Cell Regulation Flashcards
What are the types of membrane receptors?
- GPCR
- Tyrosine Kinase
- JAK Kinase
- Ser/Thr Kinase
- Guanylate cyclase
- Ion Gated
What is characteristic of Diabetes Insipidus?
- Deficiency in ADH action
- Neurogenic: No functional ADH
- Nephrogenic: No functional ADH response due to mutation in V2-R or AQ2
What type of receptor is the V2 receptor (ADH)?
GPCR
What are the components of the GPCR?
- alpha
- beta
- gamma
What action happens after stimulation of the alpha subunit by an external stimuli?
- alpha(s) subunit stimulates adenyl cyclase to increase cAMP
Or
- alpha (i) inhibits adenylyl cyclase and therefore decreases cAMP
How does the pertussis toxin affect intracellular signaling pathways?
B. pertussis secretes pertussis toxin,
which ADP ribosylates the αi subunit which inactivates αi, and reduces the inhibition of
adenylyl cyclase
What affect does activation of alpha (q) subunit have?
- Activates PLC, which cleaves PIP2 to become IP3 and DAG
Which factor is stimulated by the V2 receptor pathway to enter the nucleus and stimulate gene activation resulting in an increase in AQ2 insertion?
CREBP
What second messenger system is activated by the V2 vasopressin receptor?
1. G alpha-s stimulation of adenylate cyclase 2. G alpha-i inhibition of adenylate cyclase 3. Tyrosine kinase 4. Guanylate cyclase 5. Gq stimulation of phospholipase C
- G alpha-s stimulation of adenylate
cyclase
What type of receptor is the insulin receptor?
- G protein associated receptor
- Tyrosine kinase
- Receptor associated with a JAK tyrosine kinase
- Guanylate cyclase
- Ion channel
- Tyrosine kinase
What mutation occurs to CFTR in CF patients?
508del of Phe
- Transporter does not reach plasma membrane due to defect leading to symptoms
What is the pathway of Insulin from DNA to exocytosis?
Regulated Insulin Secretion Pathway
DNA → transcription → hnRNA processing and exon splicing → mRNA → ribosome → docking to the RER → Protein synthesis and processing at RER → Transport to Golgi → Processing, sorting and packaging into
vesicles by Golgi → Vesicles transported
along microtubules (kinesins & dyneins) → Cytoplasmic Ca++ increases → Exocytosis
What are the two calcium-activated receptors?
- IP3R
- Ryanodine
What are common 2nd messengers of GCPRs?
- cAMP
- cGMP
- IP3
- DG/DAG
- Ca++
Describe the affect of Epinephrine on secondary messengers.
EP binds GCPR alpha-2 receptors, which contain a alpha-i subunit which bind adenylyl cyclase and inhibit cAMP.