TITLE

Variant Surface Glycoprotein gene repertoires in Trypanosoma brucei have diverged to become strain-specific

AUTHOR(S)
Hutchinson, O Clyde; Picozzi, Kim; Jones, Nicola G; Mott, Helen; Sharma, Reuben; Welburn, Susan C; Carrington, Mark
PUB. DATE
January 2007
SOURCE
BMC Genomics;2007, Vol. 8, p1
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Background: In a mammalian host, the cell surface of African trypanosomes is protected by a monolayer of a single variant surface glycoprotein (VSG). The VSG is central to antigenic variation; one VSG gene is expressed at any one time and there is a low frequency stochastic switch to expression of a different VSG gene. The genome of Trypanosoma brucei contains a repertoire of > 1000 VSG sequences. The degree of conservation of the genomic VSG repertoire in different strains has not been investigated in detail. Results: Eighteen expressed VSGs from Ugandan isolates were compared with homologues (> 40 % sequence identity) in the two available T. brucei genome sequences. Fourteen homologues were present in the genome of Trypanosoma brucei brucei TREU927 from Kenya and fourteen in the genome of T. b. gambiense Dal972 from Cote d'Ivoire. The Ugandan VSGs averaged 71% and 73 % identity to homologues in T. b. brucei and T. b. gambiense respectively. The sequence divergence between homologous VSGs from the three different strains was not random but was more prevalent in the parts of the VSG believed to interact with the host immune system on the living trypanosome. Conclusion: It is probable that the VSG repertoires in the different isolates contain many common VSG genes. The location of divergence between VSGs is consistent with selection for strain-specific VSG repertoires, possibly to allow superinfection of an animal by a second strain. A consequence of strain-specific VSG repertoires is that any vaccine based on large numbers of VSGs from a single strain will only provide partial protection against other strains.
ACCESSION #
28858867

 

Related Articles

  • The Glycosylphosphatidylinositol-PLC in Trypanosoma brucei Forms a Linear Array on the Exterior of the Flagellar Membrane Before and After Activation. Hanrahan, Orla; Webb, Helena; O'Byrne, Robert; Brabazon, Elaine; Treumann, Achim; Sunter, Jack D.; Carrington, Mark; Voorheis, H. Paul // PLoS Pathogens;Jun2009, Vol. 5 Issue 6, p1 

    Bloodstream forms of Trypanosoma brucei contain a glycosylphosphatidylinositol-specific phospholipase C (GPI-PLC) that cleaves the GPI-anchor of the variable surface glycoprotein (VSG). Its location in trypanosomes has been controversial. Here, using confocal microscopy and surface labelling...

  • Analysis of a donor gene region for a variant surface glycoprotein and its expression site in African trypanosomes. LaCount, Douglas J. // Nucleic Acids Research;May2001, Vol. 29 Issue 10, p2012 

    Abstract African trypanosomes evade the immune response of their mammalian hosts by sequentially expressing genes for different variant surface glycoproteins (VSGs) from telomere-linked VSG expression sites. In the Trypanosoma brucei clone whose genome is being sequenced (GUTat 10.1), we show...

  • The Genome Sequence of Trypanosoma brucei gambiense, Causative Agent of Chronic Human African Trypanosomiasis. Jackson, Andrew P.; Sanders, Mandy; Berry, Andrew; McQuillan, Jacqueline; Aslett, Martin A.; Quail, Michael A.; Chukualim, Bridget; Capewell, Paul; MacLeod, Annette; Melville, Sara E.; Gibson, Wendy; Barry, J. Davi; Berriman, Matthew; Hertz-Fowler, Christiane // PLoS Neglected Tropical Diseases;Apr2010, Vol. 4 Issue 4, p1 

    Background: Trypanosoma brucei gambiense is the causative agent of chronic Human African Trypanosomiasis or sleeping sickness, a disease endemic across often poor and rural areas of Western and Central Africa. We have previously published the genome sequence of a T. b. brucei isolate, and have...

  • Tandem gene arrays in Trypanosoma brucei: Comparative phylogenomic analysis of duplicate sequence variation. Jackson, Andrew P. // BMC Evolutionary Biology;2007, Vol. 7, p1 

    Background: The genome sequence of the protistan parasite Trypanosoma brucei contains many tandem gene arrays. Gene duplicates are created through tandem duplication and are expressed through polycistronic transcription, suggesting that the primary purpose of long, tandem arrays is to increase...

  • Characterization of the ligand-binding site of the transferrin receptor in Trypanosoma brucei demonstrates a structural relationship with the N-terminal domain of the variant surface glycoprotein. Salmon, D.; Hanocq-Quertier, J.; Paturiaux-Hanocq, F.; Pays, A.; Tebabi, P.; Nolan, D. P.; Michel, A.; Pays, E. // EMBO Journal;12/15/97, Vol. 16 Issue 24, p7272 

    The Trypanosoma brucei transferrin (Tf) receptor is a heterodimer encoded by ESAG7 and ESAG6, two genes contained in the different polycistronic transcription units of the variant surface glycoprotein (VSG) gene. The sequence of ESAG7/6 differs slightly between different units, so that receptors...

  • Blocking Variant Surface Glycoprotein Synthesis in Trypanosoma brucei Triggers a General Arrest in Translation Initiation. Smith, Terry K.; Vasileva, Nadina; Gluenz, Eva; Terry, Stephen; Portman, Neil; Kramer, Susanne; Carrington, Mark; Michaeli, Shulamit; Gull, Keith; Rudenko, Gloria // PLoS ONE;2009, Vol. 4 Issue 10, p1 

    Background: The African trypanosome Trypanosoma brucei is covered with a dense layer of Variant Surface Glycoprotein (VSG), which protects it from lysis by host complement via the alternative pathway in the mammalian bloodstream. Blocking VSG synthesis by the induction of VSG RNAi triggers an...

  • A Cell-surface Phylome for African Trypanosomes. Jackson, Andrew P.; Allison, Harriet C.; Barry, J. David; Field, Mark C.; Hertz-Fowler, Christiane; Berriman, Matthew // PLoS Neglected Tropical Diseases;Mar2013, Vol. 7 Issue 3, p1 

    The cell surface of Trypanosoma brucei, like many protistan blood parasites, is crucial for mediating host-parasite interactions and is instrumental to the initiation, maintenance and severity of infection. Previous comparisons with the related trypanosomatid parasites T. cruzi and Leishmania...

  • How Does the VSG Coat of Bloodstream Form African Trypanosomes Interact with External Proteins? Schwede, Angela; Macleod, Olivia J. S.; MacGregor, Paula; Carrington, Mark // PLoS Pathogens;12/31/2015, Vol. 11 Issue 12, p1 

    Abstract: Variations on the statement “the variant surface glycoprotein (VSG) coat that covers the external face of the mammalian bloodstream form of Trypanosoma brucei acts a physical barrier” appear regularly in research articles and reviews. The concept of the impenetrable VSG...

  • The genetics of African trypanosomes. TAIT, A. // Onderstepoort Journal of Veterinary Research;Mar2009, Vol. 76 Issue 1, p33 

    The article examines the sexual cycle of Trypanosoma brucei in Africa. It illustrates how genetic analysis can be used as a tool to identify genes of relevance to the disease, as well as its transmission and treatment. It also determines the role of the process in the generation of diversity in...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics