Cytosine methylation regulates oviposition in the pathogenic blood fluke Schistosoma mansoni

Geyer, Kathrin K.; López, Carlos M. Rodríguez; Chalmers, Iain W.; Munshi, Sabrina E.; Truscott, Martha; Heald, James K.; Wilkinson, M. J.; Hoffmann, Karl F.

doi:10.1038/ncomms1433

Cited by 113 publications

(160 citation statements)

References 57 publications

Supporting

Mentioning

141

Contrasting

Unclassified

Order By: Relevance

“…1B). Finally, we also used our data for a detailed analysis of the Schistosoma forkhead gene that had previously been reported to be methylated in a Dnmt2-dependent manner (23). Our results failed to reveal any evidence for DNA methylation at the previously analyzed region (Fig.…”

Section: Resultscontrasting

confidence: 44%

Dnmt2-dependent methylomes lack defined DNA methylation patterns

Raddatz

Guzzardo

Olova

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

214

212

View full text Add to dashboard Cite

Several organisms have retained methyltransferase 2 (Dnmt2) as their only candidate DNA methyltransferase gene. However, information about Dnmt2-dependent methylation patterns has been limited to a few isolated loci and the results have been discussed controversially. In addition, recent studies have shown that Dnmt2 functions as a tRNA methyltransferase, which raised the possibility that Dnmt2-only genomes might be unmethylated. We have now used whole-genome bisulfite sequencing to analyze the methylomes of Dnmt2-only organisms at single-base resolution. Our results show that the genomes of Schistosoma mansoni and Drosophila melanogaster lack detectable DNA methylation patterns. Residual unconverted cytosine residues shared many attributes with bisulfite deamination artifacts and were observed at comparable levels in Dnmt2-deficient flies. Furthermore, genetically modified Dnmt2-only mouse embryonic stem cells lost the DNA methylation patterns found in wild-type cells. Our results thus uncover fundamental differences among animal methylomes and suggest that DNA methylation is dispensable for a considerable number of eukaryotic organisms.

show abstract

Section: Resultscontrasting

confidence: 44%

Dnmt2-dependent methylomes lack defined DNA methylation patterns

Raddatz

Guzzardo

Olova

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

214

212

View full text Add to dashboard Cite

show abstract

“…The E. granulosus genome had 48 DLC members (compared to 35 in Schistosoma japonicum and 29 in Schistosoma mansoni), whereas 4-7 were found in the 4 nematodes. We identified 49 cadherins in the E. granulosus genome, similar to the numbers found in schistosomes (51-65) but more than in nematodes (12)(13)(14)(15)(16)(17)(18) (Supplementary Table 22b). Cadherins belong to a class of type 1 transmembrane proteins that have important roles in cell recognition and adhesion.…”

Section: Domain Families Gained In E Granulosusmentioning

confidence: 48%

“…5). Cytosine methylation in the schistosome genome regulates oviposition 12 , but the higher CpG content in worms might hint that such methylation occurs much less frequently in these organisms than in mammals. We found only one DNA (cytosine-5)-methyltransferase gene (gene symbol, DNMT3B; gene ID: EG_07014; KO identifier, K00558) and one methyl-CpG-binding domain gene (MBD; EG_02905; K11590) in the E. granulosus genome (Supplementary Table 13), whereas ten DNMT genes are present in humans.…”

Section: Genome Sequencing and Annotationmentioning

confidence: 99%

The genome of the hydatid tapeworm Echinococcus granulosus

et al. 2013

View full text Add to dashboard Cite

A r t i c l e sThe dog tapeworm E. granulosus is one of a group of medically important parasitic helminths of the family Taeniidae (Platyhelminthes; Cestoda; Cyclophyllidea) that infect at least 50 million people globally 1 . Its life cycle involves two mammals, including an intermediate host, usually a domestic or wild ungulate (humans are accidental intermediate hosts) and a canine-definitive host, such as the domestic dog. The larval (metacestode) stage causes hydatidosis (cystic hydatid disease; cystic echinococcosis), a chronic cyst-forming disease in the intermediate (human) host. Currently, up to 3 million people are infected with E. granulosus 2,3 , and, in some areas, 10% of the population has detectable hydatid cysts by abdominal ultrasound and chest X-ray 4,5 .E. granulosus has no gut, circulatory or respiratory organs. It is monoecious, producing diploid eggs that give rise to ovoid embryos, the oncospheres. Strobilization is a notable feature of cestode biology, whereby proglottids bud distally from the anterior scolex, resulting in the production of tandem reproductive units exhibiting increasing degrees of development. A unique characteristic of the larvae (protoscoleces, PSCs) within the hydatid cyst is an ability to develop bidirectionally into an adult worm in the dog gastrointestinal tract or into a secondary hydatid cyst in the intermediate (human) host, a process triggered by bile acids 6 . Another distinct feature of E. granulosus is its capacity to infect and adapt to a large number of mammalian species as intermediate hosts, which has contributed to its cosmopolitan global distribution.Here we report the sequence and analysis of the E. granulosus genome. Comprising nine pairs of chromosomes 7 , it is one of the first cestode genomes to be sequenced and complements the recent publication by Tsai et al. 8 of a high-quality genome for Echinococcus multilocularis (the cause of alveolar echinococcosis), together with draft genomes of three other tapeworm species including E. granulosus. Our study provides insights into the biology, development, differentiation, evolution and host interaction of E. granulosus and has identified a range of drug and vaccine targets that can facilitate the development of new intervention tools for hydatid treatment and control. Cystic echinococcosis (hydatid disease), caused by the tapeworm E. granulosus, is responsible for considerable human morbidity and mortality. This cosmopolitan disease is difficult to diagnose, treat and control. We present a draft genomic sequence for the worm comprising 151.6 Mb encoding 11,325 genes. Comparisons with the genome sequences from other taxa show that E. granulosus has acquired a spectrum of genes, including the EgAgB family, whose products are secreted by the parasite to interact and redirect host immune responses. We also find that genes in bile salt pathways may control the bidirectional development of E. granulosus, and sequence differences in the calcium channel subunit EgCa v b 1 may be associated with praziquantel sens...

