Cell Signaling ILM Flashcards
Target receptors are on the same cell. Signaling to itself (releases the extracellular signal and also has receptors for that signal)
autocrine signaling
Ligand on signaling cell binds to target cell receptors (not floating in space, displaying to the cell next door)
juxtacrine signaling
o Cytokines by T helper cells upregulate T helper cell activity
what type of signaling is this?
autocrine signaling
o Interactions between T lymphocytes and APCs
what type of signaling is this?
juxtacrine signaling
Target sites are on adjacent cells, the extracellular signaling molecule floats around and then finds the receptor. Rapid breakdown of the ligand helps prevent distant effects.
paracrine signaling
o Cytokines secreted by T helper cells upregulate activity of macrophages
what type of signaling is this?
paracrine signaling
Target sites are on distant cells (ex: hormones through blood stream). what kind of signaling is this?
endocrine signaling
Cytoplasmic domain (when activated by ligand-binding on extracellular side of receptor) bind a GTP binding protein (G protein). The G protein dissociates into active components that activate an effector molecule (ex – AC). This recruits second messengers (such as cAMP). What receptor type is this?
G-protein coupled receptor
when bound by the appropriate ligand, change conformation in such a way that a channel opens up across the membrane and allows ions to enter or leave the cell.
ligand gated ion channels
phosphorylated by a cytoplasmic kinase that interacts with the ligand-bound receptor OR self-activates by becoming phosphorylated when the receptor is bound by ligand. Phosphorylation of this receptor initiates cascade of kinase-mediated phosphorylation events that regulate gene expression.
kinase-linked receptors
Lipid-soluble signaling molecules can diffuse across the plasma membrane into the cell. They bind to receptors in the cytoplasm (commonly in nucleus). The ligand-bound receptor then functions to alter gene expression and protein synthesis.
intracellular receptors
remove phosphate groups
phosphotases
