|
|
Dr Jane Carlton PhD, Associate Investigator, The Institute for Genomic Research (TIGR): Comparative genomics of Plasmodium parasites
Dr. Carlton received her Ph.D. in Genetics at the University of Edinburgh in the U.K., and after four years of postdoctoral studies, joined the faculty at the University of Florida in the U.S. After a period of bioinformatics training at the Computational Biology Branch at NCBI, NIH, she moved to her current faculty position at TIGR in 2001. Her main area of research is comparative genomics of parasitic protozoa, in particular species of malaria parasite such as Plasmodium falciparum and rodent Plasmodium species used as model systems, as well as other pathogens such as Theileria and Cryptosporidium. She is currently leading the genome sequencing and comparative analysis of Plasmodium vivax, and of the sexually transmitted human parasite Trichomonas vaginalis at TIGR.
The availability of whole genome sequence data for an increasingly large number of microorganisms is beginning to transform the way that studies into infectious diseases are being carried out. Whereas prior to the genomics revolution investigators worked with a limited number of genes and thus could only perform small-scale studies to determine evolutionary forces on a micro-scale, access to the complete gene complement of an organism will now enable a scaling-up of such analyses to encompass genome-wide studies of gene evolution. The sequencing of eukaryotic genomes has lagged behind sequencing of organisms in the other domains of life, archae and bacteria, but recent initiatives have begun to reverse this trend, especially of pathogenic protozoa that causeserious human disease. Four species of Plasmodium, the infectious agent that causes the disease malaria, are in the closing stages of sequencing, and four have been published, representing one of the largest genome datasets for a single eukaryotic pathogen. Dr. Carlton’s work takes advantage of this large amount of data from a pathogen that is a serious threat to human health, and by using comparative genomics, evolutionary biology and population genetics, aims to address broad evolutionary questions that may be of relevance to other infectious diseases.
Dr Catherine Cosgrove PhD, Postdoctoral Researcher, Edward Grey Institute of Field Ornithology, Department of Zoology, University of Oxford: Evolutionary ecology of avian malaria
Catherine Cosgrove read Zoology at University College London (1995-8), and remained affiliated to UCL during her PhD (1998-2002) at The Natural History Museum (London). Her thesis, supervised by Dr Vaughan Southgate, was on the mating interactions of schistosome blood flukes, and the epidemiological consequences thereof. In October 2002, she switched to studying malaria parasites for her first post-doctoral position, with Professor Karen Day in the Peter Medawar Building for Pathogen Research, University of Oxford. Initially she worked on the global population diversity of the human malaria parasite Plasmodium vivax, but moved on to study avian malaria in UK birds when a collaboration between Prof. Day and Prof. Ben Sheldon of the EGI resulted in a successful grant application to NERC (May 2003). When Prof. Day recently left the UK to take up the Chair of Parasitology at New York University Medical School, she moved to the EGI full-time to continue her work on avian malaria.
The avian malaria project has allowed her to branch into evolutionary ecology, whilst retaining a strong parasitological focus. The biodiversity of avian malaria parasites in Britain, together with the costs conferred upon their host bird populations, is largely unknown. She is currently developing molecular tools to screen birds in Wytham Woods for malaria and to generate a taxonomy for the causative parasites Plasmodium and Haemoproteus. Once she has collated the prevalence data she will be able to look for predictors of infection status, and for the likely consequences of infection.
Professor Karen Day PhD, NYU Department of Medical Parasitology:
Symposium host
Karen Day is the Chair of the Department of Medical Parasitology at NYU’s School of Medicine, the Director of the School’s Institute of Urban and Global Health and the Co-Director of a new, multi-school Masters Program in Global Public Health which will be launched next fall (2006). She runs a multidisciplinary malaria research group that aims to understand the transmission of malaria and to better define control strategies. The group takes laboratory findings, especially genomics, to the field to investigate the epidemiology of malaria as well as the converse i.e. taking observations from the field to the laboratory to identify molecular mechanisms of parasite biology. She has worked extensively in Papua New Guinea, Asia and Africa. Dr. Day’s research integrates the disciplines of epidemiology, immunology, molecular parasitology, genomics, bioinformatics and genetics in population based studies to achieve a better understanding of infectious disease control. One of the projects she is involved in is focused on developing tools (molecular markers) to describe the epidemiology and ecology of bird malaria with the goal of describing the epidemiology of bird malaria in specific transmission situations. She is collaborating in this project with Drs Sheldon and Cosgrove.
