Small effective molecules mediated signaling ligand Recepto Relay protein or transmitor Plasms membrane ctor Sw Small effective molecules Intracellular signaling proteins Terminal target proteins ( Metabolic enzyme, latent target genes regulatory protein, cytoskeletonal protein Altered metabolism gene expression cell shape or movementEffector ligand Terminal target proteins Relay protein or transmitor Small effective molecules Intracellular signaling proteins Small effective molecules mediated signaling （Metabolic enzyme，latent target genes regulatory protein，cytoskeletonal protein） Altered metabolism gene expression cell shape or movement Plasms membrane Receptor