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bioRxiv · 10.1101/2020.06.29.171512

Functional solubilisation of the β2-adrenoceptor (β2AR) using Diisobutylene maleic acid (DIBMA).

Harwood, C. R.·Sykes, D. A.·Hoare, B.·Heydenreich, F. M.·Uddin, R.·Poyner, D. R.·Briddon, S. J.·Veprintsev, D. B.
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Abstract

The β2-adrenoceptor (β2AR) is a well-established target in asthma and a prototypical GPCR for biophysical studies. Solubilisation of membrane proteins has classically involved the use of detergents. However, the detergent environment differs from the native membrane environment and often destabilises membrane proteins. Use of amphiphilic copolymers is a promising strategy to solubilise membrane proteins within their native lipid environment in the complete absence of detergents. Here we show the isolation of the β2AR in the polymer Diisobutylene maleic acid (DIBMA). We demonstrate that β2AR remains functional in the DIBMA lipid particle (DIBMALP) and shows improved thermal stability compared to the n-Dodecyl-β-D-Maltopyranoside (DDM) detergent solubilised β2AR. This unique method of extracting β2AR offers significant advantages over previous methods routinely employed such as the introduction of thermostabilising mutations and the use of detergents, particularly for functional biophysical studies.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Harwood, C. R., Sykes, D. A., Hoare, B., Heydenreich, F. M., Uddin, R., Poyner, D. R., Briddon, S. J., Veprintsev, D. B.. 2020-06-29. Functional solubilisation of the β2-adrenoceptor (β2AR) using Diisobutylene maleic acid (DIBMA).. https://doi.org/10.1101/2020.06.29.171512

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