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bioRxiv · 10.1101/2020.07.01.181487

Interactomic affinity profiling by holdup assay: acetylation and distal residues impact the PDZome-binding specificity of PTEN phosphatase

Jane, P.·Gogl, G.·Kostmann, C.·Bich, G.·Girault, V.·Caillet-Saguy, C.·Eberling, P.·Vincentelli, R.·Wolff, N.·Trave, G.·Nomine, Y.
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Abstract

Protein domains often recognize short linear protein motifs composed of a core conserved consensus sequence surrounded by less critical, modulatory positions. Here we used an accurate experimental approach combining high-throughput holdup chromatographic assay and fluorescence polarization to measure quantitative binding affinity profiles of the PDZ domain-binding motif (PBM) of PTEN phosphatase towards the 266 known human PDZ domains. Inclusion of N-terminal flanking residues, acetylation or mutation of a lysine at a modulatory position significantly altered the PDZome-binding profile of the PTEN PBM. A specificity index is also introduced to quantify the specificity of a given PBM over the complete PDZome. Our results highlight the impact of modulatory residues and post-translational modifications on PBM interactomes and their specificity.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Jane, P., Gogl, G., Kostmann, C., Bich, G., Girault, V., Caillet-Saguy, C., Eberling, P., Vincentelli, R., Wolff, N., Trave, G., Nomine, Y.. 2020-07-02. Interactomic affinity profiling by holdup assay: acetylation and distal residues impact the PDZome-binding specificity of PTEN phosphatase. https://doi.org/10.1101/2020.07.01.181487

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