Conformational sensors and domain-swapping reveal structural and functional differences between β-arrestin isoforms

Ghosh, E.; Dwivedi, H.; Baidya, M.; Srivastava, A.; Kumari, P.; Stepniewski, T.; Kim, H. R.; Lee, M.-H.; Gastel, J. v.; Chaturvedi, M.; Roy, D.; Pandey, S.; Maharana, J.; Guixa-Gonzalez, R.; Luttrell, L. M.; Chung, K. Y.; Dutta, S.; Selent, J.; Shukla, A. K.

doi:10.1101/725622

bioRxiv · 10.1101/725622

Conformational sensors and domain-swapping reveal structural and functional differences between β-arrestin isoforms

Ghosh, E.·Dwivedi, H.·Baidya, M.·Srivastava, A.·Kumari, P.·Stepniewski, T.·Kim, H. R.·Lee, M.-H.·Gastel, J. v.·Chaturvedi, M.·Roy, D.·Pandey, S.·Maharana, J.·Guixa-Gonzalez, R.·Luttrell, L. M.·Chung, K. Y.·Dutta, S.·Selent, J.·Shukla, A. K.

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Abstract

Desensitization, signaling and trafficking of G protein-coupled receptors (GPCRs) are critically regulated by multifunctional adaptor proteins, {beta}-arrestins ({beta}arrs). The two isoforms of {beta}arrs ({beta}arr1 and 2) share a high degree of sequence and structural similarity, still however, they often mediate distinct functional outcomes in the context of GPCR signaling and regulation. A mechanistic basis for such a functional divergence of {beta}arr isoforms is still lacking. Using a set of complementary approaches including antibody fragment based conformational sensors, we discover structural differences between {beta}arr1 and 2 upon their interaction with activated and phosphorylated receptors. Interestingly, domain swapped chimeras of {beta}arrs display robust complementation in functional assays thereby, linking the structural differences between the receptor-bound {beta}arr1 and 2 with their divergent functional outcomes. Our findings reveal important insights into the ability of {beta}arr isoforms to drive distinct functional outcomes, and underscore the importance of integrating this aspect in the current framework of biased agonism.

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Ghosh, E., Dwivedi, H., Baidya, M., Srivastava, A., Kumari, P., Stepniewski, T., Kim, H. R., Lee, M.-H., Gastel, J. v., Chaturvedi, M., Roy, D., Pandey, S., Maharana, J., Guixa-Gonzalez, R., Luttrell, L. M., Chung, K. Y., Dutta, S., Selent, J., Shukla, A. K.. 2019-08-05. Conformational sensors and domain-swapping reveal structural and functional differences between β-arrestin isoforms. https://doi.org/10.1101/725622

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