Validated Determination of NRG1 Ig-like Domain Structure by Mass Spectrometry Coupled with Computational Modeling

Abolhasani Khaje, N.; Eletsky, A.; Biehn, S. E.; Mobley, C. K.; Rogals, M. J.; Kim, Y.; Mishra, S. K.; Doerksen, R. J.; Lindert, S.; Prestegard, J.; Sharp, J. S.

doi:10.1101/2021.12.13.472484

bioRxiv · 10.1101/2021.12.13.472484

Validated Determination of NRG1 Ig-like Domain Structure by Mass Spectrometry Coupled with Computational Modeling

Abolhasani Khaje, N.·Eletsky, A.·Biehn, S. E.·Mobley, C. K.·Rogals, M. J.·Kim, Y.·Mishra, S. K.·Doerksen, R. J.·Lindert, S.·Prestegard, J.·Sharp, J. S.

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Abstract

High resolution hydroxyl radical protein footprinting (HR-HRPF) is a mass spectrometry-based method that measures the solvent exposure of multiple amino acids in a single experiment, offering constraints for experimentally-informed computational modeling. HR-HRPF-based modeling has previously been used to accurately model the structure of proteins of known structure, but the technique has never been used to determine the structure of a protein of unknown structure leaving questions of unintentional bias and applicability to unknown structures unresolved. Here, we present the use of HR-HRPF-based modeling to determine the structure of the Ig-like domain of NRG1, a protein with no close homolog of known structure. Independent determination of the protein structure by both HR-HRPF-based modeling and heteronuclear NMR was carried out, with results compared only after both processes were complete. The HR-HRPF-based model was highly similar to the lowest energy NMR model, with a backbone RMSD of 1.6 [A]. To our knowledge, this is the first use of HR-HRPF-based modeling to determine a previously uncharacterized protein structure.

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Abolhasani Khaje, N., Eletsky, A., Biehn, S. E., Mobley, C. K., Rogals, M. J., Kim, Y., Mishra, S. K., Doerksen, R. J., Lindert, S., Prestegard, J., Sharp, J. S.. 2021-12-14. Validated Determination of NRG1 Ig-like Domain Structure by Mass Spectrometry Coupled with Computational Modeling. https://doi.org/10.1101/2021.12.13.472484

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