Glycerolipids Flashcards
What are the components of glycerolipids?
- Glycerol Backbone
- 2 fatty acids
- Polar head group
What kind of lipids are plasmalogens and Platelet Activating Factor?
Either Glycerolipids
What types of lipids are typically found on the inner leaflet of the cell membrane?
Glycerol Lipids
What kinds of lipids are typically found on the outer leaflet (ECM side) of the plasma membrane?
Sphingolipids and Glycolipids
What type of glycerolipids plays the role of storing and transporting fatty acids?
TAGs
What enzyme cleaves TAG and DAG to make 2-MG?
Pancreatic Lipase
Where does a TAG get converted to FAs and 2-MG?
intestinal Lumen
Where does TAG get resynthesized?
Enterocyte cytoplasm
What is the job of MTP?
To get TAGs and Lipids into the ER
What is the mode of movement for exogenous TAGs?
Chylomicrons
How much energy is required to make a TAG from glycerol and fatty acids in the liver?
4 ATP, less energy is needed because the liver has glycerol kinase
How much energy is required to make a TAG from DHAP and fatty acids in adipose tissue?
3 ATP, 1 NADH (~2.5 ATP), more energy is required because glycerol cannot be directly used
T or F: about 1/2 of what fat cells release in FA-albumin comes back in to get reesterified?
True
What would happen if you were born with PEPCK that was more efficient than wild type PEPCK?
You would be fat because it would allow for OAA to be turned into pyruvate and pushed back up through gluconeogenesis until DHAP was formed and utilized in the TAG synthesis pathway
What is phosphatitidic acid?
- Glycerol with FAs at position 1 and 2 and Phosphate at 3
When does LPL increase on the adipocyte cell surface?
when insulin is high in the fed state
Besides LPL, what else is responsive to insulin that aids in TAG synthesis in adipocytes?
GLUT 4 gets upregulated to allow for more glucose to enter to make DHAP
Suppose the gene for ApoCII were knocked out, what would you expect to see in this rat?
lots of fat in the blood
What cleaves the phosphodiester bond between glycerol and the PO4?
Phospholipase C, this makes DAG (think about signaling pathway)
What cleaves the Fatty acid off of the 1 position of glycerol?
Phospholipase A1
What cleaves the Fatty acid off of the 2 position of glycerol?
Phospholipase A2
What cleaves the head group from the phosphate?
Phospholipase D
What are the two different methods of converting phosphotidic acid to Glycerophospholipids?
- Add activated headgroup to DAG
- Activate DAG then add headgroup
***Both processes require a CTP
T or F: certain headgroups like Serine and Ethanolamine can be reversibly interchanged
True
