LICAMM Structural insights into the modulation of heteromeric TRPC1/4/5 channels

Summary

Many human diseases result from abnormalities in the function of ion channels, and many successful therapeutic drugs work by activating or blocking ion channels. Our research focuses on understanding the roles in cardiovascular health and disease of tetrameric cation channels formed by the proteins TRPC1, TRPC4 and TRPC5. In order to study specific TRPC1/4/5 channels in cells, tissues and animal models, specific small molecule modulators with known molecular mechanisms of action are required. Despite more than 15 years of research in the field, the development of such molecules is hindered by the fact that major gaps remain in our knowledge of stoichiometries and structures of biologically relevant TRPC1/4/5 tetramers and their requirements for small-molecule modulation.

We recently discovered that the xanthine-based TRPC1/4/5 modulator Pico145 (the most potent and selective TRPC1/4/5 inhibitor reported to date) binds to a conserved lipid binding site of TRPC5, where it displaces a phospholipid. In this project, we will identify which TRPC1/4/5 tetramers can be formed in cells, and use pharmacological and structural approaches to get insight into their differential modulation by small molecules and physiological factors such as lipids/metal ions.

An example of PhD project design is as follows, but the scope can be tailored to the candidates’ interests:

Year 1
training: cell culture, cloning, biochemical/pharmacological TRPC1/4/5 channel assays
research outcome: identification and functional characterisation of new TRPC1/4/5 heteromers

Year 2
training: construct design for structural studies, membrane protein purification
research outcome: purification of a heteromeric TRPC1/4/5 channel

Year 3
training: cryo-EM grid preparation, data collection and data analysis
research outcome: determination of the high-resolution structure of a heteromeric TRPC1/4/5 channel
This work will enable future development of modulators of specific TRPC1/4/5 tetramers, for use in detailed studies of TRPC1/4/5 biology as well as drug discovery programmes.

References

1. Minard, A.; Bauer, C.C.; Wright, D.J.; Rubaiy, H.; Muraki, K.; Beech, D.J.; Bon, R.S. ‘Remarkable Progress with Small-Molecule Modulation of TRPC1/4/5 Channels: Implications for Understanding the Channels in Health and Disease’. Cells 2018, 7, pii: E52.
2. http://blogs.sciencemag.org/pipeline/archives/2017/06/09/the-great-untangling
3. Wright, D.J.; Simmon, K.J.; Johnson, R.M.; Beech, D.J.; Muench, S.P.; Bon, R.S. ‘Human TRPC5 structures reveal interaction of a xanthine-based TRPC1/4/5 inhibitor with a conserved lipid binding site’. Communications Biology 2020, 3, 704.

A degree in biological sciences, dentistry, medicine, midwifery, nursing, psychology or a good honours degree in a subject relevant to the research topic. A Masters degree in a relevant subject may also be required in some areas of the Faculty. For entry requirements for all other research degrees we offer, please contact us.

Applicants whose first language is not English must provide evidence that their English language is sufficient to meet the specific demands of their study. The minimum requirements for this programme in IELTS and TOEFL tests are: • British Council IELTS - score of 7.0 overall, with no element less than 6.5 • TOEFL iBT - overall score of 100 with the listening and reading element no less than 22, writing element no less than 23 and the speaking element no less than 24.