Looking for new markers to elucidate Sponge Phylogeny

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Looking for new markers to elucidate Sponge
Phylogeny
Naama Gil Advisor Dr. Dorothee Huchon
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Phylogeny
The study of evolutionary relatedness among
various organisms
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Vertebrata
Arthropoda
Bilateria
Nematoda
Metazoa
Annelida
Ctenophora
Cnidaria
Porifera
Placozoa
Choanoflagellata
Fungi
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• SpongePorifera
• From Latin bearing pores
• Sessile aquatic animals, mostly
• marines, but some live in fresh water
• Mostly filter feeders
• Does not have complex systems
• Reproduce sexually and a-sexually

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• The Sponge body is a two layered one, different
  groups have different body plans

Asconoid
Syconoid
Leuconoid
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• Have several type of skeleton Spongin, silica
  or calcium carbonate.

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????? ???????? Phylum Porifera

• Three main classes
• Calcarea

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????? ???????? Phylum Porifera

• Three main classes
• Hexactinellida

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????? ???????? Phylum Porifera

Three main classes Demospongiae
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Classical phylogeny
Eumetazoa
Calcarea
Demospongiae
Hexactinellida
Choanoflagellata
Fungi
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Molecular phylogeny
Eumetazoa
Calcarea
Demospongiae
Hexactinellida
Choanoflagellata
Fungi
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Various molecular markers have been used to try
and solve sponge phylogeny
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18s rDNA
Fungi
Choanoflagellata
Hexactinellida
Demospongiae
Calcarea
Sponge paraphyly and the origin of Metazoa C.
BORCHIELLINI, M. MANUEL, E. ALIVON, N.
BOURY-ESNAULT, J. VACELET Y. LE PARCO
Eumetazoa
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ALD, ATPB, CAT, EF1a, MAT, PFK, TPI
Poriferan paraphyly and its implications for
Precambrian palaeobiology E. A. SPERLING, D.
PISANI K. J. PETERSON
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Concatenated Analysis Sheds Light on
Early Metazoan Evolution and Fuels a
Modern Urmetazoon Hypothesis Bernd
Schierwater , Michael Eitel, Wolfgang Jakob,
Hans-Jurgen Osigus, Heike Hadrys, Stephen L.
Dellaporta, Sergios-Orestis Kolokotronis, Rob
DeSalle
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THE RESERCH GOAL
Finding more DNA markers for solving sponge
phylogeny
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Methods
First choose a gene Second design
primers Third use PCR for gene
amplification Forth sequence the gene Fifth
build a tree
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First choose a gene to work on
The exons must be long enough, introns are too
variable to be used as molecular markers
Nematostella
Homo sapiens
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First choose a gene to work on
The exons must be long enough, introns are to
variable to be used as molecular markers
The exons must be long enough, introns are too
variable to be used as molecular markers
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First choose a gene to work on
The gene have to be conserved enough to allow
primer design according to related species and
variable enough to enable phylogenetic analysis
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Second design primers according to closely
related species
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Third use PCR for gene amplification
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Forth sequence the gene
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Fifth build a tree
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Preliminary results with Sulfite Oxidase
Arabidopsis
Danio
Chondrosia
Amphimedon
Calcarea
Clathrina
Ciona
Tribolium
Branchiostoma
Xenopus
Homo
Equus
0.2
Calcarea
Demospongiae
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• Next steps
• Continue to sequence the Sulfite Oxidase gene
  from more species
• Find additional suitable markers
• Compare with phylogenies reconstructed from other
  markers

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Thank you!