RTK Flashcards
Insulin receptor
Receptor tyrosine kinase
= plasma membrane receptor
Active when phosphorylated
RTK structure
Alpha subunit = 2x = extracellular
Beta subunit = 2x = transmembrane, cytosol
1 ligand binds to monomer in dimerized RTK
RTK function
Protein that phosphorylates tyr residues on target proteins
When insulin binds, activation loop moves and binding sits become available for Ps
For insulin : phosphorylated partner beta unit
Each unit needs 3 p groups = 6 total per receptor
How many atp needed per RTK activation with insulin?
6
SH2 Domains
Bind to phosphotyrosine residues
SH3 Domains
Bind to proline rich
= pro or p
What domains allow Grb2 to act as a Lego?
SH2 and SH3
Ras Details
Rat sarcoma
Important for regulating cell division
Mutations = cancer
Needs GTP bound for activity
PI3K
Phosphoinositide 3 kinase
Binds to IRS1 via sh2 domain
PIP3 details
Negatively charged head is inside cell
Binds to protein kinase b
What small G proteins does PKB act in to stimulate GLUT4 transport?
RAC1, rab
Racing rabbits = squirmy = butt squirm on park bench via your glutes
Mitogenic vs metabolic cascades
Mitogenic = mighty MAPK cascade
Metabolic = PI3K Cascade
MAPK cascade memory
IRS1 is everywhere
Lego man (Grb2) grabs IRS attention for SOS of the people
The sons of the seven daughters are engaging with the cancerous rats (Ras) which are so big that they are tripling rather than doubling in size (GDP to GTP)
They are the rid raf of society (Raf1)
They work together to give 2 pies to the ser mechanics (MEK) to sabotage the transportation of the Evil Rich Karls (ERK) (tires = thr and tyr)
Bc transportation is sabotaged they end up in a strange place in nucleus where Elks roam the surf
(ELK1) is phosphorylated and can interact with SRF = activates transcription for cell division
Also insulin modulating genes
Kinases in MAPK cascade
RTK
Raf1 = mapkkk
MEK = MAPkk
Not or but and
ERK = MAPK
PI3K pathway memory
IRS is everywhere
One guy is spying on his crush, pip, Who loves pie
Wants a pie for a kiss = PI3K
Going to take effort/ energy = hike = atp
Pip had two pies but now has 3 = PIP3
They sit on park bench = PKB
Leads to public display of kissing = PDK1 = not very gentlemenly = sers in question = pie as excuse
Buttttt Great Saliva Kiss is inhibited by Pie = can’t kiss with mouth full
=glycogen synthase kinase = GSK
But great salvia remains in order to eat
GS remains activated = glycogen synthesis
Park bench also activates booty wiggling = GLUT4 activation
