Leukocyte migration: dismantling inhibition.
A new study demonstrates that the Src-family kinases Fgr and Hck inhibit chemokine signaling in polymorphonuclear leukocytes and dendritic cells by phosphorylation of PIR-B, an inhibitory receptor expressed on leukocytes. In resting cells, PIR-B phosphorylation is constitutive but is decreased transiently by addition of chemokines. In Fgr/Hck-deficient cells, constitutive PIR-B phosphorylation is markedly decreased. These Src-family kinases have a novel role in tonic inhibition of cell activation that must be overcome to allow the phenotypic effects of chemokine signaling through G-protein-coupled receptor ligands.
Program in Microbial Pathogenesis and Host Defense, University of California-San Francisco, Campus Box 2140, 600 16th Street, San Francisco, CA 94123, USA. ebrown@medicine.ucsf.edu
Eric J
EJ
Brown
D018925:Chemokines / Q000378:metabolism*; D002634:Chemotaxis, Leukocyte / Q000502:physiology*; D007962:Leukocytes / Q000166:cytology* / Q000378:metabolism*; D015398:Signal Transduction
D018925:Chemokines