Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 9/28/2005
Publication Date: 7/20/2005
Citation: Copeland, C.S., Laha, T., Brindley, P.J. 2005. Schistosome long terminal repeat retrotransposons. In: Brindley PJ, Editor. Mobile Genetic Elements in Metazoan Parasites. Austin, Tx: Eurekah Press/Landesbioscience. p. 315-323. Interpretive Summary: Schistosoma mansoni, the African blood fluke, and Schistosoma japonicum, the Asian blood fluke cause schistosomiasis, a serious parasitic disease. These parasitic worms infect humans by directly penetrating skin that has come in contact with contaminated water, making public health based control of the disease difficult. A vaccine would be the perfect solution, but no vaccine is currently available. One of the reasons a vaccine has not been developed is that the schistosome genome is not understood well enough to take full advantage of the powerful molecular tools available for many other diseases. While at Tulane University a scientist now at the Center for Medical, Agricultural and Veterinary Entomology (Gainesville, FL) enhanced understanding of the genomes of S. mansoni and S. japonicum. The human-infecting schistosomes have a large genome, much of it composed of mobile genetic. The structures and evolutionary relationships of these elements, to other elements and to each other, were described. This information should accelerate research that eill lead to the development of an effective vaccine.
Technical Abstract: The human schistosomes, blood flukes of the Genus Schistosoma, have a large genome estimated to be at least 270 megabase pairs (haploid) in size, arrayed on eight pairs (2n = 16) of chromosomes including the Z (male) and W (female) sex chromosomes. The genome appears to include about 14,000 protein encoding genes and a large amount of repetitive sequences. Much of this repetitive component of the schistosome genome is comprised of mobile genetic elements. Of these elements, an expanding number of discrete long terminal retrotransposons have been identified in the past five years. The identity, structure, phylogenetic relationships, and size contributions of these schistosome LTR retrotransposons are reviewed here. These elements include the gypsy-like or Pao/BEL -like retrotransposons Boudicca, Sinbad, fugitive, Saci-1, Saci-2, and Saci-3 from Schistosoma mansoni and Gulliver from Schistosoma japonicum.