show abstract

“…This process revealed that low levels (∼2.5% of CpGs, based upon a genome-wide average) of modification are present, although we cannot strictly distinguish based upon our analysis between cytosine methylation and other modifications, such as hydroxymethylation. Notably, DNA methylation was not detected in S. mediterranea (37) and there are conflicting reports for S. mansoni (38,39).…”

Section: Resultsmentioning

confidence: 99%

Genome and transcriptome of the regeneration-competent flatworm, Macrostomum lignano

Wasik

Gurtowski

Zhou

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

100

138

View full text Add to dashboard Cite

The free-living flatworm, Macrostomum lignano has an impressive regenerative capacity. Following injury, it can regenerate almost an entirely new organism because of the presence of an abundant somatic stem cell population, the neoblasts. This set of unique properties makes many flatworms attractive organisms for studying the evolution of pathways involved in tissue self-renewal, cellfate specification, and regeneration. The use of these organisms as models, however, is hampered by the lack of a well-assembled and annotated genome sequences, fundamental to modern genetic and molecular studies. Here we report the genomic sequence of M. lignano and an accompanying characterization of its transcriptome. The genome structure of M. lignano is remarkably complex, with ∼75% of its sequence being comprised of simple repeats and transposon sequences. This has made high-quality assembly from Illumina reads alone impossible (N50 = 222 bp). We therefore generated 130× coverage by long sequencing reads from the Pacific Biosciences platform to create a substantially improved assembly with an N50 of 64 Kbp. We complemented the reference genome with an assembled and annotated transcriptome, and used both of these datasets in combination to probe gene-expression patterns during regeneration, examining pathways important to stem cell function.F latworms belong to the superphylum Lophotrochozoa, a vast assembly of protostome invertebrates (1, 2) (Fig. 1A). The evolutionary relationships within this clade are poorly resolved and the specific position of flatworms is currently debated (3, 4). Flatworms have attracted scientific attention for centuries because of their astonishing regenerative capabilities (5, 6), as well as their ability to "degrow" in a controlled way when starved (7). As far back as the early 1900s, Thomas Morgan recognized the potential of flatworms and conducted a number of fascinating regeneration experiments on planarian flatworms before his focus shifted to Drosophila genetics (8).Macrostomum lignano is (Fig. 1B), a free-living, regenerating flatworm isolated from the coast of the Mediterranean Sea. M. lignano is an obligatorily cross-fertilizing simultaneous hermaphrodite (9) that belongs to Macrostomorpha, whereas the other often-studied freeliving flatworms and human parasitic flatworms all belong to clades that are potentially more derived (less ancestral) in comparison with Macrostomorpha (2) (Fig. 1C).Many flatworms can regenerate nearly their entire body or amputated organs. This regenerative capacity is thought to be attributable to the presence of somatic stem cells, termed neoblasts (10, 11). In Schmidtea mediterranea (planarian flatworm), even a single transplanted neoblast has the ability to rescue, regenerate, and change the genotype of a fatally irradiated worm (12). M. lignano can regenerate every tissue, with the exception of the head region containing the brain (13,14).Neoblasts in M. lignano ( Fig. 1 D and E), in contrast to most vertebrate somatic stem cells, are plentiful, making up about ...

show abstract

Cytosine methylation regulates oviposition in the pathogenic blood fluke Schistosoma mansoni

Cited by 113 publications

References 57 publications

Dnmt2-dependent methylomes lack defined DNA methylation patterns

Dnmt2-dependent methylomes lack defined DNA methylation patterns

The genome of the hydatid tapeworm Echinococcus granulosus

Genome and transcriptome of the regeneration-competent flatworm, Macrostomum lignano

Contact Info

Product

Resources

About