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author:("ferriman, M.")
1.  Characterization of the antimicrobial peptide attacin loci from Glossina morsitans 
Insect molecular biology  2008;17(3):293-302.
The antimicrobial peptide Attacin is an immune effector molecule that can inhibit the growth of gram-negative bacteria. In Glossina morsitans morsitans, which serves as the sole vectors of African trypanosomes, Attacins also play a role in trypanosome resistance, and in maintaining parasite numbers at homeostatic levels in infected individuals. We characterized the attacin encoding loci from a Bacterial Artificial Chromosome (BAC) library. The attacin genes are organized into three clusters. Cluster 1 contains two attacin (attA) genes located in head-to-head orientation, cluster 2 contains two closely related genes (attA and attB) located in a similar transcriptional orientation, and cluster 3 contains a single attacin gene (attD). Coding and transcription regulatory sequences of attA and attB are nearly identical, but differ significantly from attD. Putative AttA and AttB have signal peptide sequences, but lack the pro domain typically present in insect Attacins. Putative AttD lacks both domains. Analysis of attacin cDNA sequences shows polymorphisms that could arise either from allelic variations or from the presence of additional attacin genomic loci. Real time-PCR analysis reveals that attA and attB expression is induced in the fat body of flies per os challenged with Escherichia coli and parasitized with trypanosomes. In the midgut, expression of these attacins is similarly induced following microbial challenge, but reduced in response to parasite infections. Transcription of AttD is significantly less relative to the other two genes, and is preferentially induced in the fat body of parasitized flies. These results indicate that the different attacin genes may be differentially regulated.
PMCID: PMC2656931  PMID: 18477243
attacin loci; attacin expression; Glossina morsitans morsitans; trypanosome
2.  The genome of the simian and human malaria parasite Plasmodium knowlesi 
Nature  2008;455(7214):799-803.
Plasmodium knowlesi is an intracellular malaria parasite whose natural vertebrate host is Macaca fascicularis (the ‘kra’ monkey); however, it is now increasingly recognized as a significant cause of human malaria, particularly in southeast Asia1,2. Plasmodium knowlesi was the first malaria parasite species in which antigenic variation was demonstrated3, and it has a close phylogenetic relationship to Plasmodium vivax​4, the second most important species of human malaria parasite (reviewed in ref. 4). Despite their relatedness, there are important phenotypic differences between them, such as host blood cell preference, absence of a dormant liver stage or ‘hypnozoite’ in P. knowlesi, and length of the asexual cycle (reviewed in ref. 4). Here we present an analysis of the P. knowlesi (H strain, Pk1(A+) clone5) nuclear genome sequence. This is the first monkey malaria parasite genome to be described, and it provides an opportunity for comparison with the recently completed P. vivax genome4 and other sequenced Plasmodium genomes6-8. In contrast to other Plasmodium genomes, putative variant antigen families are dispersed throughout the genome and are associated with intrachromosomal telomere repeats. One of these families, the KIRs9, contains sequences that collectively match over one-half of the host CD99 extracellular domain, which may represent an unusual form of molecular mimicry.
PMCID: PMC2656934  PMID: 18843368
3.  Extensive chromosome rearrangements distinguish the karyotype of the hypovirulent species Candida dubliniensis from the virulent Candida albicans 
Candida dubliniensis and Candida albicans, the most common human fungal pathogen, have most of the same genes and high sequence similarity, but C. dubliniensis is less virulent. C. albicans causes both mucosal and hematogenously disseminated disease, C. dubliniensis mostly mucosal infections. Pulse-field electrophoresis, genomic restriction enzyme digests, Southern blotting, and the emerging sequence from the Wellcome Trust Sanger Institute were used to determine the karyotype of C. dubliniensis type strain CD36. Three chromosomes have two intact homologues. A translocation in the rDNA repeat on chromosome R exchanges telomere-proximal regions of R and chromosome 5. Translocations involving the remaining chromosomes occur at the Major Repeat Sequence. CD36 lacks an MRS on chromosome R but has one on 3. Of six other C. dubliniensis strains, no two had the same electrophoretic karyotype. Despite extensive chromosome rearrangements, karyotypic differences between C. dubliniensis and C. albicans are unlikely to affect gene expression. Karyotypic instability may account for the diminished pathogenicity of C. dubliniensis.
