Comprehensive substrate specificity profiling of the human nek kinome reveals unexpected signaling outputs

van de Kooij, B.; Creixell, P.; van Vlimmeren, A.; Joughin, B.; Miller, C. J.; Haider, N.; Linding, R.; Stambolic, V.; Turk, B. E.; Yaffe, M. B.

doi:10.1101/515221

bioRxiv · 10.1101/515221

Comprehensive substrate specificity profiling of the human nek kinome reveals unexpected signaling outputs

van de Kooij, B.·Creixell, P.·van Vlimmeren, A.·Joughin, B.·Miller, C. J.·Haider, N.·Linding, R.·Stambolic, V.·Turk, B. E.·Yaffe, M. B.

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Abstract

Human NimA-related kinases (Neks) have multiple mitotic and non-mitotic functions, but few substrates are known. We systematically determined the phosphorylation-site motifs for the entire Nek kinase family, except for Nek11. While all Nek kinases strongly select for hydrophobic residues in the -3 position, the family separates into four distinct groups based on specificity for a serine versus threonine phospho-acceptor, and preference for basic or acidic residues in other positions. Unlike Nek1-Nek9, Nek10 is a dual-specificity kinase that efficiently phosphorylates itself and peptide substrates on serine and tyrosine, and its activity is enhanced by tyrosine auto-phosphorylation. Nek10 dual-specificity depends on residues in the HRD+2 and APE-4 positions that are uncommon in either serine/threonine or tyrosine kinases. Finally, we show that the phosphorylation-site motifs for the mitotic kinases Nek6, Nek7 and Nek9 are essentially identical to that of their upstream activator Plk1, suggesting that Nek6/7/9 function as phospho-motif amplifiers of Plk1 signaling.

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van de Kooij, B., Creixell, P., van Vlimmeren, A., Joughin, B., Miller, C. J., Haider, N., Linding, R., Stambolic, V., Turk, B. E., Yaffe, M. B.. 2019-01-08. Comprehensive substrate specificity profiling of the human nek kinome reveals unexpected signaling outputs. https://doi.org/10.1101/515221

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