LECTURE 31 Flashcards
What additional intermediates does glycolysis supply?
Nucleotides, phospholipids and amino acids for the generation of new biomass
As an embryo develops what energy source does it rely on?
Oxidative phosphorylation to glycolysis
What do quiescent and proliferating satellite cells express?
Q-pax7
P-MyoD
What are the main actions of quiescent and proliferating satellite cells?
Quiescent stem cells: cell adhesion and homeostatic processes
Active/proliferating stem cells: cell proliferation and cell cycle processes
What energy pathways do quiescent and proliferating cells do?
Q-fatty acid oxidation
P-glycolysis
Which cells have more histone acetylation?
Proliferating cells
What happens when you culture cells in glucose or galactose?
Increased ECAR/glycolysis when put in glucose solution, and no real increase when put in galatose
Is MyoD expressed in cells cultured in galactose?
No
What is TXNIP?
Regulator of glycolysis, inhibits glucose uptake and conversion to G6P
Where is TXNIP highly expressed?
Quiescent cells
What happens when TXNIP is over expressed?
Decrease in glycolysis/ECAR, stop cell cycle, decline in MyoD expression
What can G0 lead on to?
- Senescence - happens with aging, satellite cell loses ability to enter cell cycle (irreversible),
- Differentiation (irreversible),
- Quiescence (reversible)
What does PKM do?
Regulates last step of glycolysis, PPP - pyruvate
What does PKM1 do?
Promotes movement of PPP to pyruvate for entry into mitochondria – high levels of PKM1 associated with increased reliance on oxidative phosphorylation (high levels in quiescent cell population)
What does PKM2 do?
Has a lower affinity for PPP – so it build up and glycolysis intermediates build up for generation of new biomass (high levels in proliferative cell population)
