Structural Biochemistry: Cell Signals

Cells signals can be mainly described as chemical, prokaryotes have sensors capable of detecting nutrients which helps them find food these signals can either be long distance or short distance some of the short distance could be found in muscle cells and a long distance can be describe as the releasing of an egg in the ovaries. Cells have protein receptors which will bind to protein signaling molecules triggering a respond in the molecules. Different receptors are specific for different molecules and within membrane receptors there are 3 major classes of them: G-protein, ion channel and enzyme linked receptors (Cell Signaling Nature Education) which make an external signal into an internal signal these receptors can be sensitive to the atmosphere that surrounds them. …show more content…
Anderson gives us the example of the messenger being epinephrine mainly affecting liver cells; epinephrine will dock to the G-protein because epinephrine is a ligand and they cannot go through the hydrophobic region of the membrane leading to the conformation shape change in the protein this releases alpha subunits that will be added to the enzyme. Adenylyl cyclase this is an inactivated enzyme but once the alpha subunits attach it is ready to do its job converting ATP molecules to cAMP as our secondary messenger which will target protein kinase ( Kinases transfer high energy phosphate groups from one molecule to another) this is composed of 2 catalytic subunits and 2 regulatory subunits, as long as the regulatory subunits are attached it will remain inactive, once cAMP binds to these regulatory portion the catalytic subunits will be release and capable of picking up energy from ATP and act on enzymes within the cells and will drop off a phosphate to phosphorylase so it can release glucose and will eventually shut down again and the cycle will