How Are Enzymatic Activities Determined? Flashcards
(31 cards)
What do you add into the muscle sample to see how much an enzyme is working win a controlled system?
Acetyl CoA and oxaloacetate
What have human studies shown regarding mitochondrial enzyme activity following endurance exercise ? (Spina et al, 1970)
Rapid increase
What happens to mitochondrial enzyme activity following detraining? (Coyle et al, 1985)
Rapid reduction
What is a strong determinant of number and type of muscle fibres?
Genes
What is fission?
Increase the number of mitochondria to by splitting the mitochondria into smaller mitochondria
What is mitophagy?
Leads out mitochondria that are not functioning
What is thought to be the cause of a decrease in mitochondria health (as we age)?
Disrupted control of the fission and fusion cycle
What proteins are involved in the mitochondrial fusion in the cristae?
Opa 1
Mfn1
Mfn2
What proteins are involved in mitochondrial fission?
Fisb
Drp1
What can lead to a reduction in mitochondrial biogenesis?
-Too much fragmented mitochondria- too much fission
-Mitochondria is too large sending regulatory system into panic causing damage to the mitochondria- too much fusion
What does a decrease in mitochondrial biogenesis cause?
The electron transport chain activity to decrease and cell death increase (apoptosis)
How does endurance exercise lead to skeletal muscle adaptation?
Signal-muscle contraction alters the conc of allosteric factors in skeletal muscle
Sensor- energy sensing proteins respond to alterations in these factors, initiating cellular metabolic processes
Mediator- energy sensing protein target specific transcriptional regulators of metabolism, which in turn leads to an altered fibre type characteristics, mito biogenesis and vascularisation (angiogenesis)
What is one of the most important determinants for how much protein is made up from that gene ?
The amount of RNA made for a gene
What is the promoter region on the RNA?
Region of DNA that signals how much RNA will be made from the gene
What are transcription factors?
Proteins that bind to DNA and change the rate of transcription
What are co-activators?
-Proteins that do not bind to DNA but adjust the activity of transcription factors involved with adaptation
-proteins that promote the assembly of the transcription start site by increasing the association of activators and basal factors
What starts the whole process of transcription?
Transcription factors binding to enhancer regions or DNA and folding of the transcription start sight increase transcription activators
What are repressors?
Regulatory proteins that bind to silencer regions of the promoter and prevent the activation of transcription
What are basal factors?
Transcription factors and co-activators that position RNA polymerase at the transcription start sight increase
What happens first after an acute exercise bout?
Spike in mRNA of a specific gene
What happens later after an acute exercise bout?
Increase in protein conc and enzyme function
What happens last after an acute exercise bout?
Collective lateration of transcriptional control and translation of protein, leading to an increase in performance from muscle metabolism
What are the 1st responders to endurance exercise?
Transcriptional regulators- changes in the amount of mRNA that is being transcribed from the genes due to the exercise
What is complementary DNA generated by?
Reverse transcriptase enzyme
