Molecular basis of Tousled-Like Kinase 2 activation
Tousled-like kinases (TLKs) are required for genome stability and normal development in numerous organisms and have been implicated in breast cancer and intellectual disability. In humans, the similar TLK1 and TLK2 interact with each other and TLK activity enhances ASF1 histone binding and is inhibited by the DNA damage response, although the molecular mechanisms of TLK regulation remain unclear. Here we describe the crystal structure of the TLK2 kinase domain. We show that the coiled-coil domains mediate dimerization and are essential for activation through ordered autophosphorylation that promotes higher order oligomers that locally increase TLK2 activity. We show that TLK2 mutations involved in intellectual disability impair kinase activity, and the docking of several small-molecule inhibitors of TLK activity suggest that the crystal structure will be useful for guiding the rationale design of new inhibition strategies. Together our results provide insights into the structure and molecular regulation of the TLKs. ; Novo Nordisk Foundation Center for Protein Research is supported fi nancially by the Novo Nordisk Foundation (Grant NNF14CC0001) and the Danish Cancer Foundation for a grant to G.M. T.H.S. is supported by the Ministerio de Economía y Competitividad (MINECO) (BFU2015-68354, Ayudas para incentivar la incorporación estable de doc- tores (IED) 2015 and institutional funding through the Centres of Excellence Severo Ochoa award and from the CERCA Programme of the Catalan Government), S.S.B. by a predoctoral fellowship from Fundacio La Caixa and M.V.P. by a Severo Ochoa FPI predoctoral fellowship (MINECO). P.R. is supported by the Marie Sk ł odowska-Curie European Training Network (ETN) " TEMPERA. We would like to thank the Protein Production Facility Platform at CPR for the excellent technical assistance, M. Orozco at IRB Barcelona for helping with the initial modelling analysis and also thank the PRO-MS Danish National Mass Spectrometry Platform for Functional Proteomics and the CPR Mass Spectrometry Platform for instrument support and assistance.