Links
Objectives
- Be able to describe the types of cell signaling
- Be able to predict the receptor type based on the ligand
- Be able to discuss the results of cell signaling
Key points
- Signaling involves the interaction of a ligand with a receptor
- ligands are molecules that induce a sensory cell to respond
- receptors are specific to a particular ligand and initiate signal transduction
- Signal types are classified based on signaling distance
- autocrine signals target receptors in same cell
- paracrine signaling targets cells near the originating cell
- endocrine signals travel through the circulatory system
- some signals travel between adjacent cells via gap junctions, synapses
- location of receptors depends on properties of ligand
- transmembrane receptors bind to ligand outside cell
- ion channel-linked, protein kinase, G protein-coupled receptors
- cytoplasmic / nuclear receptors bind to ligand inside cell
- steroid hormone receptors
- transmembrane receptors bind to ligand outside cell
- reception → transduction → response
- example responses: enzyme activation, gene expression, physiological change
In-class activities
- Read the paper bundle Innovation in Cannabis Medicineand respond to the following questions:
- What is the biologiacl basis for the researchers to believe that THC effects on the brain could be separate from its effects on pain?
- What kind of receptor is the glycine receptor? What kind is the CB1R?
- Why did the researchers modify the glycine receptor, and what did they conclude?
- Why did the researchers modify the THC molecule, and what did they conclude from these experiments?