I am a PhD candidate in the Nutritional Physiology Group at the St Luke's campus.
The title of my thesis is: Ribosomal turnover and regulation in response to muscle disuse and hypertrophy
MRes Sports and Health Sciences - University of Exeter
BSc (Hons) Sports and Exercise Science - University of Exeter - First Class
Research group links
- Ribosomal profiling
- Skeletal muscle hypertrophy
- Skeletal muscle atrophy
Key publications | Publications by category | Publications by year
Publications by year
(2022). The Ribosome and Skeletal Muscle Anabolism.
The Ribosome and Skeletal Muscle Anabolism
Skeletal muscle hypertrophy is primarily determined by consistent increases in muscle protein synthesis in response to protein and resistance exercise. Any alterations in resistance training, such as load, and protein, such as dose, can impact the degree of muscle protein synthesis and therefore skeletal muscle hypertrophy. Abstract
Non-animal derived sources of protein have increased in popularity due to their ethical and environmental benefits. Previous evidence has shown that non-animal derived protein can stimulate hourly muscle protein synthesis to a lesser extent than animal-derived sources. However, this response can be rescued through increasing the amount of protein consumed. Indeed, two recent studies have shown that by consuming a high amount of daily protein with resistance exercise, the degree of daily muscle protein synthesis and skeletal muscle hypertrophy is unaffected by the type of protein consumed.
Muscle protein synthesis is modulated through sub cellular processes at the level of the ribosome, through either increasing ribosome efficiency (translational efficiency) or ribosomal number (translational capacity). Translational capacity has been thought to underpin the longer-term changes in muscle protein synthesis and skeletal muscle hypertrophy, however little is known about the time course and the transcriptional regulation of translational capacity during skeletal muscle hypertrophy. Therefore, the aim of this thesis is to characterise the abundance and regulation of indirect markers of translational capacity during a short (3 days) and long (10 weeks) of resistance training and
understand if this response is impacted by the type of protein (animal or non-animal derived) consumed.
The first study demonstrated that 3 days of resistance training and high protein consumption lead to a stimulation of all areas of ribosome biogenesis, including rDNA transcription and related signalling, ribosomal proteins and mature rRNA transcripts. However, this did not lead to significant increases in indirect markers of ribosome concentration and other macromolecules (DNA and protein). Additionally, this effect occurred irrespective of the type of protein (animal vs non-animal derived) consumed.
Building upon the first study, the second study measured the regulation and the concentration of the ribosome temporally during 10 weeks of consistent high protein consumption and resistance training. Again, it was found that all areas of ribosome biogenesis were stimulated during the 10 weeks of resistance training and high protein consumption. Indeed, this led to an increase in indirect markers of ribosome concentration at and around 2 weeks of resistance training and this response was maintained for the duration of the study. Similarly to study 1, the transcriptional regulation and concentration of the ribosome was unaffected by the type of protein consumed.
The present thesis reported the novel finding that the transcriptional regulation of all areas of ribosome biogenesis are increased following 3 days and during 10 weeks of high protein consumption and consistent resistance exercise training, irrespective of the type of protein (animal or non-animal) consumed.
Supervision / Group
- Francis Stephens
- Benjamin Wall