 Many proteins are involved in the process of cell signaling and signal transduction . Some proteins , such as insulin , are extracellular proteins that transmit a signal from the cell in which they were synthesized to other cells in distant tissues . Others are membrane proteins that act as receptors whose main function is to bind a signaling molecule and induce a biochemical response in the cell . Many receptors have a binding site exposed on the cell surface and an effector domain within the cell , which may have enzymatic activity or may undergo a conformational change detected by other proteins within the cell . 
 Many proteins are involved in the process of cell signaling and signal transduction . Some proteins , such as insulin , <a href='drop_aux' title='1'><mark>are</mark></a>extracellular proteins <a href='null_relcl' title='2'><mark>that</mark></a>transmit a signal from the cell in which they <a href='uninflect' title='3'><mark>were</mark></a> synthesized to other cells in distant tissues . Others <a href='drop_aux' title='4'><mark>are</mark></a>membrane proteins <a href='null_relcl' title='5'><mark>that</mark></a>act as receptors whose main function is to bind a signaling molecule and induce a biochemical response in the cell . Many receptors <a href='got' title='6'><mark>have</mark></a> a binding site exposed on the cell surface and an effector domain within the cell , which may have enzymatic activity or may undergo a conformational change detected by other proteins within the cell . 
Many proteins are involved in da process of cell signaling and signal transduction . Some proteins , such as insulin , extracellular proteins transmit a signal from the cell in which they was synthesized to other cells in distant tissues . Others membrane proteins act as receptors whose main function is to bind a signaling molecule and induce a biochemical response in the cell . Many receptors got a binding site exposed on tdacell surface and an effector domain within thdaell , which may have enzymatic activity or may undergo a conformational change detected by other proteins within the cell .