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Substrate preference and phosphatidylinositol monophosphate inhibition of the catalytic domain of the Per‐Arnt‐Sim domain kinase PASKIN
Author(s) -
Schläfli Philipp,
Tröger Juliane,
Eckhardt Katrin,
Borter Emanuela,
Spielmann Patrick,
Wenger Roland H.
Publication year - 2011
Publication title -
the febs journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.981
H-Index - 204
eISSN - 1742-4658
pISSN - 1742-464X
DOI - 10.1111/j.1742-4658.2011.08100.x
Subject(s) - autophosphorylation , biochemistry , protein kinase a , cyclin dependent kinase 9 , biology , cyclin dependent kinase 2 , map2k7 , ribosomal protein s6 , mitogen activated protein kinase kinase , kinase , microbiology and biotechnology , protein phosphorylation
The Per‐Arnt‐Sim (PAS) domain serine/threonine kinase PASKIN, or PAS kinase, links energy flux and protein synthesis in yeast, regulates glycogen synthesis and protein translation in mammals, and might be involved in insulin regulation in the pancreas. According to the current model, binding of a putative ligand to the PAS domain disinhibits the kinase domain, leading to PASKIN autophosphorylation and increased kinase activity. To date, only synthetic but no endogenous PASKIN ligands have been reported. In the present study, we identified a number of novel PASKIN kinase targets, including ribosomal protein S6. Together with our previous identification of eukaryotic elongation factor 1A1, this suggests a role for PASKIN in the regulation of mammalian protein translation. When searching for endogenous PASKIN ligands, we found that various phospholipids can bind PASKIN and stimulate its autophosphorylation. Interestingly, the strongest binding and autophosphorylation was achieved with monophosphorylated phosphatidylinositols. However, stimulated PASKIN autophosphorylation did not correlate with ribosomal protein S6 and eukaryotic elongation factor 1A1 target phosphorylation. Although autophosphorylation was enhanced by monophosphorylated phosphatidylinositols, di‐ and tri‐phosphorylated phosphatidylinositols inhibited autophosphorylation. By contrast, target phosphorylation was always inhibited, with the highest efficiency for di‐ and tri‐phosphorylated phosphatidylinositols. Because phosphatidylinositol monophosphates were found to interact with the kinase rather than with the PAS domain, these data suggest a multiligand regulation of PASKIN activity, including a still unknown PAS domain binding/activating ligand and kinase domain binding modulatory phosphatidylinositol phosphates. Structured digital abstract• A list of the large number of protein‐protein interactions described in this article is available via the MINT article ID MINT‐8145255