Signaling Pathways

Question 1

MAP kinase

Answer 1

GTP bound Ras binds Raf; Raf phos MEK; MEK phos ERK; ERK phos targets and TFs

Question 2

GAP (GTPase activating protein)

Answer 2

takes protein from GTP –> GDP

Question 3

GEF (Guanylyl exchange factor)

Answer 3

takes protein from GDP–>GTP

Question 4

JAK/STAT

Answer 4

JAK is a nonreceptor protein tyrosine kinase; phos its own Tyr residues
JAK associates with cytokine receptors
STAT once phos will dimerize and translocate to the nucleus to act as TFs

Question 5

TGF-beta/ Smad

Answer 5

TGF-beta is the ligand; once it binds protein Ser/Thr kinase receptors, one monomer will phos the other at Ser/Thr residues; this will phos Smad; phos-Smad translocates to nucleus and acts as TFs

Question 6

NF-kB

Answer 6

binds cytokines, PAMPs and GFs; ligand binding will activate inhibitory kB kinase, it will phos, ubiq and degrade iKB and NF-kB will be able to translocate to the nucleus as TF

Question 7

Rho

Answer 7

activated by integrins or GF receptors; will help actin polymerize and phosmyosin

Question 8

PI3 kinase

Answer 8

will take PIP2–>PIP3; this will activate Akt which is a kinase that helps with cell survival and protein synthesis

Question 9

Phospolipase C

Answer 9

will take PIP2 into IP3 and DAG; PLC is activated by the ligand binding of a GPCR and the effect of Gq protein

Question 10

IP3

Answer 10

will diffuse to activate Ca2+ protein sensors or induce Ca2+ out of the ER

Question 11

DAG

Answer 11

will activate protein kinase C which will phos proteins