Signal Transduction Pathways

Created March 2020, Offline version here
Video by Paul Anderson, also on his website Bozeman Science.

    Signal transduction pathways work by either modifying a (changing its ) or a(n) cascade, where a high energy will be passed on from one chemical to another. In our example, epinephrine, produced by the adrenal glands, is the that binds to the receptor that has many subunits. When the receptor structure changes, the subunit dissociates from the receptor and binds to to activate the membrane protein and generate lots of to amplify the message.
As a messenger, cAMP binds to the two subunits of which causes these subunits to dissociate from the two subunits of the protein that speed up chemical reactions. These activated subunits are then . The activated subunit then passes a group to , activating the enzyme so it can break down into as an energy source for the cell. Once the is no longer bound to the receptor, we no longer make and the whole pathway is .