CryoEM structure of a beta3K279T GABA(A)R homomer in complex with histamine and megabody Mb25CryoEM structure of a beta3K279T GABA(A)R homomer in complex with histamine and megabody Mb25

Structural highlights

6qfa is a 10 chain structure with sequence from Helicobacter pylori G27, Homo sapiens and Lama glama. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:Electron Microscopy, Resolution 2.49Å
Ligands:, , ,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

GBRB3_HUMAN Autism;Childhood absence epilepsy. Disease susceptibility is associated with variations affecting the gene represented in this entry.

Function

GBRB3_HUMAN GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel.

Publication Abstract from PubMed

Nanobodies are popular and versatile tools for structural biology. They have a compact single immunoglobulin domain organization, bind target proteins with high affinities while reducing their conformational heterogeneity and stabilize multi-protein complexes. Here we demonstrate that engineered nanobodies can also help overcome two major obstacles that limit the resolution of single-particle cryo-electron microscopy reconstructions: particle size and preferential orientation at the water-air interfaces. We have developed and characterized constructs, termed megabodies, by grafting nanobodies onto selected protein scaffolds to increase their molecular weight while retaining the full antigen-binding specificity and affinity. We show that the megabody design principles are applicable to different scaffold proteins and recognition domains of compatible geometries and are amenable for efficient selection from yeast display libraries. Moreover, we demonstrate that megabodies can be used to obtain three-dimensional reconstructions for membrane proteins that suffer from severe preferential orientation or are otherwise too small to allow accurate particle alignment.

Megabodies expand the nanobody toolkit for protein structure determination by single-particle cryo-EM.,Uchanski T, Masiulis S, Fischer B, Kalichuk V, Lopez-Sanchez U, Zarkadas E, Weckener M, Sente A, Ward P, Wohlkonig A, Zogg T, Remaut H, Naismith JH, Nury H, Vranken W, Aricescu AR, Pardon E, Steyaert J Nat Methods. 2021 Jan;18(1):60-68. doi: 10.1038/s41592-020-01001-6. Epub 2021 Jan, 6. PMID:33408403[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Uchanski T, Masiulis S, Fischer B, Kalichuk V, Lopez-Sanchez U, Zarkadas E, Weckener M, Sente A, Ward P, Wohlkonig A, Zogg T, Remaut H, Naismith JH, Nury H, Vranken W, Aricescu AR, Pardon E, Steyaert J. Megabodies expand the nanobody toolkit for protein structure determination by single-particle cryo-EM. Nat Methods. 2021 Jan;18(1):60-68. doi: 10.1038/s41592-020-01001-6. Epub 2021 Jan, 6. PMID:33408403 doi:http://dx.doi.org/10.1038/s41592-020-01001-6

6qfa, resolution 2.49Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA