BSI Lecture 17-18 Cell Signaling Examples

Question 1

cAMP most important target is ________ __

Answer 1

Phosphokinase A

Question 2

PKA has many important targets affected by __________.

Answer 2

Phosphorylation

Question 3

Cells are subject to many different messengers from ___ to ____ and this is superimposed on the changing status of the cell itself.

Answer 3

second; second

Question 4

What turns ATP in to cAMP

Answer 4

Adenylyl Cyclase

Question 5

What turns cAMP into AMP?

Answer 5

Phosphodiesterases

Question 6

What does PKA stand for?

Answer 6

Phosphokinase A

Question 7

PKA is activated by _______

Answer 7

cAMP

Question 8

When PKA phosphorates a target protein, they phosphoralate specific _____ ______ ______.

Answer 8

Amino acid residues

Question 9

Does PKA turn on or off target proteins?

Answer 9

They can turn them on or off

Question 10

The effects of PKA are reversed by _______

Answer 10

Phosphotase

Question 11

What can reverse the effects of PKA?

Answer 11

Phosphotases

Question 12

What does PKA phosphorylate on the target proteins?

Answer 12

Specific amino acid residues

Question 13

T or F? PKA can only turn things on?

Answer 13

False, it can turn them on or off

Question 14

Name the targets PKA can affect.

Answer 14

1) Active transport
2) Channel protein
3) ER (protein synthesis, Ca2+ transport)
4) Can act as transcription factor
5) Enzyme, lipid breakdown
6) Enzyme, glycogen breakdown
7) microtubules

Question 15

When cAMP activates PKA, then PKA activates an inactive phophorylase kinase, what is this an example of?

Answer 15

Kinase cascade

Question 16

Can PKA enter the nucleus freely?

Answer 16

No, it’s too large and needs to be transported in

Question 17

What are PLs?

Answer 17

Phospholipases

Question 18

PLs produces different ______ _______ to mediate their effects.

Answer 18

secondary messengers

Question 19

Phosphatidylinositol biphosphate (PIP2) when cleaved by PLC and disassociates into ____ _____

Answer 19

IP3 (Inositol triphosphate) and DAG (Diacylglycerol)

Question 20

T or F? DAG is hydrophilic.

Answer 20

False, hydrophobic

Question 21

When PIP2 is cleaved, what 2nd messenger goes to the ER and opens up a Ca2+ channel?

Answer 21

IP3 (Inositol triphosphate)

Question 22

What needs to happen before PKC is fully activated?

Answer 22

Ca2+ needs to bind with it along with DAG

Question 23

PLA2 will release _______ _____

Answer 23

Arachidonic acid

Question 24

If you take an NSAID, what does it block to prevent you from feeling pain.

Answer 24

Cyclooxygenase (COX1 and COX2)

Question 25

Prostaglandins (PGs) and thromboxanes(TXs) have functions that include _____ and _____.

Answer 25

Inflammation; fever

Question 26

What do Leukotrienes affect?

Answer 26

Immune cell function (acting on leukocytes)

Question 27

"De novo" synthesis of Sphinganine, Sphigosine, and ceramide are initiated by what enzyme?

Answer 27

Serine palmitoyltransferase (SPT)

Question 28

Serine palmitoyltransferase (SPT) can be blocked by what?

Answer 28

SPT Inhibitor

Question 29

Name the types of sphingolipids.

Answer 29

Sphinganine, Sphingosine, Ceramide, Sphingosine 1-P

Question 30

______ are mycotoxins that disrupts sphingolipid messenger functions.

Answer 30

Fumonisins

Question 31

Sphinganine, Sphingosine, Ceramide can either be made by 'De novo" or by recycling of _________ ________ in membranes.

Answer 31

Complex sphingolipids

Question 32

If you tip the scale on the levels of sphingolipids towards Sphingosine 1-P, what will occur?

Answer 32

Anti-apoptotic, proliferation, mitogenesis, inflammation | could lead to cancer

Question 33

If you tip the scale on the levels of sphingolipids towards ceramide, what will will occur?

Answer 33

Apoptosis, cell cycle arrest

Question 34

Omega-3 fatty acids are ____ __________.

Answer 34

Anti-inflammatory

Question 35

Omega-6 fatty acids are ____ __________.

Answer 35

Pro-inflammatory

Question 36

We do not make omega-3's, if we are missing them in our diet, what are they replaced with and why is it bad.

Answer 36

They are replaced with Omega-6 and they are pro-inflammatory

Question 37

Ca2+ is effective on its own as 2ndary messenger, but sometimes it needs to bind with __________.

Answer 37

Calmodulin

Question 38

What does activated MAPkkk do?

Answer 38

Initiate a kinase cascade by phosphorylating MAPkk, which then phosphorylates MAPk, which phosphorylates target proteins that affect important processess like transcription.

Question 39

Inappropriate signaling in LMW G-protein/kinase cascade pathways can result in ________as they are so central in controlling cell growth.

Answer 39

cancer

Question 40

Cell will undergo ______ if it is not told to survive.

Answer 40

Apoptosis

Question 41

PI3-kinase (phosphoinositide 3-kinase) activates Akts (serine/threonine-protein kinase family) by producing PIP3 from PIP2 (DAG/IP3 pathway) by phosphorylation. PIP3 activates protein kinase 1 in turn activates Akts, which releases ______________

Answer 41

Bcl-2

Question 42

During contact-dependent chemical messaging, the delta signal protein reaches the delta receptor of another cell, what happens to the Notch?

Answer 42

The tail is cleaved and migrates to the nucleus. Without this "growth limiting" system, cancer may result