Functional studies of voltage-dependent Ca2+ channels

Professor Annette C. Dolphin PhD, FMedSci
Professor of Pharmacology
Tel: +44 (0) 207 679 3276
Fax: +44 (0) 207 679 0042
email: a.dolphin@ucl.ac.uk
personal webpage
Laboratory of Molecular and Cellular Neuroscience
Andrew Huxley Building
annette

Professor Annette C. Dolphin received her BA in Natural Sciences (Biochemistry) from the University of Oxford and her PhD at the Institute of Psychiatry in London. She held postdoctoral fellowships at the College de France in Paris, and at Yale University, before returning to a post at the National Institute for Medical Research. She then took up a lectureship at St. George's Hospital Medical School, London, and was appointed to the chair of Pharmacology at the Royal Free Hospital School of Medicine, London, in 1990. Following the merger of this Department with the UCL Department in 1997, she moved to the UCL campus. She was elected to the Academy of Medical Sciences in 1999. She has received several prizes including the Sandoz Prize of the British Pharmacological Society (1986), Pfizer Prize in Biology (1991) and the G.L.Brown Prize of the Physiological Society (1994). She is currently an Editor of Pharmacological Reviews.

Lab Members:

  • Laurent Ferron PhD: functions of the tetraspan protein gamma7 in relation to calcium channels
  • Karen Page PhD: calcium channel molecular biology
  • Ivan Kadurin PhD: α2δ biochemistry and alterations in pathology
  • Wojciech Margas PhD: Effects of expression of truncated and mutated calcium channels in native neurons
  • Wendy Pratt: calcium channel molecular biology and laboratory manager
  • Manuela Nieto-Rostro PhD: calcium channel imaging
  • Marianna D’Arco PhD: regulation of calcium channel subunits in DRG neurons
  • Shehrazade Dahimene PhD: Calcium channel trafficking in relation to Episodic ataxia-2

PhD students:

  • Beatrice Lana: novel α2δ splice variants
  • Alexandra Tran-Van-Minh: α2δ subunit trafficking
  • Anita Alvarez-Laviada: electrophysiological studies on calcium channels
  • John Cassidy: expression of N-type calcium channels in neurons
  • Natsuko Macabuag: calcium channel splice variants

Current research:

My group has expertise in the field of neuronal voltage-dependent calcium channels, and our current work has particular reference to the role of accessory subunits, β and α2δ. We use a number of different techniques in our research: involving expression of constructs in primary cultures of neurons or in mammalian cell lines with or without endogenous channels, or Xenopus oocytes. We use patch-clamp electrophysiology to examine macroscopic calcium currents, and we also use a variety of different imaging techniques. We have made a number of antibodies to calcium channel subunits, and are using these, as well as epitope-tagged channels for studies of the molecular epitopes controlling the trafficking and processing of the different calcium channel subunits. We are also using fusion proteins for the biochemical study of calcium channel domain interactions using surface plasmon resonance. The yeast two hybrid technique is also being used to identify novel interactions.

Some specific current projects

  • Regulation of α2δ subunit processing and expression in pathology, including neuropathic pain.
  • Mechanism of action of gabapentin and related drugs, that bind to α2δ subunits.
  • Consequences of the calcium channel mutation in the α2δ-2 subunit in the mouse mutant Ducky that has absence epilepsy and cerebellar ataxia.
  • Calcium channel trafficking in neurons and role of the β subunit.
  • Mechanism of dominant negative suppression of expression by truncated calcium channel α1-subunits such as those resulting from episodic ataxia-2 mutations.
  • Mechanisms of G protein modulation of calcium channels
  • Consequences of novel neuronal calcium channel stargazin-like (gamma 7) subunit expression

