Summary
Membrane proteins can be bulked up for structure-determination by cryo-EM by inserting designed domains, some of which can be further grown in size with predefined epitopes for antibodies and nanobodies (1,2). Other proteins for insertion include BRIL, T4 Lysozyme (widely used for GPCRs), GFP (for SGLT1 and SGLT2), flavoredoxin, xylanase, and rubredoxin ((3); they liked BRIL the best).
Figures
Ref (1)
Ref (2)
Ref (3)
See also
- De novo designed backbones can increase the size of proteins for cryo-EM structure determination
- Antibodies and nanobodies can desymmetrize proteins for cryoEM
1.
Mukherjee S, Erramilli SK, Ammirati M, Alvarez FJD, Fennell KF, Purdy MD, et al. Synthetic antibodies against BRIL as universal fiducial marks for single−particle cryoEM structure determination of membrane proteins. Nature Communications. 2020;11(1). Available from: https://doi.org/10.1038/s41467-020-15363-0
2.
Niu Y, Liu R, Guan C, Zhang Y, Chen Z, Hoerer S, et al. Structural basis of inhibition of the human SGLT2–MAP17 glucose transporter. Nature. 2021;601(7892):280–4. Available from: https://doi.org/10.1038/s41586-021-04212-9
3.
Chun E, Thompson AA, Liu W, Roth CB, Griffith MT, Katritch V, et al. Fusion Partner Toolchest for the Stabilization and Crystallization of G Protein-Coupled Receptors. Structure. 2012;20(6):967–76. Available from: https://doi.org/10.1016/j.str.2012.04.010