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TCR and IL-7 Signaling Are Altered in the Absence of Functional GTPase of the Immune Associated Nucleotide Binding Protein 5 (GIMAP5).

ABSTRACT: GTPase of the immune associated nucleotide binding protein (GIMAP) family of proteins are expressed essentially in cells of the hematopoietic system. Mutation in the founding member of this gene family, Gimap5, results in the lymphopenic phenotype in Bio-Breeding diabetes prone rats. In mice, deletion of functional Gimap5 gene affects the survival and renewal of hematopoietic stem cells in addition to the defects observed in T cells. Here we show that T cells from OTII TCR-transgenic Gimap5sph/sph mice do not proliferate in response to its cognate antigen. Furthermore, T cells from Gimap5 mutant rats and mice show decreased phosphorylation of STAT5 following stimulation with IL-7. Our results suggest that functional Gimap5 is required for optimal signaling through TCR and IL-7R in T cells.

SUBMITTER: Chen XL

PROVIDER: S-EPMC4811415 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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TCR and IL-7 Signaling Are Altered in the Absence of Functional GTPase of the Immune Associated Nucleotide Binding Protein 5 (GIMAP5).

Chen Xi-Lin XL Serrano Daniel D Ghobadi Farnaz F Mayhue Marian M Hoebe Kasper K Ilangumaran Subburaj S Ramanathan Sheela S

PloS one 20160329 3

GTPase of the immune associated nucleotide binding protein (GIMAP) family of proteins are expressed essentially in cells of the hematopoietic system. Mutation in the founding member of this gene family, Gimap5, results in the lymphopenic phenotype in Bio-Breeding diabetes prone rats. In mice, deletion of functional Gimap5 gene affects the survival and renewal of hematopoietic stem cells in addition to the defects observed in T cells. Here we show that T cells from OTII TCR-transgenic Gimap5sph/s ...[more]

PMID: 27023180

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