RESEARCH
Our activities are divided into basic research of parasite biology, and associated translational activities, such as disease intervention and molecular epidemiology. We study parasites from several genera, including Trypanosoma, Plasmodium, Leishmania and Trichomonas. Although the parasites differ greatly from each other, we focus on core processes, many of which show common mechanisms in the different parasites.
Our basic research, shown in the triangle, feeds into our translational activities, in the diamonds
BASIC RESEARCH
All our basic research projects fall into one of the topics of growth, infection or diversity. Here are some examples of current programmes, with more information revealed by clicking the title of each. Click 
to link to each investigator's research pages.
Antigenic variation as a major force of infection by trypanosomes.
Conditional translational repression as a core gene regulatory mechanism in Plasmodium.
Response to stress in Plasmodium falciparum as a survival mechanism.
Use of genetic mapping to identify genes responsible for important trypanosome traits.
Roles of proteolytic mechanisms in growth and virulence of Leishmania.
Functional analysis of the Plasmodium protein kinase repertoire.
Perturbing the trypanosome’s metabolome.
DNA recombination, repair and antigenic variation in African trypanosomes.
Understanding molecular mechanisms underlying cytokinesis in Trypanosoma brucei.
TRANSLATIONAL ACTIVITIES
Current translational activities in WCMP include:
Biological testing leading to clinical testing.
Generation of attenuated live vaccines.
Strategies for blocking parasite transmission.
BASIC RESEARCH: PROJECT DETAILS
Antigenic variation as a major force of infection by trypanosomes. Antigenic variation is a major force in infection by trypanosomes, having led to major adaptations in the parasite genome and in cellular structure and function. The variation process also influences the development of parasitaemia, leading to chronicity of infection. We have developed a model that predicts that the pattern of growth in infection is driven by two parasite factors. We have also shown that the mechanisms and extent of antigenic variation during chronic infection are much more extensive and diversifying than previously thought, raising a new theory for the function of the process in transmission and persistence in the field. We aim now to test this theory and to dissect the mechanisms and consequences of the hyperevolution and expression of antigen genes.
Dave Barry, Wellcome Trust Principal Research Fellowship.
Conditional translational repression as a core gene regulatory mechanism in Plasmodium. Conditional Translational Repression (CTR) has been discovered that is essential for complete sexual differentiation and subsequent development of Plasmodium. Aims now are to determine structure and function of the dynamic CTR complex, understand the roles of intracellular signalling pathways in the CTR process and how the external and internal cellular environments stimulate/repress translation through the sexual cycle. The functional role of the repressed transcriptome will be assessed. On a broader scale, we shall examine whether CTR operates in other parasitic protozoa, and whether elements of CTR in humans are associated with medical syndromes.
Andy Waters, Wellcome Trust Principal Research Fellowship.
Response to stress in Plasmodium falciparum as a survival mechanism. In erythrocytes, Plasmodium falciparum encounters enhanced oxidative stress, resulting largely from its digestion of haemoglobin, and thus its redox balance is fragile. We have now identified several anti-oxidant defence molecules of the parasite and shown that they are important for its survival. We aim now to carry this work forward by characterizing in detail mechanisms for sensing and responding to this stress.
Sylke Muller, Wellcome Trust Senior Research Fellowship.
Use of genetic mapping to identify genes responsible for important trypanosome traits. We have developed genetic mapping of important trypanosome traits. By developing assays for various traits that differ between the two parents of a cross and analyzing co-segregation of genome markers and the given trait, we are in a position to identify regions of the trypanosome genetic map that contain trait-associated genes. Our aim is to fine-map traits down to a resolution of just a few genes, so that candidate genes can then be identified, isolated and characterized, which in turn will help reveal trait mechanisms. Traits that will be analyzed this way include human infectivity, drug resistance, anaemia (a cardinal symptom of trypanosomiasis), organ pathology and aspects of immune responses. Andy Tait, Mike Turner and Annette MacLeod, Wellcome Trust programme grant, Wellcome Trust Career Development Fellowship.
Roles of proteolytic mechanisms in growth and virulence of Leishmania. Cysteine peptidases play an important role in the pathogenicity of parasitic protozoa such as Leishmania, which contains multiple highly active enzymes, many of which are stage-regulated. We have characterised mutants lacking cysteine peptidases, which has revealed that the enzymes are virulence factors and have important roles in the host-parasite interaction. Future studies will define the trafficking pathway of cysteine peptidases to the lysosome, the function of the lysosome and the mechanism of release of virulence factors from Leishmania amastigotes. Investigations are also in progress to investigate the mechanisms by which Leishmania cysteine peptidases and their natural inhibitors affect the host immune system.
Jeremy Mottram and Graham Coombs, Wellcome Trust and MRC programme grants.
Functional analysis of the Plasmodium protein kinase repertoire. We have bioinformatically characterized the kinome of Plasmodium falciparum and identified novelties including the absence of some protein kinases that are considered key in mammals, and the presence of novel kinases, some of which are Apicomplexan-specific. These differences from the host auger well for development of specific drugs, and screenings are being run at the labs of several academic or industrial collaborators. We are now systematically characterizing the kinome biochemically and genetically, identifying biological roles and assessing essentiality, as a first step towards validation as drug targets, and have initiated a phosphoproteomics approach to identify substrates of the kinases. Specific aims include elucidating the organisation and function of protein phosphorylation-dependent signalling pathways in Plasmodium and its host erythrocyte, and identifying specific kinase inhibitors as lead molecules in the context of antimalarial drug discovery.
