10.5061/DRYAD.M0CFXPP0S
Lax, Gordon
0000-0003-3986-3068
Dalhousie University
Simpson, Alastair
Dalhousie University
The molecular diversity of phagotrophic Euglenids examined using
single-cell methods
Dryad
dataset
2020
2020-10-02T00:00:00Z
2020-10-02T00:00:00Z
en
5240001725 bytes
4
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Euglenids are a diverse group of euglenozoan flagellates that includes
phototrophs, osmotrophs, andphagotrophs. Despite making up most of the
phylogenetic diversity of euglenids, phagotrophs remain understudied, and
recent work has focused on ‘deep-branching’ groups. Spirocuta is the large
clade encompassing all flexible euglenids including the phototroph and
primary osmotroph clades, plus various phagotrophs. Understanding the
phylogenetic diversity of phagotrophic spirocutes is crucial for tracing
euglenid evolution, including how phototrophs arose.We used single-cell
approaches to greatly increase sampling of SSU rDNA for phagotrophic
euglenids, particularly spirocutes, including the first sequences from
Urceolus, Jenningsia, Chasmostoma, and Sphenomonas, and expanded coverage
for Dinema and Heteronema sensu lato, amongst others. Urceolus monophyly
is unconfirmed. Organisms referred to Jenningsia form two distinct clades.
Heteronema vittatum and similar cells branch separately from Heteronema
(c.f.) globuliferum and Teloprocta/Heteronema scaphurum, while Dinema
appears as 2–3 clades. Sphenomonas is monophyletic and the deepest branch
within Petalomonadida. The census of genera markedly underestimates the
phylogenetic diversity of phagotrophs, but taxonomic restraint is
necessary when sequences are not available from type species or reasonable
surrogates. SSU rDNA phylogenies do not resolve most deep relationships
within Spirocuta, but identify units of diversity to sample in future
multigene analyses.
Manual isolation of single cells of phagotrophic euglenids, with
micrographs and video. Cells were subjected to multiple displacement
amplification (MDA) and had their SSU rRNA sequenced. Resulting SSU rRNA
sequences were used to reconstruct a comprehensive molecular phylogeny of
euglenids.
Raw image files are in jpeg or TIFF formats, videos are in mp4-format
(H.264 codec), alignment files are in fasta-format, and treefiles are in
NEWICK-format.