1 / 21

Class Trematoda:

PHYLOGENETIC RELATIONSHIPS OF THE GENUS PSILOTREMA ( P. oschmarini , P. acutirostris , P. simillimum ) BASED ON 28S rDNA SEQUENCES Atopkin D.M. Institute of Biology and Soil Sciences, Far Eastern Branch of Russian Academy of Sciences. Class Trematoda:.

abetty
Download Presentation

Class Trematoda:

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PHYLOGENETIC RELATIONSHIPS OF THE GENUS PSILOTREMA (P. oschmarini, P. acutirostris, P. simillimum) BASED ON 28S rDNA SEQUENCESAtopkin D.M.Institute of Biology and Soil Sciences, Far Eastern Branch of Russian Academy of Sciences

  2. Class Trematoda: • 2 Subclasses: Aspidogastrea and Digenea • 12 Orders • ~ 90 Families • ~ 7000 Species

  3. Life cycle of trematodes Metacercaria Parthenogenetic generation Cercaria Adolescaria Adult worm Miracidium Inside snail tissue Adults eggs Hermaphrodite generation mother rediae daugher rediae sporocyst cercaria

  4. Species of the genus Psilotrema, Odhner, 1913 • Psilotrema acutirostris, Oshmarin, 1963 • Psilotrema simillimum (Muhling, 1989) • Psilotrema oschmarini, Besprozvannykh, 2007 • Psilotrema breve Oshmarin, 1963 • Psilotrema castoris Orlov, 1946 • Psilotrema marki Skvorzov, 1934 • Psilotrema medioporum Oshmarin, 1963 • Psilotrema oligoon (von Linstow, 1887) • Psilotrema pharyngeatum Grabda 1954 • Psilotrema spiculigerum (Muhling, 1989) • Psilotrema tuberculatum, (de Filippi, 1857) • Psilotrema zibethicum Varenov, 1965

  5. Molecular genetic investigations, includes species of the family Psilostomatidae • Psilochasmus oxyurus - Tkach,V., Pawlowski,J. and Mariaux,J. 2000. Phylogenetic analysis of the suborder plagiorchiata (Platyhelminthes, Digenea) based on partial lsrDNA sequences // Int. J. Parasitol. 30 (1), 83-93 • Sphaeridiotrema pseudoglobulus- Moszczynska,A., Locke,S.A., Mclaughlin,J.D., Marcogliese,D.J. and Crease,T.J. Development of primers for the mitochondrial cytochrome c oxidase I gene in digenetic trematodes (Platyhelminthes) illustrates the challenge of barcoding parasitic helminths // Unpublished • Ribeiroia marini and R. ondatrae - Wilson,W.D., Johnson,P.T., Sutherland,D.R., Mone,H. and Loker,E.S. 2005.A molecular phylogenetic study of the genus Ribeiroia (Digenea): trematodes known to cause limb malformations in amphibians // J. Parasitol. 91 (5), 1040-1045.

  6. Species of the genus Psilotrema • Psilotrema acutirostris, Oshmarin, 1963 • Psilotrema simillimum (Muhling, 1989) • Psilotrema oschmarini, Besprozvannykh, 2007 • Psilotrema breve Oshmarin, 1963 • Psilotrema castoris Orlov, 1946 • Psilotrema marki Skvorzov, 1934 • Psilotrema medioporum Oshmarin, 1963 • Psilotrema oligoon (von Linstow, 1887) • Psilotrema pharyngeatum Grabda 1954 • Psilotrema spiculigerum (Muhling, 1989) • Psilotrema tuberculatum, (de Filippi, 1857) • Psilotrema zibethicum Varenov, 1965

  7. Investigated species of the genus Psilotrema(photo by V.V.Besprozvannykh) ~ 0,55 mm ~ 1,5 mm ~ 1,25 mm P. oschmarini P. acutirostris P. simillimum

  8. 28S rDNA second structure of Gydrodactulus salaris, Monogenea (from Matejusova and Cunningham, 2004) D1-D3 lenght ~ 1200-1500 bp D3 D3 D3 D3 In this study D2 and a part of D3 variable donains of 28S rRNA gene are used. D1 D1 D1 D1 D2 D2 D2 D1 D2

  9. Aim: To investigate phylogenetic relationships of the genus Psilotrema and family Psilostomatidae within order Echinostomida using partial sequence of 28S rRNA gene

  10. Tasks: • Optimizing of DNA extraction and PCR technique for trematodes; • Sequencing 28S rRNA gene fragment of three Psilotrema species; • Reconstruction of phylogenetic relationships of the genus Psilotrema and the family Psilostomatidae using current data and data from GenBank.

  11. Methods Material DNA extraction Snail • Phenol-chlorophorm extraction with Proteinase K lysis • Proteinase K lysis with following boiling with Chelex-100 • Boiling with Chelex-100 • DNA extraction with Silica • Fast DNA extraction kit, Q-Biogene isolation Cercaria encyst Adolescaria infecting Chicken PCR and DNA sequence performed with ABI GeneAmp 2700 thermal cycler and ABI 3130 genetic analyzer in the IBSS FEB RAS after 8 days Adults

  12. Families of the order Echinostomida, used in preset study (n – number of sequences) • Psilostomatidae (n=11) • Fasciolidae (n=7) • Echinostomatidae (n=5) • Phylpthalmidae (n=2) • Cyclocoeliidae (n=1)

  13. 28S rRNA gene fragment variation within Echinostomida

  14. Nucleotide composition of the 28S r RNA gene fragment of the Psilotrema species

  15. Genetic p-distances between families of Echinostomida

  16. Maximum parsimony tree of the order Echinostomida(tree topology with 50% frequency) Fasciolidae - Cyclocoeliidae Echinostomatidae Philopthalmidae Psilostomatidae Outgroup

  17. Neighbor-Joining tree (model TrN) of the order Echinostomida (tree topology with 30% frequency) Fasciolidae Echinostomatidae - Cyclocoeliidae Psilostomatidae Philopthalmidae Outgroup

  18. UPGMA tree (model TrN) of the order Echinostomida (tree topology with 20% frequency) Fasciolidae Echinostomatidae Psilostomatidae Philopthalmidae - Cyclocoeliidae Outgroup

  19. Maximum parsimony tree of the genus Psilotrema P.oschmarini P.acutirostris + P.simillimum Neighbor-Joining tree of the genus Psilotrema P.oschmarini P.acutirostris + P.simillimum

  20. Conclusions • The present study shows that given the current data, family Psilostomatidae is monophyletic and possible an ancient taxon for the order Echinostomida; • Psilotrema acutirostris and Psilotrema simillimum are likely more closely related to each other, then to P. oschmarini; Psilochasmus oxyurus is an ancient taxon relative to studied species of the genus Psilotrema; • There is no intraspecific variation of the 28S rDNA variable domains between specimens of P. oschmarini, which originated from one miracidium of previous generation; however, further studies required using other molecular markers, including mitochondrial DNA.

  21. THANKS FOR YOUR ATTENTION!

More Related