Dr Rob Fleischer, Head, Genetics Program, Smithsonian National Museum of Natural History: Trouble in paradise: interactions of invasive diseases and vectors with the native Hawaiian avifauna
Rob Fleischer obtained a B.A. from the University of California at Santa Barbara, and a doctorate from the University of Kansas where he conducted his research on evolutionary and population genetics of introduced house sparrows. He is currently Head of the Genetics Program and a research zoologist at the Smithsonian Institution. The Genetics Program conducts a wide range of projects in evolutionary and conservation genetics and molecular ecology. Since 1987, his primary research has been on evolutionary genetics, systematics and conservation genetics of native and introduced Hawaiian birds and their Plasmodium parasites. He and his Smithsonian Institution collaborators have conducted molecular phylogenetic analyses on many of the endemic taxa in the islands, including the radiation of Hawaiian honeycreepers. Often this has involved analysis of ancient DNA from subfossil bones of many of the extinct and endangered birds. Over the past 10 years, Rob has developed a program that uses genetic and other methods to examine genetic structure and interactions involving an introduced mosquito vector ( Culex quinquefasciatus), a devastating and invasive avian malaria ( Plasmodium relictum), and a number of susceptible native and largely resistant introduced host birds. By understanding this complex system we hope to develop more effective methods to control the impacts of disease on the native birds that yet remain in the forests of Hawaii. The research program has expanded to worldwide surveys of both Plasmosium and Culex, and this has resulted in some surprising findings in relation to the origin of the Hawaiian lineages of these taxa.
Dr Ute Frevert PhD DVM, Associate Professor, NYU Department of Medical Parasitology:
Plasmodium sporozoite migration in the mammalian and avian host
Ute Frevert is an Associate Professor in NYU's Department of Medical Parasitology. She received her D.V.M. in 1982 and her Ph.D. in 1983 from the Freie Universität Berlin, Berlin, Germany, and was a postdoctoral fellow in the Department of Veterinary Biochemistry, Freie Universität Berlin. Dr Frevert works on the interaction between malaria sporozoites and host liver cells.
Mari Kimura, PhD student, Department of Ecology and Evolutionary Biology, Cornell University:
Phylogeographic patterns of avian Plasmodium lineages in the House finch ( Carpodacus mexicanus )
Mari Kimura is a PhD student at the Cornell Lab of Ornithology and the Department of Ecology and Evolutionary Biology. She is interested in the ecology and biogeography of avian blood parasites. So far, she has found that different populations of a single North American bird species harbor different Plasmodium lineages. She is currently conducting experiments on captive birds to investigate the interactions between bird hosts and mosquito vectors that might contribute to these patterns in parasite lineage distribution.
Sarah Knowles, DPhil student, Edward Grey Institute of Field Ornithology, Department of Zoology, University of Oxford:
Evolutionary ecology of avian malaria
Sarah Knowles works with Dr Cosgrove on the evolutionary ecology of avian malaria.
Ellen Martinsen, PhD student, Department of Biology, University of Vermont: Biodiversity of avian malaria parasites
Ellen Martinsen’s interests center on ecology, evolution, and conservation biology. These interests were first kindled through wildlife rehabilitation, which she became involved with at the age of ten. Her undergraduate major was in biology, with a strong emphasis in wildlife ecology. During her undergraduate years, several internships provided experience in field research; these included studies of songbird diversity, demography of forest warblers, and conservation of an endangered Hawaiian thrush. After graduation and a few additional internships in conservation biology and environmental education, she was lured to graduate studies with Joe Schall at the University of Vermont. Her dissertation project examines the diversity and host range of avian blood parasites in the genera Plasmodium, Haemoproteus, and Leucocytozoon. These three genera of parasites have an almost worldwide distribution and are found in most bird families. Her sampling efforts in Vermont from a diversity of habitats include 2,300 birds of 103 species. Additionally, through collaboration with other researchers, hundreds of samples have also been obtained from Massachusetts, California, Israel, and Malaysia, involving 55 additional host species, most harboring infection with one or more parasite genera. Her first research objective is to compare parasite diversity by traditional methods, including morphology and host association, with molecular methods, including single and multi-gene phylogenetic approaches. Additional research objectives include investigation of the distribution of parasite species among their hosts, including the incidence of cospeciation and host switching events. Her research draws from the fields of ornithology and classical parasitology as well as molecular and systematic biology.
