Phospholipids

Question 1

Addition of first FA to G3P

Answer 1

Addition of FA to C1 produces lysophosphatidic acid using GPAT

Question 2

Addition of second FA

Answer 2

Lysophosphatidic Acid to Phosphatidic Acid via AGPAT

Question 3

Removal of Phosphate from C3

Answer 3

Phosphatase to DAG from Phosphatidic Acid

Question 4

Addison of FA to C3

Answer 4

DAG to TAG via DGAT

Question 5

Phospholipid structure

Answer 5

Polar head group
2 non polar tails (14-24C, at least one cis-double bond)
Either Glycerol or sphingosine backbone

Question 6

Difference between Glycolipids, Sphingolipids, Glycerophospholipids, and Phospholipids

Answer 6

Phospholipids can have Glycerol or Sphingosine backbone

Glycerophospholipids = Glycerol backbone

Glycolipids (sphingolipids) = sphingosine backbone, one or more sugars at the terminal hydroxyl group

Question 7

Adding CTP to Phosphatidic acid produces which phospholipids?

Answer 7

Converts it to CDP-DAG

Phosphatidylserine , -inositol, -glyceraldehyde

Question 8

DAG can be converted to which phospholipids?

Answer 8

Phosphatidylcholine and Phosphatidylethanolamine

Question 9

Explain the importance of Phosphatidylinositol

Answer 9

It can be converted into PIP2

PIP2 can be phosphorylated by a kinase triggered by Insulin release, which converts it to PIP3

PIP3 activates a kinase which then activates GLUT4 transporters

Question 10

Where does Phospholipase A1 cleave?

Answer 10

The ester bond on C1

Question 11

Where does Phospholipase A2 cleave?

Answer 11

The ester bond on C2

Question 12

Where does Phospholipase C cleave?

Answer 12

Side of PO4- closer to the backbone

Question 13

Where does Phospholipase D cleave?

Answer 13

Side of PO4 distal to the backbone

Question 14

Phosopholipase C signaling products

Answer 14

DAG - activates PKC

Cleavage of PIP3 to IP3, causes release of Ca2+ from ER