This project aims to test whether candidate ageing-related factors affect muscle homeostasis and regeneration in vivo (using a zebrafish model) and in vitro (using a human primary cell culture model). It is becoming clear that although ageing is genetically programmed there are a number of factors that that impact muscle physiology. Our long-term goal is to identify factors that promote an older unhealthy phenotype that can be targeted by available biopharmaceuticals to enhance muscle function in old age. Using zebrafish to visualise tissue and cell behaviour in vivo together with cells isolated from human muscle we will test whether factors identified in ageing muscle affect muscle function and repair.
We have previously identified several factors with age-associated changes in muscle (Lam et al, 2021; Agley et al. 2017). We will test whether these factors alter normal muscle function and repair of muscle in zebrafish using live cell imaging. Gene function will be modified using drugs, gene over-expression and knockdown. Factors that affect muscle repair in zebrafish will then be functionally tested on human muscle stem cells by pharmacological and transient gene over-expression to determine how they affect cell proliferation, differentiation and metabolism.
Techniques and skills:
Confocal and multiphoton microscopy, transgenesis and CRISPR/Cas9 gene manipulation, zebrafish genetics, human muscle cell culture, qRT-PCR
Objectives:
1. Year 1: screen selected ageing factors for effects on muscle in zebrafish and human muscle stem cells
2. Year 2: determine the molecular outcomes from manipulating specific factors
3. Year 3: test specific factors in zebrafish and human ageing models
Figure 1: following focal injury of muscle in zebrafish larvae (white arrow) muscle stem cells (green) respond to injury with some of these expressing a reporter for Notch signalling (red, purple arrows) whereas others do not (yellow arrows).