Selected Recent papers

  • Davies A, Kadurin I, Alvarez-Laviada A, Douglas L, Bauer CS, Nieto-Rostro M, Pratt, WS and Dolphin AC (2010) The α2δ subunits of voltage-gated calcium channels form GPI-anchored proteins, a post-translational modification essential for function Proc Natl Acad Sci U S A. 107:1654-1659.
  • Page KM, Heblich F, Margas W, Pratt WS, Nieto-Rostro, Chaggar K, Sandhu, K, Davies A and Dolphin AC (2010). The N-terminus is key to dominant-negative suppression of Cav2 calcium channels: implications for episodic ataxia-2. J. Biol. Chem. 285: 835–844.
  • Bauer CS, Nieto-Rostro M, Rahmin W, Tran-Van-Minh A, Ferron L, Douglas L, Kadurin, I, Sri Ranjan Y, Fernandez-Alacid L, Millar NS, Dickenson AH, Lujan R and Dolphin AC (2009). The increased trafficking of the calcium channel subunit α2δ -1 to presynaptic terminals in neuropathic pain is inhibited by the α2δ ligand pregabalin. J Neuroscience 29:4076–4088.
  • Hendrich J, Tran Van Minh A, Heblich F, Nieto-Rostro M, Watschinger K, Striessnig J, Wratten J, Davies A and Dolphin AC (2008) Pharmacological disruption of calcium channel trafficking by the α2δ ligand gabapentin. Proc Natl Acad Sci U S A. 105: 3628–36.
  • Field MJ, Cox PJ, Stott E, Melrose H, Offord J, Su T-Z, Bramwell S, Corradini L, England S, Winks J, Kinloch RA, Hendrich J, Dolphin AC, Webb T and Williams D. (2006) Identification of the α2δ-1 subunit of voltage dependent calcium channels as a novel molecular target for pain mediating the analgesic actions of pregabalin. Proc Natl Acad Sci U S A. 103: 17537-17542.
  • Canti C, Nieto-Rostro M, Foucault I, Heblich F, Wratten J, Richards MW, Hendrich J, Douglas L, Page KM, Davies A, Dolphin AC (2005) The metal-ion-dependent adhesion site in the Von Willebrand factor-A domain of α2δ subunits is key to trafficking voltage-gated Ca2+ channels. Proc Natl Acad Sci U S A. 102: 11230-11235.
  • Viard, P., Butcher, A., Halet, G., Davies, A., Nürnberg, B., Heblich F. and Dolphin, A.C. (2004) PI3K promotes voltage-dependent calcium channel trafficking to the plasma membrane Nature Neuroscience 7: 939-946.
  • Moss, F.J., Viard, P., Davies, A., Bertaso, F., Page, K. M. Graham, A., Cantí, C., Plumpton, M., Plumpton, C., Clare, J. J. and Dolphin A. C. (2002) The novel product of a five-exon stargazin-related gene abolishes CaV2.2 calcium channel expression. EMBO Journal 21: 1514-1523.
  • Raghib, A., Bertaso, F., Davies A., Page K. M., Meir A. Bogdanov, Y. and Dolphin A. C. (2001) Dominant negative synthesis suppression of voltage-gated calcium channel CaV2.2 induced by truncated constructs Journal of Neuroscience 21: 8495 – 8504.
  • Barclay, J. Balaguero, N., Mione, M. Ackerman, S.L., Letts, V.A. Canti, C., Brodbeck, J., Meir, A., Page, K.M., Kusumi, K., Perez-Reyes, E. Lander, E.S., Frankel, W.N., Gardiner, R.M., Dolphin, A.C. and Rees, M. (2001) Ducky mouse phenotype of epilepsy and ataxia is associated with mutations in the Cacna2d2 gene and decreased calcium channel current in cerebellar Purkinje cells. Journal of Neuroscience 21: 6095 -6104.

Selected recent reviews

  • Dolphin AC. (2009) Calcium channel diversity: multiple roles of calcium channel subunits. Current Opinion in Neurobiology 19:237-44.
  • Davies A, Hendrich J, Van Minh AT, Wratten J, Douglas L, Dolphin AC (2007) Functional biology of the α2δ subunits of voltage-gated calcium channels. Trends Pharmacol Sci 28: 220-228.
  • Dolphin, AC. (2006) A short history of voltage-gated calcium channels. Br J Pharmacol. 147 Suppl 1:S56-62.
  • Dolphin A.C. (2003) G protein modulation of voltage-gated calcium channels Pharmacological Reviews 55: 607-627.