Bloom busters: understanding how phytoplankton defend against grazers. PhD in Biosciences (NERC GW4 + DTP) Ref: 3664
About the award
Dr Katherine Helliwell, Department of Biosciences, College of Life and Environmental Sciences, University of Exeter; Marine Biological Association
Dr Glen Wheeler , Marine Biological Association
Location: University of Exeter, Streatham Campus, Exeter EX4 4QJ
This project is one of a number that are in competition for funding from the NERC GW4+ Doctoral Training Partnership (GW4+ DTP). The GW4+ DTP consists of the GW4 Alliance of research-intensive universities: the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus five unique and prestigious Research Organisation partners: British Antarctic Survey, British Geological Survey, Centre for Ecology & Hydrology, the Natural History Museum and Plymouth Marine Laboratory. The partnership aims to provide a broad training in the Earth, Environmental and Life sciences, designed to train tomorrow’s leaders in scientific research, business, technology and policy-making. For further details about the programme please seehttp://nercgw4plus.ac.uk/
For eligible successful applicants, the studentships comprises:
- An stipend for 3.5 years (currently £15,009 p.a. for 2019/20) in line with UK Research and Innovation rates
- Payment of university tuition fees;
- A research budget of £11,000 for an international conference, lab, field and research expenses;
- A training budget of £3,250 for specialist training courses and expenses.
- Travel and accomodation is covered for all compulsory DTP cohort events.
- No course fees for courses run by the DTP
We are currently advertising projects for a total of 10 studentships at the University of Exeter
Students who are resident in EU countries are eligible for the full award on the same basis as UK residents. Applicants resident outside of the EU (classed as International for tuition fee purposes) are not eligible for DTP funding. Residency rules are complex and if you have not been resident in the UK or EU for the 3 years prior to the start of the studentship, please apply and we will check eligibility upon shortlisting.
Marine phytoplankton contribute almost half of global primary production, and represent a critical sink for rising atmospheric CO2. Biotic pressures such as grazing and viral infection are major sources of phytoplankton mortality, causing the termination of algal blooms, and shaping the structure of planktonic communities. Top-down biotic controls on phytoplankton productivity are thus critical drivers of global carbon fluxes in the ocean. To evade predation, phytoplankton can evoke a range of defense mechanisms: modifying cell size, shape or chain length, and/or producing harmful toxins to reduce palatability and predation encounter rates. These adaptive responses can have cascading impacts on food-web structure and ecosystem health. Despite this, mechanisms enabling important phytoplankton taxa to sense and respond to grazing, are largely unknown. The aim of this project is to employ an established state-of-the-art molecular tool-kit to examine the mechanisms controlling adaptive responses of phytoplankton to predators, and in turn determine the impact of such defenses on grazer behavior.
Project Aims and Methods
A major barrier to our understanding of phytoplankton-grazer interactions has been the lack of a fully genetically-tractable model system. This is essential to examine the genetic underpinnings of phytoplankton defence mechanisms, and their impact on grazer biology. This project will build on our established model algal species Phaeodactylum, with the annelid worm Platynereis that consumes Phaeodactylum in its early larval stages. This system offers a novel opportunity to study the basic molecular mechanisms governing phytoplankton-grazer interactions, and subsequently elucidate their broader impact on aquatic ecosystem functioning.
1. Determine the impact of Platynereis grazing on diatom cell physiology (growth, photosynthetic efficiency, morphology) and metabolism
2. Examine how diatom cells sense and respond to grazing pressure
- Fluorescence microscopy with diatom strains expressing biosensors (e.g. to measure calcium) will enable real-time signalling responses to be visualised in response to grazer presence and/or diffusible cues.
- Generation/examination of mutant lines via established CRISPR-Cas9 approaches will enable the molecular mechanisms underpinning such signalling responses to be elucidated.
3. Characterise the impact of diatom grazer defence mechanisms (e.g. toxin production) on predator behaviour (such as motility) and grazing rate
4. Examine the specificity and conservation of defence mechanisms underpinning diatom-grazer interactions:
- The conservation of defensive mechanisms to different grazers (e.g. copepods, predatory protists), and between different ecologically-important diatom species will be examined.
An enthusiastic, motivated individual interested in how molecular mechanisms in the cell impact ecosystem level processes, with a relevant biological sciences degree (marine biology, microbiology, plant sciences). Further enquiries are encouraged and can be made to the leading supervisor (Dr Katherine Helliwell, email@example.com).
