Department of Zoology

 

Developmental Biology

José Casal

Senior Research Scientist

Email: jec85@cam.ac.uk

Tel.: +44 (0)1223 769015

Epidermal cells of Drosophila are decorated with cuticular hairs. These hairs are always oriented in a particular direction; in the wing all the hairs are pointing distally, an example of what is known as planar polarity. How is this orientation achieved? One possibility is that each cell respondes to a global polarity signal as do Dictyostelium amoeba that are polarised and attracted by a source of cAMP. There is, however, evidence that a global polarity signal cannot be the only cause of polarisation: There are a number of fly genes that when mutated produce an abnormal, disturbed polarity. When a group of cells mutant for one of these genes is made in a otherwise normal fly, wild type cells adjacent to the mutant ones also show a disturbed polarity, even pointing their hairs in the direction opposite to normal. Thus, cells not only may respond to a global polarity system but they are also able to coordinate their polarity with their neighbours. We are trying to understand how this global signalling and the local coordination occur, with the aim of understanding the logical relationship between the different components of planar polarity.

Selected publications

  • Lawrence, P.A., Casal, J. and Struhl, G. (2002) Towards a model of the organisation of planar polarity and pattern in the Drosophila abdomen. Development 129, 2749-2760< /li>
  • Casal, J., Struhl, G and Lawrence, P.A. (2002) Developmental compartments and planar polarity in Drosophila. Current Biology 12, 1189-1198
  • Lawrence, P.A. Casal, J. and Struhl, G. (2004) Cell interactions and planar polarity in the abdominal epidermis of Drosophila. Development 131, 4651-4664
  • Casal, J., Lawrence, P.A. and Struhl, G. (2006) Two separate molecular systems, Dachsous/Fat and Starry night/Frizzled, act independently to confer planar cell polarity. Development 133, 4561-4572
  • Lawrence, P.A., Struhl, G. Casal, J. (2007) Planar cell polarity: one or two pathways? Nature Reviews Genetics 8, 555 - 563
  • Brittle, A. L., Repiso, A., Casal, J., Lawrence, P. A., and Strutt, D. Four- Jointed modulates growth and planar polarity by reducing the affinity of Dachsous for Fat. Curr. Biol., 20, 803–810. (2010).
  • Fabre, C. C. G., Casal, J., and Lawrence, P. A. Mechanosensilla in the adult abdomen of Drosophila: engrailed and slit help to corral the peripheral sensory axons into segmental bundles. Development, 137, 2885–2894. (2010).
  • Repiso, A., Saavedra, P., Casal, J., and Lawrence, P. A. Planar cell polarity: the orientation of larval denticles in Drosophila appears to depend on gradients of Dachsous and Fat. Development, 137, 3411–3415. (2010).