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bioRxiv · 10.1101/2021.03.22.436451

A proteome-wide screen uncovers diverse roles for sequence context surrounding proline-rich motifs in Ena/VASP molecular recognition

Hwang, T.·Parker, S. S.·Hill, S. M.·Ilunga, M. W.·Grant, R. A.·Sivaraman, V.·Mouneimne, G.·Keating, A. E.
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Abstract

The human proteome is replete with short linear motifs (SLiMs) of 4-6 residues that are critical for protein-protein interactions, yet the importance of the sequence surrounding such motifs is underexplored. We devised a proteomic screen to systematically examine the influence of SLiM sequence context on protein-protein interactions. Focusing on the EVH1 domain of ENAH, an actin regulator that is upregulated in invasive cancers, we screened 36-residue proteome-derived peptides for binding. We discovered a pocket on the ENAH EVH1 domain that diverged from its orthologs to recognize extended SLiMs, and we found that proteins with two EVH1-binding SLiMs can wrap around a single domain. We also found that the ciliary protein PCARE uses an extended 23-residue region to obtain higher affinity than any known ENAH EVH1-binding motif. Our screen provides a way to uncover the effects of broader proteomic context on motif-mediated interactions, revealing diverse mechanisms of contextual control over EVH1 interactions and establishing that SLiMs cant be fully understood outside of their native context.

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Hwang, T., Parker, S. S., Hill, S. M., Ilunga, M. W., Grant, R. A., Sivaraman, V., Mouneimne, G., Keating, A. E.. 2021-03-22. A proteome-wide screen uncovers diverse roles for sequence context surrounding proline-rich motifs in Ena/VASP molecular recognition. https://doi.org/10.1101/2021.03.22.436451

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