CELL COMMUNICATIO

NSChapter 5.5-5.6

TYPES OF COMMUNICATION Differentiate between the following:

ParacrineEndocrineAutocrine

STEPS TO COMMUNICATE

STEP 1: MULTIPLE RECEPTOR TYPES Cytoplasmic receptor proteins Membrane bound receptor proteins

G-protein linked receptorsReceptor tyrosine kinasesLigand gated ion channels

Be able to compare and contrast each of the above.

Know what type of signals activate each Provide examples of each

CYTOPLASMIC RECEPTORS

How do they work?

What is different about the chemistry of the signals?

G-PROTEIN LINKED RECEPTORHow does it work?

What is different about the GDP to GTP transition as compared to the GTP to GDP transition?

RECEPTOR TYROSINE KINASES

How does it work?

LIGAND GATED ION CHANNELS

How does it work?

STEP 2: TRANSDUCTION

Second messengers

Phosphorylation cascades

SECOND MESSENGERS

What are they?

Examples?

Advantages to using them?

SECOND MESSENGERS

PHOSPHORYLATION CASCADE

What are they? Advantages?

REGULATING SIGNAL TRANSDUCTION How does a cell regulate this process?

While the number of “steps” creates increased regulation, it also creates increased risk of malfunction. Explain.

STEP 3: RESPONSE

Likely responses to a signal???

SPECIFICITY OF THE SIGNAL

PUTTING IT ALL TOGETHER

EXAMPLES TO BE FAMILIAR WITH

How does caffeine interfere with a signaling pathway to keep us “perky”?

- adenosine receptor antagonist - inhibitor of cAMP phosphodiesterase

Be able to explain the epinephrine pathway from signal to response!