University of Cambridge > Talks.cam > Biophysical Seminars > Insights into unfolded protein states and GPCR function by solution NMR

Insights into unfolded protein states and GPCR function by solution NMR

Add to your list(s) Download to your calendar using vCal

If you have a question about this talk, please contact ma505.

We use extensively residual dipolar coupling, paramagnetic labeling, hydrogen bond scalar couplings and other NMR and non-NMR parameters to characterize unfolded protein states in a quantitative manner [1-6]. Thus we have generated a minimal structural ensemble of urea-denatured ubiquitin by constrained structure calculations. The ensemble reveals about 10 % native-like local structure in parts of the molecule on the background of long-range Gaussian chain behavior, thereby resolving Levinthal’s paradox. Recent orthogonal single molecule FRET data show excellent agreement to this ensemble. Furthermore, we have obtained atomic details of the pressure-assisted, cold-denatured state of ubiquitin by high-resolution NMR techniques. This state has structural propensities, which are very similar to ubiquitin’s alcohol-denatured (A-) state.

G protein-coupled receptors (GPCRs) are physiologically important transmembrane signaling proteins that trigger intracellular responses upon binding of extracellular ligands. Despite recent breakthroughs in GPCR crystallography, the details of ligand-induced signal transduction are not well understood due to missing dynamical information. We have recently shown [7] that receptor motions can be followed at virtually any backbone site in a thermostabilized mutant of the turkey 1-adrenergic receptor. I will discuss insights from NMR on ligand recognition, thermostabilization, signal transduction and G-protein binding as well as recently developed strategies for economic isotope labeling in insect cells [8].

References

[1] Huang, J.-R., Grzesiek, S., J. Am. Chem. Soc. 2010, 132, 694–705.

[2] Nisius, L., Grzesiek, S., Nat Chem 2012, 4, 711–717.

[3] Vajpai, N., Nisius, L., Wiktor, M., Grzesiek, S., Proc. Natl. Acad. Sci. USA 2013 , 110, E368 –76.

[4] Leung, H. T. A., Bignucolo, O., Aregger, R., Dames, S. A., Mazur, A., Bernèche, S., Grzesiek, S., J. Chem. Theory Comput. 2016, 12, 383–394.

[5] Bignucolo, O., Leung, H. T. A., Grzesiek, S., Bernèche, S., J. Am. Chem. Soc. 2015, 137, 4300–4303.

[6] Aznauryan, M., Delgado, L., Soranno, A., Nettels, D., Huang, J.-R., Labhardt, A. M., Grzesiek, S., Schuler, B., Proc. Natl. Acad. Sci. USA 2016 , 113, E5389 –E5398.

[7] Isogai, S., Deupi, X., Opitz, C., Heydenreich, F. M., Tsai, C.-J., Brueckner, F., Schertler, G. F. X., Veprintsev, D. B., Grzesiek, S., Nature 2016, 530, 237–241.

[8] Opitz, C., Isogai, S., Grzesiek, S., J. Biomol. NMR 2015 , 62, 373–385.

This talk is part of the Biophysical Seminars series.

Tell a friend about this talk:

This talk is included in these lists:

Note that ex-directory lists are not shown.

 

© 2006-2024 Talks.cam, University of Cambridge. Contact Us | Help and Documentation | Privacy and Publicity