BIOLOGY 151 Lecture Notes - Lecture 27: Endothelium, Cell Signaling, Autocrine Signalling
Document Summary
To have communication between cells you must have a receptor, signaling molecule, and a responding cell. Hormone binds to receptor and changes the protein"s shape and function. 3 cells a, b, c could tell cell to divide. Add molecules d, e tell cell to grow. Swap molecule e for g and it causes cell to differentiate. Absence of any signalling results in death. Type of cell being signaled to changes the role/function. As well as cell-surface receptors, there are also intracellular receptors. Small, nonpolar signaling molecule can pass through the cell membrane. Nerve signals to endothelial cells to make no, then no leaves those cells and enters smooth muscle cells which results in muscle relaxation. You strip off any proteins on the cell surface by using a protease. Now when you add a specific signaling molecule, the cell still responds. Because the receptor is on the interior of the cell. There is a receptor that gets activated by a ligand.
