Lecture 33 Flashcards
What can be said about a satellite cell’s mithochondria density and energy preference?
More dense in mitochondria and have high glycolytic preferences, even with oxygen saturation
What is the pentose pathway, and what is its purpose?
It is a side chain of glycolysis, and is used for nucelotide genesis. Also provides intermediates neccessary for phospholipids and amino acids.
Why do proliferating cells upregulate the pentose pathway?
As they are proliferating, the pentose pathway allows for biomass generation.
What can be said of glycolysis in embryos?
They rely on glycolysis a lot more once they dettach from the uterine wall, activating its side pathways as well (ie. pentose pathway)
Where do quiescent cells source their energy?
From fat, as they are rich in FA metabolism genes
Where do proliferating cells source their energy?
From glucose, as they are rich in glycolytic genes
Do SirT1 (a deacetylase) levels decrease from quiescence to proliferative state?
No, suggesting a decrease in deacetylases isn’t responsible for the decrease in deacetylation, and increased acetylation.
SirT1 cannot act due to NAD+ as it is rapidly used by glycolysis.
Is it possible to backtrack from methylation and deacetylation etc to produce stem cells?
Many combinations of histone and DNA modifications needed to produce specifity.
The reverse is possible, but extremely difficult.
What is metabolic reprogramming?
Altering the cells metabolic state to induce quiescence
What is the difference between culturing cells in glucose versus galactose?
What happens to myogenic expression?
Glucose culture - cells rely on glycolysis
Galactose culture - cells rely on oxidative phosphorylation
Myogenic expression in galactose cultured cells is blunted.
What is TXNIP?
It is highly present in quiescent cells, and absent in proliferating cells.
Inhibits glucose uptake and and the cell cycle stops completely with TXNIP.
