Unit 3 - Cancerous Cells + Adrenaline Pathway Flashcards
How are cancer cells created?
Through uncontrollable and rapid cell division.
- creates error allowing for cells to have mixed chromosomal levels, and cells will not have the correct number of chromosomes –> mutations
What is the function of the EGF and MAPK Pathway?
Stimulates Cell Division
- Triggers cell replication
- Triggers growth of the cell
- Shuts down mutated cells and forces it into cell death, decreasing cancer cells
What does the Receptor Tyrosine Kinase (RTK) do?
EGF Receptor that activates the Ras and MAP Kinase pathway
What does GEF do?
- Activates RAS
- Replaces GDP with GTP
What does GAP do?
- Deactivates RAS
- turns RAS GTPase (self regulating aspect)
How does RAS Self Regulate and turns itself off?
Through using GTPase
–> an enzyme which removes a Phosphate group and changes the GTP to GDP and it is no longer active
What is the Her 2?
- A membrane tyrosine kinase and has potential to
cause cancer - A certain Receptor Protein
- “Her 2 Receptors”
What happens if a person is Her 2+
- Causes more aggressive cancer
- Easier to treat because there is a way to pinpoint
the issue
Activates cell division when not signaled too
–> cause rapid and uncontrollable cell division
What does it mean if the patient is Her 2-?
- Cancer not as aggressive
- Harder to treat since there is not a direct issue
- Do not have an abnormal amount of Her 2 proteins
- Her 2 proteins are not the issue that cause cancer
- cancer is caused by other issues
What happens if patients are given drugs that target different parts of the mutated pathway?
Does NOT remove the cancer
But it helps increase life span
Where are the checkpoints in mitosis?
G1 G2 and G0
What is the order of the RAS and MAPK pathway?
RAS –> RAF –> MEK –> MAPK / ERK
What does EGF (Epidermal Growth Factor) signals cause?
They activate cell division pathways
Explain the EGF and MAPK pathway
- A EGF Factor comes in
- The EGF Receptor (Tyronise Kinase Receptor) is activated
- Receptor activates GEF
- GEF turns Ras On
- Ras touches RAF and activates it
- GAP activates GTPase turning RAS off
- RAF Phosphorylates MEK
- MEK phosphorylates ERK
- ERK activates transcription factors
What does the Adrenaline Pathway do?
Activated by Epinepherine which causes a fight or flight response
What are G coupled receptors
Receptor types which have a Gprotein complex attached to the receptor, that when the receptor is activated it will let go of the G protein and it can activate its cascade
In the adrenaline pathway how does the receptor activate the g protein alpha to activate the effector
through exchanging GDP to GTP
What happens to the g protein once activated
it lets go of the gamma and beta parts of the g protein and activates the effector = Adenylyl Cyclase
What does the Adenylyl Cyclase effector do?
- once g protein alpha activates the Adenylyl Cyclase
- takes in ATP from donating mitochondria
- Converts to cAMP = removes 2 Phosphate groups
- cAMP binds to the regulatory subunit –> once binded it can release the Protein Kinase “A”
- PKA then activates targeted proteins
What is a second messenger protein
It is an activated proteins which relay a message sent by extracellular signals
