bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Sept. 22, 2024
Abstract
Placozoa
are
millimeter-sized,
flat,
irregularly
shaped
ciliated
animals
that
crawl
on
surfaces
in
warm
oceans
feeding
biofilms,
which
they
digest
externally.
They
stand
out
from
other
due
to
their
simple
body
plans.
lack
organs,
cavities,
muscles
and
a
nervous
system
have
only
seven
broadly
defined
morphological
cell
types,
each
with
unique
distribution.
Analyses
of
single
transcriptomes
four
species
placozoans
revealed
greater
diversity
secretory
types
than
evident
studies,
but
the
locations
many
these
new
were
unknown
it
was
unclear
represent.
Furthermore,
there
contradictions
between
conclusions
previous
studies
RNAseq
studies.
To
address
issues,
we
used
mRNA
probes
for
genes
encoding
products
expressed
different
metacells
Trichoplax
adhaerens
localize
cells
whole
mounts
dissociated
cultures,
where
features
could
be
visualized
identified.
The
nature
functions
granules
further
investigated
electron
microscopic
techniques
by
imaging
secretion
live
during
episodes.
We
found
two
participate
disintegrating
prey,
one
resembling
lytic
type
mammals
another
combining
zymogen
gland
enterocytes.
identified
epithelial
expressing
glycoproteins
or
short
peptides
implicated
defense.
located
peptidergic
mucocytes.
Our
findings
reveal
mechanisms
use
feed
protect
themselves
pathogens
clues
about
neuropeptidergic
signaling.
compare
placozoan
animal
phyla
gain
insight
general
evolutionary
trends
diversification,
as
well
pathways
leading
emergence
synapomorphies.
Frontiers in Cell and Developmental Biology,
Journal Year:
2022,
Volume and Issue:
10
Published: Dec. 23, 2022
How
to
make
a
neuron,
synapse,
and
neural
circuit?
Is
there
only
one
'design'
for
architecture
with
universally
shared
genomic
blueprint
across
species?
The
brief
answer
is
"No."
Four
early
divergent
lineages
from
the
nerveless
common
ancestor
of
all
animals
independently
evolved
distinct
neuroid-type
integrative
systems.
One
these
subset
nets
in
comb
jellies
unique
synapses;
second
lineage
well-known
Cnidaria
+
Bilateria;
two
others
are
non-synaptic
neuroid
systems
sponges
placozoans.
By
integrating
scRNA-seq
microscopy
data,
we
revise
definition
neurons
as
synaptically-coupled
polarized
highly
heterogenous
secretory
cells
at
top
behavioral
hierarchies
learning
capabilities.
This
physiological
(not
phylogenetic)
separates
'true'
non-synaptically
gap
junction-coupled
executing
more
stereotyped
behaviors.
Growing
evidence
supports
hypothesis
multiple
origins
synapses.
Thus,
many
non-bilaterian
bilaterian
neuronal
classes,
circuits
or
considered
functional
rather
than
genetic
categories,
composed
non-homologous
cell
types.
In
summary,
little-explored
examples
convergent
evolution
representatives
branching
metazoans
provide
conceptually
novel
microanatomical
architectures
controls
prospects
neuro-engineering
synthetic
biology.
PeerJ,
Journal Year:
2024,
Volume and Issue:
12, P. e16970 - e16970
Published: Feb. 23, 2024
Coral
reefs
are
biodiverse
ecosystems
that
rely
on
trophodynamic
transfers
from
primary
producers
to
consumers
through
the
detrital
pathway.
The
sponge
loop
hypothesis
proposes
sponges
consume
dissolved
organic
carbon
(DOC)
and
produce
large
quantities
of
detritus
coral
reefs,
with
this
turn-over
approaching
daily
gross
production
reef
ecosystem.
In
study,
we
collected
samples
in
epilithic
algal
matrix
(EAM)
potential
sources
over
two
seasons
forereef
at
Carrie
Bow
Cay,
Belize.
