Absence of both Sos-1 and Sos-2 in peripheral CD4(+) T cells leads to PI3K pathway activation and defects in migration.
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ABSTRACT:
SUBMITTER: Guittard G
PROVIDER: S-EPMC4536155 | biostudies-literature | 2015 Aug
REPOSITORIES: biostudies-literature
Publications
Absence of both Sos-1 and Sos-2 in peripheral CD4(+) T cells leads to PI3K pathway activation and defects in migration.
Guittard Geoffrey G Kortum Robert L RL Balagopalan Lakshmi L Çuburu Nicolas N Nguyen Phan P Sommers Connie L CL Samelson Lawrence E LE
European journal of immunology 20150605 8
Sos-1 and Sos-2 are ubiquitously expressed Ras-guanine exchange factors involved in Erk-MAP kinase pathway activation. Using mice lacking genes encoding Sos-1 and Sos-2, we evaluated the role of these proteins in peripheral T-cell signaling and function. Our results confirmed that TCR-mediated Erk activation in peripheral CD4(+) T cells does not depend on Sos-1 and Sos-2, although IL-2-mediated Erk activation does. Unexpectedly, however, we show an increase in AKT phosphorylation in Sos-1/2dKO C ...[more]
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