Development of Organelle Targeted Ligands to Delineate GPCR signalling University of Birmingham in United Kingdom

G protein-coupled receptors (GPCRs) are a large family of integral membrane proteins comprising seven transmembrane a-helical domains that relay extracellular signals to the interior of the cell. GPCRs are involved in multiple physiological process including cell growth, neurotransmission, metabolism & immune response; they can misfunction in disease and consequently have served as fertile targets for drug discovery and development (approx. 30% of all drugs target this family). Extensive research has characterized GPCR signalling at the cell surface, however more recent studies pioneered by our team using advanced microscopy methods have established that GPCRs can signal from multiple intracellular compartments such as early endosomes or the Golgi.1, 2 Such intracellular signalling can have distinct effects from cell-surface signalling, even when the same effectors and second messengers are activated. However, delineating the function of specific GPCRs in distinct organelles is difficult. This project will develop and harness state of the art chemical biology tools (Fig. 1) and advanced optical methods to control and monitor GPCR signalling in space and time and evaluate the functional consequences of GPCR signalling from intracellular compartments.

The project will benefit from access to the state-of-the-art expertise and facilities for advanced microscopy of the Centre of membrane Proteins and Receptors (COMPARE).3 We will focus on FFA44 and NTSR1 as model GPCRs. Building on our groups expertise in development of covalent chemical probes5 and protein labelling methods,6 a range of small-molecule agonists/antagonists will be armed with: (i) organelle localization sequences, (ii) light/enzyme responsive uncaging groups (iii) photoswitchable groups and (iv) covalent warheads for conjugation to organelle specific protein fusions with Halo/Snap-Tag (Fig. 1).7 This will facilitate spatiotemporally controlled agonism/antagonism of the target GPCRs, in that a range of tools will be developed to either localize to a specific organelle (e.g. early endosomes) or, can be activated in the target organelle to exert their affect upon their target GPCR. These powerful tools will thus allow us to dissect out the functional significance of specific intracellular GPCR signalling events and separate these from cell surface signalling, which could pave the way to a new generation of more selective and better tolerated drugs.

You will join a vibrant, diverse and group of researchers to gain skills and knowledge in chemical biology in its broadest sense, and, participate in our wider collaborative research.

Specific multidisciplinary skills include: synthetic chemistry, structural molecular biology and advanced imaging; it will harness cutting edge computational tools (incl. image analyses), giving the student computational and quantitative bioscience capabilities.

Funding notes:

Entry requirements: The candidate should normally have, or expect to receive, a first or upper second (2.1) class Masters degree (or equivalent). The interdisciplinary nature of this research means that we welcome applications from students with backgrounds in any biological, chemical, and/or physical science, who are interested in using their skills in addressing biological questions. Please contact Prof Andy Wilson ( [email protected] ) Prof Davide Calebiro ( [email protected] ) for further details about this project. For more information on our group’s current research activity see: https://ajwilsonresearch.com/

English language requirements: The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent (e.g. TOEFL, PTE etc.). The test must be dated within two years of the start date of the course in order to be valid.

Funding on offer BBSRC Midlands Integrative Biosciences Training Partnership Studentships offer a comprehensive support package, including fees (the cost of the UK fee rate), a tax-free annual stipend (in academic year 2023-24 this was £18,622.00), a travel and conference budget, a generous consumables budget, and the use of a MacBook Pro for the duration of the programme.

References:

1. D. Calebiro, European Journal of Endocrinology, 2021, 184, R41-R49.

2. D. Calebiro, V. O. Nikolaev, M. C. Gagliani, T. de Filippis, C. Dees, C. Tacchetti, L. Persani and M. J. Lohse, PLoS Biol., 2009, 7, e1000172.

3. J. Grimes, Z. Koszegi, Y. Lanoiselée, T. Miljus, S. L. O’Brien, T. M. Stepniewski, B. Medel-Lacruz, M. Baidya, M. Makarova, R. Mistry, J. Goulding, J. Drube, C. Hoffmann, D. M. Owen, A. K. Shukla, J. Selent, S. J. Hill and D. Calebiro, Cell, 2023, 186, 2238-2255.e2220.

4. E. Tripp, S. L. O’Brien, G. Smith, A. Boufersaoui, J. Roberts, J. Pike, J. Correia, T. Miljus, D. A. Tennant, B. D. Hudson, G. Milligan, Z. Gerhart-Hines, T. W. Schwartz and D. Calebiro, bioRxiv, 2023, DOI: 10.1101/2023.07.28.550805, 2023.2007.2028.550805.

5. T. Ueda, T. Tamura, M. Kawano, K. Shiono, F. Hobor, A. J. Wilson and I. Hamachi, J. Am. Chem. Soc., 2021, 143, 4766-4774.

6. J. E. Horne, M. Walko, A. N. Calabrese, M. A. Levenstein, D. J. Brockwell, N. Kapur, A. J. Wilson and S. E. Radford, Angew. Chem. Int. Ed., 2018, 57, 16688-16692.

7. G. V. Los, L. P. Encell, M. G. McDougall, D. D. Hartzell, N. Karassina, C. Zimprich, M. G. Wood, R. Learish, R. F. Ohana, M. Urh, D. Simpson, J. Mendez, K. Zimmerman, P. Otto, G. Vidugiris, J. Zhu, A. Darzins, D. H. Klaubert, R. F. Bulleit and K. V. Wood, ACS Chem. Biol., 2008, 3, 373-382.