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bioRxiv · 10.1101/250753

Fine-tuning of substrate preferences of the Src-family kinase Lck revealed through a high-throughput specificity screen

Shah, N. H.·Löbel, M.·Weiss, A.·Kuriyan, J.
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Abstract

To obtain a comprehensive map of the intrinsic specificities of tyrosine kinase domains, we developed a high-throughput method that uses bacterial surface-display and next-generation sequencing to analyze the specificity of any tyrosine kinase against a library of thousands of peptides derived from human tyrosine phosphorylation sites. Using this approach, we identified a difference in the electrostatic recognition of substrates between the cytoplasmic Src-family tyrosine kinases Lck and c-Src. This divergence likely reflects the specialization of Lck to act in concert with the tyrosine kinase ZAP-70 in T cell receptor signaling. The current understanding of substrate recognition by tyrosine kinases emphasizes the role of localization by non-catalytic domains, but our results point to the importance of direct recognition at the kinase active site in fine-tuning specificity. Our method provides a simple approach that leverages next-generation sequencing to readily map the specificity of any tyrosine kinase at the proteome level.

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Shah, N. H., Löbel, M., Weiss, A., Kuriyan, J.. 2018-01-19. Fine-tuning of substrate preferences of the Src-family kinase Lck revealed through a high-throughput specificity screen. https://doi.org/10.1101/250753

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