DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies

Localization of DEF6 (SLAT/IBP), a Rho-family guanine nucleotide exchange factor, to the center of the immune synapse is dependent upon ITK, a Tec-family kinase that regulates the spatiotemporal organization of components of T cell signaling pathways and Cdc42-dependent actin polymerization. Here we...

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Main Authors: Hey, Fiona, Czyzewicz, Nathan, Jones, Peter, Sablitzky, Fred
Format: Article
Published: American Society for Biochemistry and Molecular Biology
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Online Access:https://eprints.nottingham.ac.uk/2918/
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author Hey, Fiona
Czyzewicz, Nathan
Jones, Peter
Sablitzky, Fred
author_facet Hey, Fiona
Czyzewicz, Nathan
Jones, Peter
Sablitzky, Fred
author_sort Hey, Fiona
building Nottingham Research Data Repository
collection Online Access
description Localization of DEF6 (SLAT/IBP), a Rho-family guanine nucleotide exchange factor, to the center of the immune synapse is dependent upon ITK, a Tec-family kinase that regulates the spatiotemporal organization of components of T cell signaling pathways and Cdc42-dependent actin polymerization. Here we demonstrate that ITK both interacts with DEF6 and phosphorylates DEF6 at tyrosine residues Tyr210 and Tyr222. Expression of a GFP-tagged Y210E-Y222E phosphomimic resulted in the formation of DEF6 cytoplasmic granules that co-localized with decapping enzyme 1 (DCP1), a marker of P-bodies; sites of mRNA degradation. Similarly treatment of cells with puromycin or sodium arsenite, reagents that arrest translation, also resulted in the accumulation of DEF6 in cytoplasmic granules. Bioinformatics analysis identified a glutamine-rich, heptad-repeat region; a feature of aggregating proteins, within the C-terminal region of DEF6 with the potential to promote granule formation through a phosphorylation-dependent unmasking of this region. These data suggest that in addition to its role as a GEF, DEF6 may also function in regulating mRNA translation.
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spelling nottingham-29182020-05-04T20:34:37Z https://eprints.nottingham.ac.uk/2918/ DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies Hey, Fiona Czyzewicz, Nathan Jones, Peter Sablitzky, Fred Localization of DEF6 (SLAT/IBP), a Rho-family guanine nucleotide exchange factor, to the center of the immune synapse is dependent upon ITK, a Tec-family kinase that regulates the spatiotemporal organization of components of T cell signaling pathways and Cdc42-dependent actin polymerization. Here we demonstrate that ITK both interacts with DEF6 and phosphorylates DEF6 at tyrosine residues Tyr210 and Tyr222. Expression of a GFP-tagged Y210E-Y222E phosphomimic resulted in the formation of DEF6 cytoplasmic granules that co-localized with decapping enzyme 1 (DCP1), a marker of P-bodies; sites of mRNA degradation. Similarly treatment of cells with puromycin or sodium arsenite, reagents that arrest translation, also resulted in the accumulation of DEF6 in cytoplasmic granules. Bioinformatics analysis identified a glutamine-rich, heptad-repeat region; a feature of aggregating proteins, within the C-terminal region of DEF6 with the potential to promote granule formation through a phosphorylation-dependent unmasking of this region. These data suggest that in addition to its role as a GEF, DEF6 may also function in regulating mRNA translation. American Society for Biochemistry and Molecular Biology Article PeerReviewed Hey, Fiona, Czyzewicz, Nathan, Jones, Peter and Sablitzky, Fred DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies. Journal of Biological Chemistry, 287 (37). pp. 31073-31084. ISSN 0021-9258 Cell Biology Guanine Nucleotide Exchange Factor (GEF) P-body Signal Transduction T-cell Receptor http://www.jbc.org/content/287/37/31073.long doi:10.1074/jbc.M112.346767 doi:10.1074/jbc.M112.346767
spellingShingle Cell Biology Guanine Nucleotide Exchange Factor (GEF) P-body Signal Transduction T-cell Receptor
Hey, Fiona
Czyzewicz, Nathan
Jones, Peter
Sablitzky, Fred
DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies
title DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies
title_full DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies
title_fullStr DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies
title_full_unstemmed DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies
title_short DEF6, a novel substrate for the tec kinase ITK, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with P-bodies
title_sort def6, a novel substrate for the tec kinase itk, contains a glutamine-rich aggregation-prone region and forms cytoplasmic granules that co-localize with p-bodies
topic Cell Biology Guanine Nucleotide Exchange Factor (GEF) P-body Signal Transduction T-cell Receptor
url https://eprints.nottingham.ac.uk/2918/
https://eprints.nottingham.ac.uk/2918/
https://eprints.nottingham.ac.uk/2918/