CASE or Collaborative Partner
The student will spend significant time at the collaborative partner institute the Marine Biological Association. The MBA is a world-leading marine research institute with a vibrant postgraduate learning experience. The student will have access to a wide-array of unique research resources, including state-of the-art imaging facilities, access to the Plymouth Culture Collection of marine algae, the MBA research vessel, and MBA training opportunities e.g. in advanced microscopy. Opportunities to engage in broader activities (e.g. science communication and public engagement) are also encouraged.
The successful candidate with gain training a range of approaches for examining algal biology, including algal cell culture and conducting physiological experiments. Training will also be in cutting-edge cell and molecular biology approaches including CRISPR-Cas9 gene knock-out, genetic transformation of diatoms, cloning, live-cell imaging (e.g. confocal and epifluorescence microscopy). In addition skills will be gained in bioinformatics (mining genome and metatranscriptome datasets), with opportunities to attend the University of Exeter Bioinformatics Worskshop.
Professional development, including in core verbal (preparing and giving effective conference talks and poster presentations) and written communication (paper writing, report and thesis writing), research and analytical skills (e.g. data presentation, image analysis and quantification approaches) will also be given.
References / Background reading list
 Amato et al., Grazer-induced transcriptomic and metabolomic response of the chain-forming diatom Skeletonema marinoi. The ISME Journal, 12: 1594–1604 (2018)
 Helliwell et al., Alternative Mechanisms for Fast Na+/Ca2+ Signalling in Eukaryotes via a Novel Class of Single-Domain Voltage-Gated Channels. Current Biology, 29, 1503–1511 (2019)
 Selander et al., Copepods drive large-scale trait-mediated effects in marine plankton. Science Advances. 5(2) (2019)
Applicants should have obtained, or be about to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK. Applicants with a Lower Second Class degree will be considered if they also have Master’s degree. Applicants with a minimum of Upper Second Class degree and significant relevant non-academic experience are encouraged to apply.
All applicants would need to meet our English language requirements by the start of the project http://www.exeter.ac.uk/postgraduate/apply/english/.
How to apply
In the application process you will be asked to upload several documents. Please note our preferred format is PDF, each file named with your surname and the name of the document, eg. “Smith – CV.pdf”, “Smith – Cover Letter.pdf”, “Smith – Transcript.pdf”.
- Letter of application outlining your academic interests, prior research experience and reasons for wishing to undertake the project.
- Transcript(s) giving full details of subjects studied and grades/marks obtained. This should be an interim transcript if you are still studying.
- If you are not a national of a majority English-speaking country you will need to submit evidence of your current proficiency in English.
You will be asked to name 2 referees as part of the application process, however we will not expect receipt of references until after the shortlisting stage. Your referees should not be from the prospective supervisory team.
If you are shortlisted for interview, please ensure that your two academic referees email their references to the firstname.lastname@example.org, 7 days prior to the interview dates. Please note that we will not be contacting referees to request references, you must arrange for them to be submitted to us by the deadline.
References should be submitted by your referees to us directly in the form of a letter. Referees must email their references to us from their institutional email accounts. We cannot accept references from personal/private email accounts, unless it is a scanned document on institutional headed paper and signed by the referee.
All application documents must be submitted in English. Certified translated copies of academic qualifications must also be provided.
The closing date for applications is 1600 hours GMT Monday 6 January 2020. Interviews will be held between 10 and 21 February 2020. For more information about the NERC GW4+ DPT please visit https://nercgw4plus.ac.uk
If you have any general enquiries about the application process please email email@example.com. Project-specific queries should be directed to the lead supervisor.
During the application process, the University may need to make certain disclosures of your personal data to third parties to be able to administer your application, carry out interviews and select candidates. These are not limited to, but may include disclosures to:
- the selection panel and/or management board or equivalent of the relevant programme, which is likely to include staff from one or more other HEIs;
- administrative staff at one or more other HEIs participating in the relevant programme.
Such disclosures will always be kept to the minimum amount of personal data required for the specific purpose. Your sensitive personal data (relating to disability and race/ethnicity) will not be disclosed without your explicit consent.
|Application deadline:||6th January 2020|
|Value:||£15,009 per annum for 2019-20|
|Duration of award:||per year|
|Contact: PGR Enquiriesfirstname.lastname@example.org|