Dr Susan Perkins PhD, Assistant Curator, Microbial Systematics and Genomics Division of Invertebrate Zoology, American Museum of Natural History:Systematics of Malaria Parasites: Where We've Been, Where We Are and Where We Should Go
Susan Perkins is an evolutionary biologist, a parasitologist, and a microbiologist. She obtained her Ph.D. in 2000 at the University of Vermont and then moved to the American Museum of Natural History to do a postdoc. She was an assistant professor at the University of Colorado, Boulder from 2001-2004 and then returned to the Museum as an Assistant Curator in 2004. Her research centers on the evolution and biogeography of parasites and exploits the powerful techniques of molecular genetics to pursue issues that were formerly difficult or impossible to resolve in these taxa. Some of her work has also involved the study of the coevolution of parasites and their hosts. Parasite-host systems are particularly intriguing because two or more species coevolve in an antagonisitic fashion, the parasite being completely dependent on its host(s), and the host(s) selected to eliminate the relationship. She has used the malaria parasites ( Plasmodium and related genera), as a model system. These parasites are very diverse (fully 170 species of Plasmodium have been described), world-wide in distribution in many tropical, subtropical, and temperate habitats, infect a great range of vertebrate hosts (birds, mammals, and reptiles), and exhibit a substantial diversity of life history traits. This great diversity of parasite-host systems allows cross-species comparisons and phylogenetic analysis to approach important problems in biology. Molecular techniques have recently been developed for use with human malarial parasites; she has adapted these laboratory methods to study the great range of parasites in Plasmodium, related genera, and more distantly related apicomplexan parasites. Projects include: phylogeny of malaria parasites, gene trees vs. species trees of rodent malaria parasites, evolutionary genetics of Plasmodium rDNA and phylogeography of Caribbean lizard malaria.
Professor Ben Sheldon PhD, Edward Grey Institute of Field Ornithology, Department of Zoology, University of Oxford:
Spatial ecology and individual differences in avian malaria infections
Dr Sheldon’s main interest lies in explaining variation in the wild. Most of his research focuses on wild populations of birds, and on characters that are the target of selection: typically his group studies characters involved in reproduction, or with an intimate link to individual fitness. His group’s research seeks to understand why some individuals are successful, and some are not, or why some behave in one way and others in a different way, by combining approaches from field experiments and observations with quantitative and molecular genetics and population biology. Most of their recent work has been done with small passerine birds that, conveniently, breed in artificial nest-boxes, greatly facilitating their study. In recent years the group has studied populations of blue and great tits Parus caeruleus and P. major near Oxford, with particular focus on the influence of small-scale ecological processes on the behaviour and evolution of these populations. Dr Sheldon’s interest in malaria in birds stems from three sources: (1) for their potential role in population regulation of their avian hosts; (2) from a long-standing research interest in sex ratio variation, for which malaria presents some interesting research possibilities; (3) from pure curiosity.
The potential influence of the environment on the prevalence of haematozoa is little-studied in wild populations. However, understanding this influence is important because wild populations do not live in laboratories, where exposure to infections can be controlled. Environments inhabited by most populations show tremendous spatial variation; if this spatial variation influences the likelihood that an individual is infected, this has important consequences for understanding why some individuals are infected and others are not, and for understanding the influence of parasites on their hosts. Dr Sheldon presents data from a study of several Plasmodium lineages infecting a population of blue tits Parus caeruleus inhabiting a single 370ha woodland near Oxford, UK. While the overall prevalence within this population was c. 30%, there was tremendous spatial variation within the population, with local prevalence ranging from <10% to >70%. In many cases the natal and breeding sites of these birds differed, allowing his group to determine at what stage in life birds contract infections: their spatial data suggests that the vast majority contract them when they are breeding adults, not as naïve juveniles. Spatial analysis of the two commonest Plasmodium lineages showed that they were spatially segregated. These data together suggest that spatial information is critical in understanding patterns of infection, and individual susceptibility, in wild populations, and Dr Sheldon will conclude by exploring how spatial variation of this kind can both mask, and magnify, differences among individuals.
Symposium will take place in the first floor Parasitology Department Seminar Room.
Any questions, please contact Beccy Stafford-Allen (212) 263-4361
|
