The evolution of extreme nitrogen uptake in plants
Dr G Chomicki
Prof S Paterson
Prof K Lindsey
No more applications being accepted
Competition Funded PhD Project (European/UK Students Only)
Background: The speed at which plants can take up nitrogen is a key limitation to plant growth rate. Genetic engineering to increase nitrogen use efficiency has met limited success because plants can modify their nitrogen uptake efficiency mechanisms in function of the available nitrogen level. Recently, a farming symbiosis involving ants that cultivate, fertilize, live in and defend epiphytic plants (Squamellaria) has been discovered in the Fiji Islands. In this symbiosis, farming ants have practised a form of ‘precision agriculture’ for millions of years, wherein they actively and exclusively provide nitrogen-rich faeces on particular plant structures called warts, which have evolved an extreme nitrogen uptake rate. This project aims to decipher how these symbiotic plants have this extreme uptake efficiency despite high nitrogen concentration.
Aims and Methodology: The student will conduct gene expression and comparative genomic analyses to identify candidate genes linked to nitrogen uptake in Squamellaria. Physiological assays will be used to determine the kinetics of nitrogen absorption in vivo, using greenhouse-cultivated plants. Immunolocalisation and tools to transiently down-regulate gene expression will be used to target candidate genes. Reverse genetics will be used to test the effect of Squamellaria nitrogen transporters in Arabidopsis both under their native as well as root-specific promoters.
Timetable: Year 1: Complete transcriptomic and genomic analyses and start physiological assays; clone nitrogen transporters from Squamellaria. Year 2: Perform transient gene editing assays in Squamellaria, finish physiological assays and transform constructs with Squamellaria nitrogen transporters in Arabidopsis. Year 3: Perform nitrogen fertilization growth assays to compare growth rate and yield of the different transgenic lines and write up thesis.
HOW TO APPLY
Applications should be made by emailing [Email Address Removed] with a CV (including contact details of at least two academic (or other relevant) referees), and a covering letter – including whatever additional information you feel is pertinent to your application; you may wish to indicate, for example, why you are particularly interested in the selected project and at the selected University. Applications not meeting these criteria will be rejected.
In addition to the CV and covering letter, please email a completed copy of the Additional Details Form (Word document) to [Email Address Removed]. A blank copy of this form can be found at: https://www.nld-dtp.org.uk/how-apply.
Informal enquiries may be made to [Email Address Removed]
Please note that the closing date for applications is Monday 18th May at 12noon.
This is a 4 year BBSRC studentship under the Newcastle-Liverpool-Durham DTP. The successful applicant will receive research costs, tuition fees and stipend (£15,009 for 2019-20). The PhD will start in October 2020. Applicants should have, or be expecting to receive, a 2.1 Hons degree (or equivalent) in a relevant subject. EU candidates must have been resident in the UK for 3 years in order to receive full support. Please note, there are 2 stages to the application process.
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