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bioRxiv · 10.1101/2021.01.13.426511

An integrative approach unveils a distal encounter site for rPTPε and phospho-Src complex formation

EswarKumar, N.·Yang, C.-H.·Tewary, S.·Yeh, Y.-Q.·Yang, H.-C.·Ho, M.-C.
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Abstract

Protein tyrosine phosphatase: phospho-protein complex structure determination, which requires to understand how specificity is achieved at the protein level remains a significant challenge for protein crystallography and cryoEM due to the transient nature of binding interactions. Using rPTP{varepsilon}D1 and phospho-SrcKD as a model system, we established an integrative workflow involving protein crystallography, SAXS and pTyr-tailored MD simulations to reveal the complex formed between rPTP{varepsilon}D1 and phospho-SrcKD, revealing transient protein-protein interactions distal to the active site. To support our finding, we determined the associate rate between rPTP{varepsilon}D1 and phospho-SrcKD and showed that a single mutation on rPTP{varepsilon}D1 disrupts this transient interaction, resulting in the reduction of association rate and activity. Our simulations suggest that rPTP{varepsilon}D1 employs a binding mechanism involving conformational change prior to the engagement of cSrcKD. This integrative approach is applicable to other PTP: phospho-protein complex determination and is a general approach for elucidating transient protein surface interactions.

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EswarKumar, N., Yang, C.-H., Tewary, S., Yeh, Y.-Q., Yang, H.-C., Ho, M.-C.. 2021-01-14. An integrative approach unveils a distal encounter site for rPTPε and phospho-Src complex formation. https://doi.org/10.1101/2021.01.13.426511

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