Current Member - Dr. Marie Pointer
Postdoctoral Research Associate
Marie Pointer
Details
Name: Dr. Marie Pointer
Position: Postdoctoral Research Associate
Email: marie.pointer@zoo.ox.ac.uk
Autobiography
I undertook my PhD at the Institute of Ophthalmology, University College London (2000-2004). Here I used molecular genetic techniques to investigate the highly adapted visual system of deep-sea fish. This project ignited a love in evolutionary biology and in adaptation in particular, which led me to take a postdoctoral position in the Department of Zoology at the University of Cambridge. As a member of Dr. Nick Mundy’s group I investigated the genetic basis of melanic and carotenoid coloration in wild birds (2004 – 2010). I joined Murray Edwards College (formerly known as New Hall) as a Junior Research Fellow in 2005 and became a College Lecturer in 2008. I joined the EGI in February 2011 as a Postdoctoral Research Associate in Judith Mank’s group to explore the impact on the genome made by sexual selection and different mating systems. I have been awarded a Fulbright All Disciplines Scholarship to enable me to continue my work on pigmentation. I will be visiting Yale University to study the role of microRNAs in primate pigmentation patterning.
Research Activities
Sexual Selection and the Genome A quick scan of the animal kingdom shows us that there are many differences between males and females, but that not all species share the same level of distinction between the sexes. For example, peacocks and peahens show dramatic sex specific phenotypes in size, coloration, form and behaviour. However, geese and swans are almost impossible to sex without using genetic techniques. These differences suggest that species are under different intensities of sexual selection and this is tightly linked to the mating system of the animal. Monogamous species are under much weaker sexual selection than polygamous. I am interested in investigating how the mating system of a species and hence the strength of sexual selection impacts upon the genome and on gene expression evolution. The Genetics of Carotenoid Coloration A classic example of sexual selection is the conspicuous bright red and yellow coloration often seen in male birds. These colours are often due to the incorporation of carotenoid pigments in developing feathers and scales. The ability to display carotenoid pigments is entirely dependent on obtaining the pigment from the diet and then metabolising, transporting and depositing it within the body. Currently, very little is known about which genes are involved in these processes even though they are prime candidates to be the targets of sexual selection. I am interested in uncovering the genetics of carotenoid coloration and to this end I have constructed and screened a cDNA library from the liver of the Southern Red Bishop (Euplectes orix) for genes involved in the production of bright red canthaxanthin from orange beta-carotene. I am also employing next generation sequencing technology to investigate why zebra finch males and females have different carotenoid profiles within their beak. The Role of MicroRNAs in Pigmentation Patterning The patterning of feathers, scales and fur can be incredibly complex. How stripes, spots and whorls are created is difficult to explain. Numerous pigmentation genes have been identified in mice and the migration of pigmentation cells (melanocytes) during embryogenesis is crucial in determining the patterning of adult mice. However, this does not seem to be the mechanism behind the patterning found in lemurs. Recently, microRNAs have been linked to pigmentation patterning in alpacas and I am looking to investigate how commonly microRNAs are utilised to create pigmentation patterns and whether the patterning seen in lemurs can be explained in this way.
Selected Papers
Walsh, N., Dale, J., McGraw K.J., Pointer, M.A. and Mundy, N.I. (2011) Candidate Genes for Carotenoid Colouration in Vertebrates and Their Expression Profiles in the Carotenoid-Containing Plumage and Bill of a Wild BirdProceedings of the Royal Society In Press. | Read abstract/paper online
Haas, F., Pointer, M. A., Saino, N., Brodin, A., Mundy, N. I. and Hansson, B. (2009) An analysis of population genetic differentiation and genotype-phenotype association across the hybrid zone of carrion and hooded crows using microsatellites and MC1R. Molecular Ecology 18: 294-305. | Read abstract/paper online
Pointer, M. A. and Mundy, N. I. (2008) Testing whether macroevolution follows microevolution: are colour differences among swans (Cygnus) attributable to variation at the MC1R locus. BMC Evolutionary Biology 12(8): 249. | Read abstract/paper online
Pointer, M. A. and Mundy, N. I. (2008) Carotenoid genetics: chicken skin sheds light on carotenoid genetics. Heredity 101(5): 393-394. | Read abstract/paper online
Pointer, M. A., Carvalho, L. S., Cowing, J. A., Bowmaker, J. K. and Hunt, D. M. (2007) The visual pigments of a deep-sea teleost, the pearl-eye Scopelarchus analis. Journal of Experimental Biology 210(16): 2829-2835. | Read abstract/paper online
Pointer, M. A., Cheng, C-H. C., Bowmaker, J. K., Parry, J. W. L., Soto, N., Jeffery, G., Cowing, J. A. and Hunt, D. M. (2005) Adaptations to an extreme environment: retinal organisation and spectral properties of photoreceptors in Antarctic notothenioid fish. Journal of Experimental Biology 208(12): 2363-2376| Read abstract/paper online
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