Schistosoma comparative genomics: integrating genome structure, parasite biology and anthelmintic discovery

Abstract

Schistosoma genomes provide a comprehensive resource for identifying the molecular processes that shape parasite evolution and for discovering novel chemotherapeutic or immunoprophylactic targets. Here, we demonstrate how intra- and intergenus comparative genomics can be used to drive these investigations forward, illustrate the advantages and limitations of these approaches and review how post genomic technologies offer complementary strategies for genome characterisation. While sequencing and functional characterisation of other schistosome/platyhelminth genomes continues to expedite anthelmintic discovery, we contend that future priorities should equally focus on improving assembly quality, and chromosomal assignment, of existing schistosome/platyhelminth genomes.

Differences in genomic architecture between two distinct geographical strains of the blood fluke Schistosoma japonicum reveal potential phenotype basis

“…Alignment of probes on the microarray based on mRNA allowed the identification of sub-genomic regions containing previously identified protein coding regions [40]. The publication of Swain et al [27], was used to identify the S. mansoni chromosome corresponding to the S. japonicum genomic supercontig scaffold of interest. Evolutionary Breakpoint Regions associated with these chromosomes were also noted.…”

“…It should be noted that the current study used an updated and expanded microarray redesign, where the majority of genes was not available or did not pass filtering in the original transcriptomic study [18]. Putative in silico assignments of the seven CNV regions to S. mansoni physical mapping reported previously [27] was determined, and Chromosomes 1, 4 and 7 were represented ( Table 2). In addition, previously identified [27] evolutionary breakpoint regions (EBR) were noted ( Table 2) in some of the chromosomes corresponding to the supercontigs identified by CGH.…”

“…Putative in silico assignments of the seven CNV regions to S. mansoni physical mapping reported previously [27] was determined, and Chromosomes 1, 4 and 7 were represented ( Table 2). In addition, previously identified [27] evolutionary breakpoint regions (EBR) were noted ( Table 2) in some of the chromosomes corresponding to the supercontigs identified by CGH.…”

“…The physical structure and karyotype of the chromosomes have been studied in some detail for S. mansoni [26]; however, much less is known regarding the physical map of the S. japonicum genome, and nothing is known of any differences in chromosomal architecture between geographical isolates within the species. Swain and colleagues [27] undertook a comparative genomics study of S. mansoni and S. japonicum and provided chromosomal allocations to the less characterised S. japonicum genomic supercontig scaffolds to the already physically mapped S. mansoni chromosomes, effectively providing a putative in silico karyotype assignment for S. japonicum. In the present study, we provide evidence for differences in gross genomic structure between isolates of S. japonicum from mainland China (SjC) and the Philippines (SjP), and we correlate these genomic differences or copy number variations to well established phenotypic differences.…”

Redox-Assisted Protein Folding Systems in Eukaryotic Parasites

“…Giardia and Entamoeba cause severe enteric diseases (4). Schistosomiasis, sometimes called snail fever, is caused by several species of Schistosoma, commonly recognized as platyhelminths or flukes (79). Although it has a low mortality rate, chronic schistosomiasis affects 200 million people worldwide and damages internal organs.…”