PMCID: PMC2277252  PMID: 17719250
4.  The genome of the social amoeba Dictyostelium discoideum 
Eichinger, L. | Pachebat, J.A. | Glöckner, G. | Rajandream, M.-A. | Sucgang, R. | Berriman, M. | Song, J. | Olsen, R. | Szafranski, K. | Xu, Q. | Tunggal, B. | Kummerfeld, S. | Madera, M. | Konfortov, B. A. | Rivero, F. | Bankier, A. T. | Lehmann, R. | Hamlin, N. | Davies, R. | Gaudet, P. | Fey, P. | Pilcher, K. | Chen, G. | Saunders, D. | Sodergren, E. | Davis, P. | Kerhornou, A. | Nie, X. | Hall, N. | Anjard, C. | Hemphill, L. | Bason, N. | Farbrother, P. | Desany, B. | Just, E. | Morio, T. | Rost, R. | Churcher, C. | Cooper, J. | Haydock, S. | van Driessche, N. | Cronin, A. | Goodhead, I. | Muzny, D. | Mourier, T. | Pain, A. | Lu, M. | Harper, D. | Lindsay, R. | Hauser, H. | James, K. | Quiles, M. | Babu, M. Madan | Saito, T. | Buchrieser, C. | Wardroper, A. | Felder, M. | Thangavelu, M. | Johnson, D. | Knights, A. | Loulseged, H. | Mungall, K. | Oliver, K. | Price, C. | Quail, M.A. | Urushihara, H. | Hernandez, J. | Rabbinowitsch, E. | Steffen, D. | Sanders, M. | Ma, J. | Kohara, Y. | Sharp, S. | Simmonds, M. | Spiegler, S. | Tivey, A. | Sugano, S. | White, B. | Walker, D. | Woodward, J. | Winckler, T. | Tanaka, Y. | Shaulsky, G. | Schleicher, M. | Weinstock, G. | Rosenthal, A. | Cox, E.C. | Chisholm, R. L. | Gibbs, R. | Loomis, W. F. | Platzer, M. | Kay, R. R. | Williams, J. | Dear, P. H. | Noegel, A. A. | Barrell, B. | Kuspa, A.
Nature  2005;435(7038):43-57.
The social amoebae are exceptional in their ability to alternate between unicellular and multicellular forms. Here we describe the genome of the best-studied member of this group, Dictyostelium discoideum. The gene-dense chromosomes encode ~12,500 predicted proteins, a high proportion of which have long repetitive amino acid tracts. There are many genes for polyketide synthases and ABC transporters, suggesting an extensive secondary metabolism for producing and exporting small molecules. The genome is rich in complex repeats, one class of which is clustered and may serve as centromeres. Partial copies of the extrachromosomal rDNA element are found at the ends of each chromosome, suggesting a novel telomere structure and the use of a common mechanism to maintain both the rDNA and chromosomal termini. A proteome-based phylogeny shows that the amoebozoa diverged from the animal/fungal lineage after the plant/animal split, but Dictyostelium appears to have retained more of the diversity of the ancestral genome than either of these two groups.
PMCID: PMC1352341  PMID: 15875012
5.  Adult midgut expressed sequence tags from the tsetse fly Glossina morsitans morsitans and expression analysis of putative immune response genes 
Genome Biology  2003;4(10):R63.
An expressed sequence tag (EST) project on the adult tsetse midgut, the major organ system for establishment and early development of trypanosomes has been undertaken. The most notable block of genes upregulated in response to trypanosome challenge are a series of Toll and Imd genes and a series of genes involved in oxidative stress responses.
Tsetse flies transmit African trypanosomiasis leading to half a million cases annually. Trypanosomiasis in animals (nagana) remains a massive brake on African agricultural development. While trypanosome biology is widely studied, knowledge of tsetse flies is very limited, particularly at the molecular level. This is a serious impediment to investigations of tsetse-trypanosome interactions. We have undertaken an expressed sequence tag (EST) project on the adult tsetse midgut, the major organ system for establishment and early development of trypanosomes.
A total of 21,427 ESTs were produced from the midgut of adult Glossina morsitans morsitans and grouped into 8,876 clusters or singletons potentially representing unique genes. Putative functions were ascribed to 4,035 of these by homology. Of these, a remarkable 3,884 had their most significant matches in the Drosophila protein database. We selected 68 genes with putative immune-related functions, macroarrayed them and determined their expression profiles following bacterial or trypanosome challenge. In both infections many genes are downregulated, suggesting a malaise response in the midgut. Trypanosome and bacterial challenge result in upregulation of different genes, suggesting that different recognition pathways are involved in the two responses. The most notable block of genes upregulated in response to trypanosome challenge are a series of Toll and Imd genes and a series of genes involved in oxidative stress responses.
The project increases the number of known Glossina genes by two orders of magnitude. Identification of putative immunity genes and their preliminary characterization provides a resource for the experimental dissection of tsetse-trypanosome interactions.
PMCID: PMC328452  PMID: 14519198
6.  Expression of chemosensory proteins in the tsetse fly Glossina morsitans morsitans is related to female host-seeking behaviour 
Insect Molecular Biology  2011;21(1):41-48.
Chemosensory proteins (CSPs) are a class of soluble proteins present in high concentrations in the sensilla of insect antennae. It has been proposed that they play an important role in insect olfaction by mediating interactions between odorants and odorant receptors. Here we report, for the first time, the presence of five CSP genes in the tsetse fly Glossina morsitans morsitans, a major vector transmitting nagana in livestock. Real-time quantitative reverse transcription PCR showed that three of the CSPs are expressed in antennae. One of them, GmmCSP2, is transcribed at a very high level and could be involved in olfaction. We also determined expression in the antennae of both males and females at different life stages and with different blood feeding regimes. The transcription of GmmCSP2 was lower in male antennae than in females, with a sharp increase in 10-week-old flies, 48 h after a bloodmeal. Thus there is a clear relationship between CSP gene transcription and host searching behaviour. Genome annotation and phylogenetic analyses comparing G. morsitans morsitans CSPs with those of other Diptera showed rapid evolution after speciation of mosquitoes.
PMCID: PMC3664020  PMID: 22074189
chemosensory protein; tsetse fly; gene expression; trypanosomiasis; nagana

Results 1-6 (6)