Dr A Bretman
Prof Lisa Collins
Dr X Harrison
No more applications being accepted
Competition Funded PhD Project (European/UK Students Only)
Humans and other animals play host to an array of microorganisms, including bacteria, which inhabit their guts. This microbial community, or “microbiome”, is now known to perform several functions beneficial to host health, rates of ageing, and lifespan (Vaiserman et al 2017). For example, the gut microbiome has been shown to influence both immune system function and resistance to disease, as well as metabolism and risk of obesity. We also know that some gut bacteria can directly affect mood, and have been linked to mental health disorders such as anxiety and depression. This is why factors that cause these communities to become unbalanced, such as antibiotic treatment, can lead to health problems. There is now a great deal of interest in understanding how changes in the microbiome make otherwise healthy individuals more likely to contract disease, and how manipulating the microbiome in unhealthy individuals might also be useful for treating disease.
Given how important gut microbes are, we need to understand what shapes these communities, how they become dysfunctional, and what consequences this has for host health (Adair and Douglas 2017). A new idea is that there is a great deal of crosstalk between gut and brain, known as the gut-brain axis (Montiel-Castro et al 2013). This crosstalk means that neuro- or psychological stress in the host can alter the microbiome and, in turn, chemicals produced by the gut microbes can influence the host. One very common stressor is the social environment; how many interactions an individual has and what the type of contact alters whether the social environment has positive or negative effects. For example, males of many species are very competitive, so same-sex contact can be generally more negative (stressful) for males than for females. A growing number of studies are showing that social environments can affect animal physiology, behaviour and ultimately lifespan (Leech et al 2017). It may be that what links the social environment with host health is the effect it has on the microbiome. However, whilst various lines of evidence suggest this might be the case there has been no direct experimental study which shows a causal relationship, that is that assessment of the social environment alters the microbiome structure and this affects the host’s health.
Recent work in the Bretman lab has shown that social environments have sex-specific effects on microbiomes in fruit flies (Drosophila melanogaster). This is a very powerful model in many areas of biology, and is used in biomedical research to understand the drivers and consequences of changes in gut microbiomes. We have already shown that same-sex contact makes males age faster and die quicker than it does females, and we have novel evidence that this also alters male microbiomes in older age. We can relatively easily experimentally interfere with key points in the potential pathway from sensing the social environment, to the neurotransmitters that may send information from the brain to the gut, to the microbiome itself, and ultimately establishing how these alter fly health.
A strong undergraduate (and ideally Masters) degree in biology, zoology or genetics is expected. Experience in using insects in a lab, some microbiology techniques and some statistics background would be helpful. However, training will be provided in all techniques relevant for the project. If you are not sure if you have the relevant background please feel free to contact the supervisors to discuss the project.
The Faculty of Biological Sciences is pleased to announce a number of fully-funded PhD studentships to start in Oct 2019, covering academic fees at UK/EU level and providing a stipend at research council rate (£15,009 for 2019-20) for 4 years. Candidates should have, or be expecting, a 2.1 or above at undergraduate level in a relevant subject. A range of projects, spanning the research areas of the faculty, are eligible for funding. Please apply online, clearly stating which project/supervisor you are interested in and including a CV and transcripts.
Adair and Douglas 2017 Current Opinion Microbiology
Leech, Sait and Bretman 2017 Journal of Insect Physiology
Montiel-Castro et al 2013 Frontiers in Integrative Neuroscience
Vaiserman et al 2017 Ageing research Reviews
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FTE Category A staff submitted: 60.90
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