Lecture 12. Gluconeogenesis Flashcards
What are some classic gluconeogenic precursors ?
- Glycerol
- Amino acids
- Lactate
What is the mitochondrial conundrum ?
Pyruvate needs to be converted to oxaloacetate but it cannot pass through the mitochondrial membranes. Instead it is converted to malate which is transported into the mitochondria where it is converted back to oxaloacetate
What type of control is there of glycolysis and gluconeogenesis
REM reciprocal control
Where does the energy supply for gluconeogenesis come from
Fatty acid oxidation
What 10 things control gluconeogenesis ?
- High glucagon/insulin ratio
- Enzyme abundance
- Tissue specificity
- Compartmentalisation eg. mitochondria to cytosol to endoplasmic reticulum
- Enzyme kinetics
- Thermodynamic favourability
- Substrate cycling
- Covalent modification
- Transcription
- Substrate supply
What inhibits phosphodiesterase
Caffeine
What breaks down cyclic AMP ?
Phosphodiester
What does cyclic AMP do ?
Activate protein kinase A
Where is glucagon and insulin released ?
Glucagon is released by alpha cells of pancreas. Insulin is released by beta cells of pancreas
Where does the conversion of glucose-6-phosphate to glucose occur ?
Only in the liver and kidney and happens in the lumen of the endoplasmic reticulum
What are triacylglycerides ?
The storage form of fat in white adipose tissue
What parts of the cell does gluconeogenesis occur ?
cytoplasm, mitochondria, endoplasmic reticulum
What are some classic gluconeogenic precursors ?
- Glycerol
- Amino acids
- Lactate
What and how drives gluconeogenesis ?
Fatty acid oxidation by producing ATP
What type of control or regulation does gluconeogenesis have ?
Multilayered