We
chose
location
maximize
likelihood
finding
support
for
because
Caribbean
have
higher
abundances
than
other
tropical
worldwide
Mesoamerican
barrier
is
an
archetypal
used
stable
isotope
analyses
eDNA
metabarcoding
determine
composition
detritus.
determined
EAM
was
derived
a
variety
benthic
pelagic
sources,
(micro-
macroalgae)
as
major
contributors
metazoans
(Arthropoda,
Porifera,
Cnidaria,
Mollusca)
minor
contributors.
None
species
reportedly
were
present
cnidarian
signature
dominated
by
octocorals,
scarcity
hard
corals.
also
varied
seasonally.
negligible
contribution
contrasts
pathway
originally
proposed
hypothesis.
findings
indicate
mix
calmer
summer
primarily
more
turbulent
spring.
Journal of Experimental Biology,
Journal Year:
2025,
Volume and Issue:
228(3)
Published: Feb. 1, 2025
ABSTRACT
Sponges
(phylum
Porifera)
are
an
early
diverging
animal
lineage
without
nervous
and
muscular
systems,
yet
they
able
to
produce
coordinated
whole-body
contractions
in
response
disturbances.
Little
is
known
about
the
underlying
signalling
mechanisms
coordinating
such
responses.
Previous
studies
demonstrated
that
sponges
respond
specifically
chemicals
as
l-glutamate
γ-amino-butyric
acid
(GABA),
which
trigger
prevent
contractions,
respectively.
Genes
for
purinergic
P2X-like
receptors
present
several
sponge
genomes,
leading
us
ask
whether
ATP
works
with
glutamate
coordinate
it
does
other
systems.
Using
pharmacological
approaches
on
freshwater
Ephydatia
muelleri,
we
show
involved
contractions.
Bath
application
of
caused
a
rapid,
sustained
expansion
excurrent
canals
dose-dependent
manner.
Complete
occurred
when
was
added
presence
apyrase,
enzyme
hydrolyses
ATP.
Application
ADP,
first
metabolic
product
hydrolysis,
triggered
complete
whereas
AMP,
subsequent
metabolite,
did
not
response.
Blocking
from
binding
activating
P2X
pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic
(PPADS)
prevented
both
glutamate-
ATP-triggered
suggesting
downstream
glutamate.
Bioinformatic
analysis
revealed
two
receptor
sequences,
one
groups
vertebrate
receptors.
Altogether,
our
results
confirm
by
sponge.
EvoDevo,
Journal Year:
2025,
Volume and Issue:
16(1)
Published: Feb. 14, 2025
How
animal
cell
types,
tissues,
and
regional
body
plans
arose
is
a
fundamental
question
in
EvoDevo.
Many
current
efforts
attempt
to
link
genetic
information
the
morphology
of
cells,
tissues
regionalization
using
single-cell
sequencing
populations.
However,
lack
in-depth
understanding
non-bilaterian
animals
remains
considerable
block
transitions
between
bilaterian
cells
tissues.
Sponges
(Porifera),
one
earliest
diverging
phyla,
pose
particular
challenge
this
endeavour,
because
their
mouths,
gut,
conventional
muscle
nervous
systems.
With
goal
help
bridge
gap,
we
have
studied
morphology,
behaviour
transcriptomics
tissue
types
an
easily
accessible
well-studied
species
freshwater
sponge,
Ephydatia
muelleri.
New
features
described
here
include:
polarized
external
epithelium,
new
contractile
sieve
that
forms
entry
incurrent
canals,
motile
cilia
on
apopyle
at
exit
choanocyte
chambers,
non-motile
excurrent
canals
oscula.
Imaging
vivo
shows
distinct
behavioural
characteristics
mesohyl.
Transcriptomic
phenotypes
three
(cystencytes,
choanocytes
archaeocytes)
captured
live
indicate
cell-type
transcriptomes
are
distinct.
Importantly,
individual
archaeocytes
show
range
transcriptomic
which
supported
by
expression
different
genes
subsets
type.
In
contrast,
all
five
sampled
revealed
highly
uniform
with
significantly
fewer
expressed
than
other
types.
Our
study
sponges
whose
diversity
both
functionally
complex,
but
together
enable
like
metazoans,
sense
respond
stimuli.
