L4_ Receptors and signaling: B cell receptor and T cell receptor Flashcards
What is the first step to initiate intracellular signaling that leads to the activation of PLC?
Tyrosine phosphorylation
PIP2 is converted to what molecules by PLC?
- IP3
- DAG
What are the downstream events of IP3?
IP3/ Ca2+/ NFAT
What are the downstream events of DAG?
- DAG/Ras/ MAPK/ AP-1
- DAG/PKC/IKK/NFkB
What is the costimulatory signaling pathway?
PIP2/PIP3/PI3K/Akt
The costimulatory signaling is an antiapoptotic or pro-apoptotic pathway?
Antiapoptotic
What is anergy?
Unresponsiveness of the T cell
The lack of costimulatory signaling leads to what events?
- Anergy
- Apoptosis
- Immune tolerance
What receptor proteins carry ITAMs for TCR signaling and BCR signaling?
Hexametric CD3 for TCR
Ig-alpha/beta (CD79 alpha/beta) in BCR
What are the kinases that phosphorylate the tyrosine in ITAM in TCR and BCR signaling?
BCR (Ig alpha/ beta) - Lyn
TCR (CD3) - Lck
What enzyme is recruited to the membrane by phosphorylated tyrosine to break down PIP2?
Phospholipase (PLC)
What transcription factor does IP3 signaling activates?
NFAT
Which two proteins do DAG activates?
Ras and PKC
Which two transcription factors are activated through the DAG signaling?
Ap-1 and NF-kappa-B
The Ras pathway involves a cascade of phosphorylation of which two kinds of amino acids?
Serine and threonine
AP-1 activates the transcription of which gene?
IL-2
Which two processes activates IKK?
Phosphorylation and ubiquitination
