LIFE CYCLE OF THE MODEL TAPEWORM HYMENOLEPIS MICROSTOMA: Juvenile and adult worms reside the bile duct of rodents, and when fully grown (~14 days) their bodies extend into the lumen of the small intestine where Infective larvae are released and expelled with the faeces. When eaten by flour beetles (eg. Tribolium confusum), the onchospereal larvae (aka 'hexacanths') are released from their thin shells and use hooks and secreted enzymes to burrow into the haemocoel, where they metamorphose into infective cysticercoid larvae with fully developed scolices (~7 days). Juvenile worms excyst in the gut of the mouse and spend apx. 3 days in the duodenum and upper small intestine before locating in the bile duct (diagram redrawn and adapted by PD Olson)
Above: optical section of the scolex of Hymenolepis microstoma | confocal images A Gruhl & PD Olson
Below: DIC light microscopy | specimen preparations L Cunningham, images PD Olson
Below: DIC light microscopy | specimen preparations L Cunningham, images PD Olson
UPDATED 4.4.2013
The Hymenolepis microstoma genome published in Nature!
READ NOW / GET THE DATA FROM GeneDB
See Magdalena Zarowiecki and Matt Berriman discussing publication of the first tapeworm genomes
PRESS
The Hymenolepis genome & transcriptome
UPDATED 27.01.2011
Hymenolepis microstoma (Dujardin 1845) Blanchard 1891
(mouse bile duct tapeworm)
Synonyms: Taenia microstoma Dujardin 1845, Rodentolepis microstoma Spasski 1954, Vampirolepis microstoma Spasski 1954
LINEAGE
Eukaryota:Metazoa:Bilateria:Lophotrochozoa:
Platyhelminthes:Neodermata:Cestoda:Eucestoda:
Cyclophyllidea:Hymenolepididae:Hymenolepis
SPECIFIC STRAIN
Our culture of H. microstoma was gifted from Jerzy Behnke (Univ Nottingham) in 2005 who has maintained it for over 30 years, having brought it down from Glasgow, Scotland. The Glasgow culture most likely originated from the Clark P Reid lab in the USA, being sent to Scotland at the same time as cultures of H. diminuta and H. nana. Distribution of this strain since its domestication by the Reid lab in the 1950s has been widespread, and the genome therefore represents a specific strain for which a large body of research has accumulated and that relates to cultures still in use.
SEE ALSO The Wellcome Trust Sanger Institute Hymenolepis microstoma genome
This is a project to sequence the genome and transcriptome of Hymenolepis microstoma, conducted in collaboration with Matt Berriman and his group, and is being led by post-doc Magdalena Zarowiecki. The work is being underwritten by The Wellcome Trust Sanger Institute as part of a larger effort to characterize the genomes of helminths and other parasites of medical or research significance.
Next generation sequencing machines are being used to characterize the genome of our inbred strain of Hymenolepis microstoma (started from a seed culture provided by Jerzy Behnke at Nottingham Univ, UK). The fact that the Echinococcus multilocularis genome and transcriptome are now close to completion--combined with the recent advent of massively-parallel, pyrosequence chemistry detection, has meant that sequencing the genomes of laboratory models such as Hymenolepis can be done cheaply and efficiently.
Although of minor health consequence, rodent-hosted Hymenolepis species (ie. H. diminuta, H. microstoma and H. nana) have been used for in vivo and in vitro laboratory models since the 1960s, and thus much of our basic understanding of tapeworm biology, such as their physiology, biochemistry, ultrastructure and host-parasite interface stems from work on these species. Characterization of their genome will complement that wealth of literature and make their genes available in silico to investigators targeting the molecular basis of cestode biology, especially in adult, strobilate worms for which few alternative models (e.g. Mesocetoides) exist at present.
This initiative also includes Klaus Brehm whose lab at the Univ Würzburg in Germany maintains the strain of Echinococcus multilocularis on which the Sanger genome and transcriptome efforts are based and which will provide a scaffold for the assembly of the Hymenolepis genome.
Klaus, Magdalena and I made a recent visit to Matt and his group in Hinxton to discuss progress on the cestode sequencing projects. Alejandro Sanchez presented preliminary 454 data on the Hymenolepis genome with which they were able to predict the full size to be 118 MB with a G-C content of ~35%, or similar values to the genomes of Echinococcus and Taenia spp. Sequencing is ongoing...