PLoS ONE,
Journal Year:
2025,
Volume and Issue:
20(4), P. e0311271 - e0311271
Published: April 22, 2025
Placozoa
are
millimeter-sized,
flat,
irregularly
shaped
ciliated
animals
that
crawl
on
surfaces
in
warm
oceans
feeding
biofilms,
which
they
digest
externally.
They
stand
out
from
other
due
to
their
simple
body
plans.
lack
organs,
cavities,
muscles
and
a
nervous
system
have
only
seven
broadly
defined
morphological
cell
types,
each
with
unique
distribution.
Analyses
of
single
transcriptomes
four
species
placozoans
revealed
greater
diversity
secretory
types
than
evident
studies,
but
the
locations
many
these
new
were
unknown
it
was
unclear
represent.
Furthermore,
there
contradictions
between
conclusions
previous
studies
RNAseq
studies.
To
address
issues,
we
used
mRNA
probes
for
genes
encoding
products
expressed
different
metacells
Trichoplax
adhaerens
localize
cells
whole
mounts
dissociated
cultures,
where
features
could
be
visualized
identified.
The
nature
functions
granules
further
investigated
electron
microscopic
techniques
by
imaging
secretion
live
during
episodes.
We
found
two
participate
disintegrating
prey,
one
resembling
lytic
type
mammals
another
combining
zymogen
gland
enterocytes.
identified
epithelial
expressing
glycoproteins
or
short
peptides
implicated
defense.
located
peptidergic
mucocytes.
Our
findings
reveal
mechanisms
use
feed
protect
themselves
pathogens
clues
about
neuropeptidergic
signaling.
compare
placozoan
animal
phyla
gain
insight
general
evolutionary
trends
diversification,
as
well
pathways
leading
emergence
synapomorphies.
Biological Theory,
Journal Year:
2024,
Volume and Issue:
unknown
Published: June 13, 2024
Abstract
Eating
is
a
fundamental
behavior
in
which
all
organisms
must
engage
order
to
procure
the
material
and
energy
from
their
environment
that
they
need
maintain
themselves.
Since
controlling
eating
requires
procuring,
processing,
assessing
information,
it
constitutes
cognitive
activity
provides
productive
domain
for
pursuing
biology
as
proposed
by
Ladislav
Kováč.
In
agreement
with
Kováč,
we
argue
cognition
fundamentally
grounded
chemical
signaling
processing.
To
support
this
thesis,
adopt
Cisek’s
strategy
of
phylogenetic
refinement,
focusing
on
two
animal
phyla,
Porifera
Placozoa,
do
not
have
neurons,
muscles,
or
an
alimentary
canal,
but
nonetheless
coordinate
cells
multiple
types
eat.
We
review
what
research
has
revealed
so
far
about
how
these
animals
gather
process
information
control
behavior.
Coral Reefs,
Journal Year:
2023,
Volume and Issue:
42(2), P. 367 - 381
Published: Jan. 24, 2023
Abstract
Coral
reefs
in
the
northern
Red
Sea
experience
strong
seasonality.
This
affects
reef
carbon
(C)
cycling,
but
ecosystem-wide
quantification
of
C
fluxes
such
is
limited.
study
quantified
seasonal
community
with
incubations.
Resulting
data
were
then
incorporated
into
linear
inverse
models
(LIM).
For
spring,
additional
sponge
incubation
results
allowed
for
unique
assessment
contribution
sponges
to
cycling.
The
coral
ecosystem
was
heterotrophic
throughout
all
seasons
as
gross
primary
production
(GPP;
136–200,
range
means
mmol
m
−2
d
−1
)
less
than
respiration
(R;
192–279),
and
balanced
by
import
organic
(52–100),
88‒92%
which
being
dissolved
(DOC).
Hard
GPP
(74–110)
R
(100–137),
well
pelagic
bacteria
DOC
uptake
(58–101)
(42–86),
largest
across
seasons.
least
spring
(highest
irradiance)
(GPP:R
0.81),
most
summer
fall
higher
water
temperatures
(0.68
0.60,
respectively).
Adding
model
increased
(247
±
8
without
353
13
(mean
SD)).
Sponges
this
demand
primarily
(105
6,
97%
cryptic
sponges).
rate
comparable
(104
5)
placing
among
dominant
cycling
groups
reef.