Christian Doerig, INSERM Unit programme grant.
Perturbing the trypanosome’s metabolome. We have pioneered ultra-high resolution, ultra- high mass accuracy mass spectrometry approaches to delineate the metabolomes of protozoa including Leishmania and Trypanosoma brucei. Metabolomics aims to identify all low molecular weight metabolites within a given system. Using Fourier transform mass spectrometry we have identified thousands of metabolites in the trypanosome’s metabolome. Some are expected based on classical genome-based reconstructions of the metabolome. Vast numbers of metabolite, however, could not have been predicted from such reconstructions. Of particular interest is the construction of networks of metabolite, based either on putative chemical connectivity, or on correlation changes to abundance as a function of perturbation. The perturbations that we have focused on are environmental changes that stimulate differentiation and also drug induced changes to the metabolome. Through this latter approach we are seeking targets for trypanocidal and leishmanicidal drugs.
Mike Barrett, BBSRC-ANR Systems Biology grant; SULSA Systems Biology theme studentship, BBSRC CASE Award with Pfizer.
DNA recombination, repair and antigenic variation in African trypanosomes. We are exploring the genetic mechanisms and controls of the DNA recombination reactions that give rise to antigenic variation. Although a discrete, dedicated recombination machinery might seem like a sensible strategy to effect VSG recombination, the available experimental evidence suggests that homologous recombination, normally employed to repair general DNA damage, is used. In this sense, antigenic variation appears comparable to other forms of locus-directed genome rearrangements found throughout evolution. Nevertheless, much remains to be learned. For example, is unregulated genetic recombination sufficient for VSG gene switching, or do trypanosomes encode factors that direct the reactions? A number of pathways of homologous recombination have been described in other organisms; is the same true in trypanosomes, and do all contribute to VSG recombination? Can we define the trypanosome genes that control and execute VSG recombination? Are there novel modifications of the trypanosome recombination and repair systems to accommodate the demands made by antigenic variation?
Richard McCulloch, MRC and Wellcome Trust project grants.
Understanding molecular mechanisms underlying cytokinesis in Trypanosoma brucei.
We have identified several proteins required for cytokinesis in bloodstream form T. brucei. The functions of these proteins differ in the procyclic form, where one appears to be required for accuracy of furrowing, and the other is essential for basal body duplication. Work in the lab is now focussing on identifying binding partners and substrates for these proteins, with a longer term aim of being able to link cytokinesis regulators in pathways. We are also analysing the function and biochemistry of a number of other putative cytokinesis regulators, with a view to identifying novel drug targets.
Tansy Hammarton, MRC Career Development Fellowship
TRANSLATIONAL ACTIVITIES: PROJECT DETAILS
Target validation for drug development, protein expression and enzymatic assay development suitable for High Throughput screens.
We have a long tradition of using genetic manipulation to validate potential drug targets within our fundamental hypothesis-driven research, primarily for Plasmodium, Leishmania and Trypanosoma brucei, targeting enzymes in cell signalling pathways (protein kinases/phosphatases), protein turnover (peptidases), redox metabolism and intermediary metabolism. We also run the MRC-funded protein purification facility and Scottish Higher Education Funding Council (SHEFC)-funded Envision multiplate system, to produce active recombinant protein and develop enzyme assays suitable for High Throughput Screens (HTS; fluorescence, fluorescence polarisation, colorimetric etc). Strong collaborative ties with screening centres (e.g. Drug Discovery Unit, University of Dundee; MRC Technology, NIMR) provide opportunities for HTS and hit-to-lead chemistry.
Biological testing leading to clinical testing.
We collaborate with chemists and structural biologists, in Glasgow and beyond, to develop lead compounds suitable for further stages of drug development. We have developed a variety of cell-or whole animal-based screens for assessing the biological efficacy of lead compounds arising from drug development projects.
Generation of attenuated live vaccines.
We are generating attenuated live vaccines by genetic manipulation of Leishmania and Plasmodium. As parasite genetic manipulation is used extensively in several of our research programmes, mutants can be evaluated for vaccine potential.
Molecular epidemiology.
The genome sequencing of a range of protozoan pathogens has enabled the development of a series of highly polymorphic markers for trypanosomes, Theileria spp, Babesia spp and Cryptosporidium. We have applied a recently developed simple, highly sensitive sampling technique to address both fundamental population genetic questions and more translational goals relating to the impact and transmission of live vaccines, the origin of disease outbreaks and the detection and spread of drug resistance. Our research will build on these developments and focus on using population genetics as a tool to define loci under selection, the development of more sensitive diagnostic assays (for infection and drug resistance) and the evaluation of novel loci implicated in drug resistance, particularly in livestock and human trypanosomiasis.
Strategies for blocking parasite transmission.
Blockade of parasite transmission to or from insect vectors has great potential as a means to control subsequent human and animal infection. We are characterising aspects of the biology of transmission forms of parasites that are generally conserved and critical to parasite success. The deployment of stored mRNA stocks by the fertilised Plasmodium zygote is essential for transmission and controlled by kinase-mediated signal transduction pathways. We have established, or are developing, whole cell assays based upon specialised reporter parasite lines. Such assays will be applied towards identification of compounds that may act to stimulate host immune responses blocking transmission, or prevent zygote development in the newly-infected mosquito.