UPDATE 02.02.2010
Magdalena recently joined Matt's team at the Sanger Institute in order to work on the assembly and annotation of the Hymenolepis genome. The combination of 3 x 454 and 1 x Solexa next-gen sequencing is expected to yield 100-fold coverage of the genome. We are presently looking for the means to fund her work with us (watch this space!).
RELATED INFORMATION:
M Zarowiecki, A Sanchez-Flores, N Pouchkina-Stantcheva, N Holroyd, M Berriman & PD Olson
The Hymenolepis genome and transcriptome
(Presented at the Molecular & Cellular Biology of Helminths VI conference, Hydra, Greece Sept 2010)
SEE POSTER PDF (5.2 MB)
The Hymenolepis microstoma genome published in Nature!
READ NOW / GET THE DATA FROM GeneDB
See Magdalena Zarowiecki and Matt Berriman discussing publication of the first tapeworm genomes
PRESS
The Hymenolepis genome & transcriptome
UPDATED 27.01.2011
Hymenolepis microstoma (Dujardin 1845) Blanchard 1891
(mouse bile duct tapeworm)
Synonyms: Taenia microstoma Dujardin 1845, Rodentolepis microstoma Spasski 1954, Vampirolepis microstoma Spasski 1954
LINEAGE
Eukaryota:Metazoa:Bilateria:Lophotrochozoa:
Platyhelminthes:Neodermata:Cestoda:Eucestoda:
Cyclophyllidea:Hymenolepididae:Hymenolepis
SPECIFIC STRAIN
Our culture of H. microstoma was gifted from Jerzy Behnke (Univ Nottingham) in 2005 who has maintained it for over 30 years, having brought it down from Glasgow, Scotland. The Glasgow culture most likely originated from the Clark P Reid lab in the USA, being sent to Scotland at the same time as cultures of H. diminuta and H. nana. Distribution of this strain since its domestication by the Reid lab in the 1950s has been widespread, and the genome therefore represents a specific strain for which a large body of research has accumulated and that relates to cultures still in use.
SEE ALSO The Wellcome Trust Sanger Institute Hymenolepis microstoma genome
This is a project to sequence the genome and transcriptome of Hymenolepis microstoma, conducted in collaboration with Matt Berriman and his group, and is being led by post-doc Magdalena Zarowiecki. The work is being underwritten by The Wellcome Trust Sanger Institute as part of a larger effort to characterize the genomes of helminths and other parasites of medical or research significance.
Next generation sequencing machines are being used to characterize the genome of our inbred strain of Hymenolepis microstoma (started from a seed culture provided by Jerzy Behnke at Nottingham Univ, UK). The fact that the Echinococcus multilocularis genome and transcriptome are now close to completion--combined with the recent advent of massively-parallel, pyrosequence chemistry detection, has meant that sequencing the genomes of laboratory models such as Hymenolepis can be done cheaply and efficiently.
Although of minor health consequence, rodent-hosted Hymenolepis species (ie. H. diminuta, H. microstoma and H. nana) have been used for in vivo and in vitro laboratory models since the 1960s, and thus much of our basic understanding of tapeworm biology, such as their physiology, biochemistry, ultrastructure and host-parasite interface stems from work on these species. Characterization of their genome will complement that wealth of literature and make their genes available in silico to investigators targeting the molecular basis of cestode biology, especially in adult, strobilate worms for which few alternative models (e.g. Mesocetoides) exist at present.
This initiative also includes Klaus Brehm whose lab at the Univ Würzburg in Germany maintains the strain of Echinococcus multilocularis on which the Sanger genome and transcriptome efforts are based and which will provide a scaffold for the assembly of the Hymenolepis genome.
Klaus, Magdalena and I made a recent visit to Matt and his group in Hinxton to discuss progress on the cestode sequencing projects. Alejandro Sanchez presented preliminary 454 data on the Hymenolepis genome with which they were able to predict the full size to be 118 MB with a G-C content of ~35%, or similar values to the genomes of Echinococcus and Taenia spp. Sequencing is ongoing...
