Lecture 8 - Recovery Flashcards
What is the process for Glut 4 transcription and subsequent translation?
Transcription
- PGC1A activates transcription factor.
- Transcription factor binds to glut 4 gene
- transcription factors reads coding and then produces MRNA
- Glut4 MRNA leaves nucleus, enters cytosol and ribosome
Translation
- MRNA is threaded through ribosome to produce functional Glut 4 protein by adding amino acids to complete chain sequence.
How is the adaptation pathway different endurance training compared to resistance training ?
- Endurance exercise still stimulates sarcolemma macano - sensors however before this signal reaches the mTORC1 pathway it interacts with FAK.
- Upon the reaction with FAK this result in the activation of PGC1a.
- This leads to mitochondrial biogenesis,
- This process can be augmented by exercise changing the energy charge of the cell leading to increases in AMPK, which activates PGC1a.
How can massage lead to mitochondrial biogenesis?
- Massage has been found to activate FAK, and therefore secondary activation of PGC1a.
- PGC1a is a coactivator of transcription factors which result in mitochondrial biogenesis.
What is the process of adaptation?
- Contractile signal is generated by the muscle (Dependent on activity, high frequency for resistance, low for endurance)
- This is detected by primary and secondary messengers (Force producing sensors, energy change, mechanically stimulated proteins, energy sensing proteins)
- This leads to an increase in MRNA of certain genes and proteins.
- If these increase enough this leads to an alteration in the fibre type characteristics.
When should cold water immersion therapy be used ?
- When there is no need to adapt, such as in competition, as it can reduce feeling of doms etc.
What can be an indicator that PGC1A levels have increases within the mitochondria?
- Increases in citrate synthase enzyme activity.
What is elF4E and its purpose?
- Eukaryotic translation initiation factor 4E
- Assists with inserting MRNA into the ribosome to be translated.
What is the process of the mTORC1 pathway?
- Resistance exercise activates macano - sensors within the sarcolemma
- These send signal to mTORC1 complex
- mTORC1 phosphorylates and deactivates binding protein 4EBP1
- 4EBP1 releases elF4E
- elF4E is now free to inset the MRNA into the ribosome
- Alongside the release of elF4E, mTORC1 also phosphorylates and activates P70S6k.
- P70S6k activates the ribosome, thus resulting in protein synthesis, and subsequent hypertrophy.
What is the effect of massage on TNFA?
- Reduces levels of this, thus reducing NFKB levels and decreases the level of protein breakdown.
- This therefore supports the use of massage for treatment post exercise to decrease excessive levels of inflammation.
What happens to PGC1A - MRNA after training over time and haw can this be altered.
- Peaks after training but returns to baseline by 24 hours
- does not peak to the sme level with subsequent session
- Training has to be altered (variation, duration, progressive overload) to resut in an incred MRNA response.
- If there is not a change in training this can result in maladaptation as athletes will have completely adapted to the training.
Which fibre type has the most mTORC1 activity?
- Type 2
How can reduced energy charge of the cell lead to adaption?
- Reduced energy charge of the cell (reduced glycogen content and/or increased ratio of ATP:ADP) activates AMPK (energy sensor).
- This leads to activation of
PGC1α.
-PGC1α is a co-activator of
transcription factors.
-Activation of PGC1α leads to mitochondrial biogenesis and angiogenesis.
What do FAK and AMPK stand for ?
- Focal adhesion kinase
- Activated protein kinase
What happens to MRNA concentrations with exercise and how does this correlate to protein content and exercise performance.
- Per exercise session there is a spike in MRNA concentrations, however the size of this increase decreases per session over time, meaning training has to be done more often to generate adaptation.
- This can be seen with protein content and performance as there are very small increases when the MRNA spikes however these too require time to increase and work simultaneously to the increases inn MRNA content.
What is the transcription process and where does it occur?
Within the nucleus.
- Transcription factor binds to a gene on DNA
- Transcription factor reads the coding on that genre
- Transcription factor then produces MRNA
External to nucleus
- MRNA leaved nucleus and enters cytosol
- Turned into protein by the ribosome
