

[1] Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, TX

关键词: Ryanodine receptor;    Membrane proteins;    Electron cryo-microscopy;    Cryospecimen preparation;    Detergents;    Amphipol;   

DOI  :  10.4081/ejtm.2015.4803

学科分类：农业科学（综合）

来源: Pagepress

【 摘 要 】

Ryanodine receptors (RyRs) are tetrameric ligand-gated Ca2+ release channels that are responsible for the increase of cytosolic Ca2+ concentration leading to muscle contraction. Our current understanding of RyR channel gating and regulation is greatly limited due to the lack of a high-resolution structure of the channel protein. The enormous size and unwieldy shape of Ca2+ release channels make X-ray or NMR methods difficult to apply for high-resolution structural analysis of the full-length functional channel. Single-particle electron cryo-microscopy (cryo-EM) is one of the only effective techniques for the study of such a large integral membrane protein and its molecular interactions. Despite recent developments in cryo-EM technologies and break-through single-particle cryo-EM studies of ion channels, cryospecimen preparation, particularly the presence of detergent in the buffer, remains the main impediment to obtaining atomic-resolution structures of ion channels and a multitude of other integral membrane protein complexes. In this review we will discuss properties of several detergents that have been successfully utilized in cryo-EM studies of ion channels and the emergence of the detergent alternative amphipol to stabilize ion channels for structure-function characterization. Future structural studies of challenging specimen like ion channels are likely to be facilitated by cryo-EM amenable detergents or alternative surfactants.

【 授权许可】

CC BY