The series of molecular signals initiated by activation of a receptor on the surface of a cell. The pathway begins with binding of an extracellular ligand to a cell surface receptor, or for receptors that signal in the absence of a ligand, by ligand-withdrawal or the activity of a constitutively active receptor. The pathway ends with regulation of a downstream cellular process, e.g. transcription.
chloroplast-nucleus signaling pathway
dopamine receptor signaling pathway +
endoplasmic reticulum unfolded protein response +
ER-nucleus signaling pathway +
extracellular ATP signaling
G protein-coupled receptor signaling pathway +
granzyme-mediated programmed cell death signaling pathway +