Pathway: Interleukin receptor SHC signaling
Reactions in pathway: Interleukin receptor SHC signaling :
Interleukin receptor SHC signaling
Phosphorylation of Shc at three tyrosine residues, 239, 240 (Gotoh et al. 1996) and 317 (Salcini et al. 1994) involves unidentified tyrosine kinases presumed to be part of the activated receptor complex. These phosphorylated tyrosines subsequently bind SH2 signaling proteins such as Grb2, Gab2 and SHIP that are involved in the regulation of different signaling pathways. Grb2 can associate with the guanosine diphosphate-guanosine triphosphate exchange factor Sos1, leading to Ras activation and regulation of cell proliferation. Downstream signals are mediated via the Raf-MEK-Erk pathway.Grb2 can also associate through Gab2 with PI3K and with SHIP.
Figure reproduced from Gu, H. et al. 2000. Mol. Cell. Biol. 20(19):7109-7120
Copyright American Society for Microbiology. All Rights Reserved.
Figure reproduced from Gu, H. et al. 2000. Mol. Cell. Biol. 20(19):7109-7120
Copyright American Society for Microbiology. All Rights Reserved.
Cytokines are small proteins that regulate and mediate immunity, inflammation, and hematopoiesis. They are secreted in response to immune stimuli, and usually act briefly, locally, at very low concentrations. Cytokines bind to specific membrane receptors, which then signal the cell via second messengers, to regulate cellular activity.
Humans are exposed to millions of potential pathogens daily, through contact, ingestion, and inhalation. Our ability to avoid infection depends on the adaptive immune system and during the first critical hours and days of exposure to a new pathogen, our innate immune system.