Curriculum
Module 06 · 55 min
Signal Transduction Basics
GPCRs, second messengers, and the universal grammar of cell signaling.
CoreClinicalResearch
Topics
What this module covers
- 01Receptor classes: GPCR, RTK, ion channel, nuclear
- 02Second messengers: cAMP, IP3/DAG, Ca2+, NO
- 03Amplification and desensitization
- 04How most prescription drugs target signaling
Learning objectives
By the end of this module you will be able to
- L01Classify the four major receptor families and an example drug for each.
- L02Trace a Gs-coupled signal from ligand to PKA-mediated phosphorylation.
- L03Explain receptor desensitization and tachyphylaxis.
Expected takeaways
What you should walk away believing
- →≈30% of FDA-approved drugs act on GPCRs.
- →Signal amplification means femtomolar ligand → millimolar second messenger.
- →Receptor desensitization underlies opioid tolerance and beta-blocker rebound.
Core summary
At the Core level
Cells receive signals through receptors that convert outside-the-cell information into inside-the-cell biochemistry. The same handful of cascades — cAMP, calcium, MAPK — re-appear across nearly every tissue and disease.
Evidence-graded claims
Claims, scored A–F
A
GPCRs are the largest druggable target class
Hauser et al., Nat Rev Drug Discov 2017.
A
All GPCRs are 7-transmembrane
Defining structural feature.
Quiz
Check your understanding
Q1. Which second messenger does Gq-PLC produce?
Flashcards
Lock it in
1 / 2
Front
Gs vs Gi effect on cAMP?
Click to flip