Centrohelida is still searching for aphylogenetic home-analyses of seven Raphidiophrys contractilis genes-Inst. Biol. Sci., Univ. Tsukuba
Miako Sakaguchi

Phylogeny of eukaryotes？
Raphidiophrys contractilis

Classification of Heliozoa？

Aim of this study→ To clarify the phylogenetic position of→ Centrohelida…

ML combined analyses of Centrohelida
 7-gene data sets
(SSU rRNA, actin, α-tubulin, β-tubulin,EF2, HSP70, HSP90）
 ‘concatenate model’ & ‘separate model’Multi-gene ML analysis –concatenate model6-protein： α-tubulin, β-tubulin, actin, EF2, HSP70, HSP90

proml
2937aa sites

Multi-gene ML analyses –separate model7-gene
α-tubulin, β-tubulin, Actin, EF2
HSP70, HSP90, SSU rRNA

Centrohelida branched with…
→ 、Rhodophyta→ 、Viridiplantae→ 、Stramenopiles/Alveolata

But, the RELL BP support forthis clade was weakGene-specific signals –α-tubulin5-geneΔTba

5-geneΔTbb
ΔAct

Gene-specific signals –α-tubulin5-gene
Δ70
Δ90

5-geneΔEF2

Gene-specific signals –α-tubulin5-geneΔTba

Multi-gene analyses…
→ including α-tubulin
The Dip/Par union formed a cladewith the Opisthokonta with high
RELL BP support→ excluding α-tubulin
The Dip/Par union did not clusterwith the Opisthokonta

The affinity between the Dip/Parunion and the Opisthokonta isattributed solely to the α-tubulin
signalGene-specific signals –EF27-gene

Multi-gene analyses…
→ including EF2
Rhodophyta and Viridiplantae
formed a monophyletic clade(Plantae) with high RELL BPsupport
The robust clade is attributed
to the EF2 signal…?

Gene-specific signals –EF26-geneΔEF25-geneΔEF2254

Gene-specific signals –EF25-geneΔEF2

Multi-gene analyses…
→ including EF2
The Rhodophyta formed a cladewith the Viridiplantae with high
RELL BP support→ excluding EF2
The Rhodophyta did not clusterwith the Viridiplantae
4

Other genes do not support
the monophyly…?

Gene-specific signals –EF223-geneΔEF2

Multi-gene analyses…
→ excluding EF2
Rhodophyta formed a clade withViridiplantae
Other genes support themonophyly of the Rhodophyta
and Viridiplantae
Burger et al. (1999)
Rodríguez-Ezpeleta et al. (2005)

The phylogenetic signals in ourdata sets without EF2 are
insufficient…

AU test

0.01 ≤ P < 0.05

4-geneΔEF25-gene

ΔTba

5-geneΔSSU

P ≥ 0.05

6-gene7-genebest

P < 0.01

Conclusion
 Multi-gene combined analyses of Centrohelida→concatenate model (ΔSSU rRNA)→separate model→AU test
the phylogenetic position of Centrohelida isunclear
 single-gene jackknifing
strong gene-specific signals are predominant in
our multi-gene data

Larger scale multi-gene phylogenies are necessary toclarify the origin and evolution of Centrohelida

Gene-specific signals –SSU rRNA7-gene

6-geneΔSSU

Excavata

Gene-specific signals –SSU rRNA6-geneΔTba
ΔTbb
ΔActΔ70Δ906-geneΔEF2

Gene-specific signals –SSU rRNA6-geneΔSSU

Multi-gene analyses…
→ including SSU rRNA
The Dip/Par union formed a cladewith the Eug/Het union→ excluding SSU rRNA
The Dip/Par union did not clusterwith the Eug/Het union

The Excavata clade issupported only by SSU rRNA

Gene-specific signals –α-tubulin6-geneΔSSU

Multi-gene analyses…
→ excluding SSU rRNA
The Dip/Par union did not clusterwith the Eug/Het union, butbranched with the Opisthokonta
The Dip/Par union has a sister
relationship with theOpisthokonta...?