|signaling pathway figure||1.66||0.7||7807||5|
• Step 1 = hormone/ligand binding to receptor to in itiate/trigger/induce signaling OR signal reception • Step 2 = an intracellular cascade that transduc es/amplifies/transfers the signal from plasma membrane to nucleus (or other cellular effector s) • Step 3 = transcription/expression of target genes is stimulated/repressedHow do multiple steps in a pathway amplify a signal?
Firstly, multiple steps may greatly amplify a signal. If some of the molecules in a pathway transmit the signal to numerous molecules at the next step in the series, the result can be a large number of activated molecules at the end of the pathway.What is a simplified model of the epinephrine signaling pathway?
A simplified model of the epinephrine signaling pathway is represented in Figure 1. Cyclic AMP phosphodiesterase is an enzyme that catalyzes the conversion of cyclic AMP to a different molecule.What are the second messengers in a signal pathway?
Many pathways involve second messengers, small, non-protein molecules that pass along a signal initiated by the binding of a ligand (the “first messenger”) to its receptor. Second messengers include ions; cyclic AMP (cAMP), a derivative of ATP; and inositol phosphates, which are made from phospholipids.