Trysine Kinsase Receptors Flashcards
1
Q
Where is insulin produced?
A
Beta cells of the pancreas
2
Q
How is insulin released?
A
- glucose transported in by GLUT2 transporters
- increases energy production
- ATP closes KATP channels - depolarisation
- opens voltage gates Ca2+ channels
- Ca2+ influx - binds to synaptogamin
3
Q
How is insulin released via G proteins?
A
- glucagon stimulates a Gs G protein
- cAMP production
- activates PKA
- changes conformation of snare proteins
4
Q
What are the types of catalytic receptors?
A
- receptor tyrosine kinase
- tyrosine kinase associated receptors
- receptor serine/threonine kinases
- receptor tyrosine phosphatase
- receptor granylate cyclise
5
Q
What does IRS stand for?
A
Insulin response substrates
6
Q
What are IRS?
A
A collection of proteins
7
Q
What does PI-3P stand for?
A
Phosphatidyl linositol-3-phosphate
8
Q
How does insulin increase the intake and use of glucose?
A
- insulin receptors autophosphorylate
- IRS are phosphorylated
- phosphatidylinositol is phosphorykated to PI-3P
- activates protein kinase B
- PKA activates glycogen synthase and adds GLUT4 transporters to the membrane
9
Q
What does MAPK stand for?
A
Mitogen activates protein kinase
10
Q
How does insulin change gene expression?
A
- insulin binding causes receptors to autophosphorylate
- through many intermediate steps MAPK gets activated
- MAPK translocates to the cell nucleus
- MAPK phorphorylates transcription factors to change gene expression