UPDATE 02.02.2010
Magdalena recently joined Matt's team at the Sanger Institute in order to work on the assembly and annotation of the Hymenolepis genome. The combination of 3 x 454 and 1 x Solexa next-gen sequencing is expected to yield 100-fold coverage of the genome. We are presently looking for the means to fund her work with us (watch this space!).
RELATED INFORMATION:
M Zarowiecki, A Sanchez-Flores, N Pouchkina-Stantcheva, N Holroyd, M Berriman & PD Olson
The Hymenolepis genome and transcriptome
(Presented at the Molecular & Cellular Biology of Helminths VI conference, Hydra, Greece Sept 2010)
SEE POSTER PDF (5.2 MB)
PUBLICATIONS
Olson PD, M Zarowiecki, F Kiss and K Brehm. 2012. Invited Review: Cestode genomics - progress and prospects for understanding basic and applied aspects of flatworm biology. Parasite Immunology 34:130-150 PDF
Cunningham LC and PD Olson. 2010. Description of Hymenolepis microstoma (Nottingham strain): a classical tapeworm model for research in the genomic era. Parasites & Vectors 3:123
PDF | PubMed
Roche 454 (top) and Solexa next-generation sequencing machines
In silico differential gene expression in Hymenolepis
We are using 454 and Solexa sequencing technologies to examine what genes are expressed differentially in the neck region of tapeworms, where stem cell proliferation and differentiation give rise to immature 'segments'. This technology gives us the ability to rapidly characterize the transcriptomes of different regions of the adult body and of different developmental stages. 'Subtracting' common elements in silico will give us a window into genes associated with specific developmental processes. These data will be informative for a number of investigations, including the determination of spliced leader genes (see below) and for comparitive study with the transcriptome of Echinococcus and other flatworms.
Together with Klaus Brehm and Peter Foster, we are currently piloting this study with adult tissue samples of Hymenolepis microstoma.
UPDATE 13.01.2010
The initial 1/8 scale 454 sequencing results were promising and the project has now been moved to the Sanger Institute and will involve collaborator Matt Berriman and post-doc Magdalena Zarowiecki.
We are using 454 and Solexa sequencing technologies to examine what genes are expressed differentially in the neck region of tapeworms, where stem cell proliferation and differentiation give rise to immature 'segments'. This technology gives us the ability to rapidly characterize the transcriptomes of different regions of the adult body and of different developmental stages. 'Subtracting' common elements in silico will give us a window into genes associated with specific developmental processes. These data will be informative for a number of investigations, including the determination of spliced leader genes (see below) and for comparitive study with the transcriptome of Echinococcus and other flatworms.
Together with Klaus Brehm and Peter Foster, we are currently piloting this study with adult tissue samples of Hymenolepis microstoma.
UPDATE 13.01.2010
The initial 1/8 scale 454 sequencing results were promising and the project has now been moved to the Sanger Institute and will involve collaborator Matt Berriman and post-doc Magdalena Zarowiecki.
Spliced-leader genes and the early evolution of the cestodes
The question of how and from what the tapeworms evolved and how they acquired segmentation directly underpins our work on the molecular mechanisms of their development.
Having reached the limits of the phylogenetic information content in rDNA through previous studies, we are exploring the use of spliced-leader genes for systematic analysis. This work is being conducted by Jan 'Honza' Brabec, PhD student of Tomas Scholz. Together with Klaus Brehm, we are currently advising Honza's thesis.
The question of how and from what the tapeworms evolved and how they acquired segmentation directly underpins our work on the molecular mechanisms of their development.
Having reached the limits of the phylogenetic information content in rDNA through previous studies, we are exploring the use of spliced-leader genes for systematic analysis. This work is being conducted by Jan 'Honza' Brabec, PhD student of Tomas Scholz. Together with Klaus Brehm, we are currently advising Honza's thesis.
DNA Methylation in Flatworms
Genomic methylation is a basic means by which cells regulate gene expression. In a collaboration led by Karl Hoffmann and colleagues, this work aims to explore the status and role of methylation in flatworms.
Genomic methylation is a basic means by which cells regulate gene expression. In a collaboration led by Karl Hoffmann and colleagues, this work aims to explore the status and role of methylation in flatworms.