bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 21, 2024
Abstract
Complex
eukaryotes
generally
experience
some
degree
of
ecological
transition
as
they
develop,
which
is
usually
accompanied
by
the
expression
different
traits
across
their
ontogeny.
Theory
suggests
evolution
differentiation
between
life
stages
facilitated
genes
at
points
throughout
ontogeny,
alleviates
pleiotropic
evolutionary
constraints.
Therefore,
ascertaining
what
contributes
to
specialized
patterns
gene
ontogeny
fundamental
understanding
ontogenetic
complexity.
Expression
divergence
duplicate
and
organization
on
chromosomes
have
been
identified
important
features
relatively
complex
ontogenies.
one
could
predict
that
link
transcriptional
specialization
may
be
weaker
in
simpler
cycles.
Here,
we
investigated
links
duplication,
organization,
stage-specific
simple
Caenorhabditis
elegans
cycle.
We
found
signatures
stage-biased
chromosomal
regions
were
C.
than
has
previously
described
organisms
with
more
Furthermore,
extent
varied
pattern
was
constrained
.
Overall,
our
findings
add
a
body
evidence
duplication
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 24, 2025
Gene
regulatory
networks
(GRNs)
integrate
genetic
and
environmental
signals
to
coordinate
complex
phenotypes
evolve
through
a
balance
of
selection
drift.
Using
publicly
available
datasets
from
Caenorhabditis
elegans
,
we
investigated
the
extent
natural
on
transcript
abundance
by
linking
population-scale
variation
in
gene
expression
fecundity,
key
fitness
component.
While
most
genes
covaried
only
weakly
with
fitness,
which
is
typical
for
polygenic
traits,
identified
seven
transcripts
under
significant
directional
selection.
These
included
nhr-114
feh-1,
implicating
nutrient-sensing
metabolic
pathways
as
impacting
fitness.
Stronger
tissue-specific
older
highlighted
germline
nervous
system
focal
points
adaptive
change.
Network
position
further
constrained
expression;
high-connectivity
faced
stronger
stabilizing
selection,
highlighting
GRN
architecture
factor
microevolutionary
dynamics.
The
activity
transcription
factors
such
zip-3
regulates
mitochondrial
stress
responses,
emerged
targets
revealing
potential
links
between
energy
homeostasis
Our
findings
demonstrate
how
GRNs
mediate
interplay
drift,
shaping
trajectories
phenotypic
diversity.
Neural
network
architecture
determines
its
functional
output.
However,
the
detailed
mechanisms
are
not
well
characterized.
In
this
study,
we
focused
on
neural
architectures
of
male
and
hermaphrodite
C.
elegans
association
with
sexually
dimorphic
behaviors.
We
applied
graph
theory
computational
neuroscience
methods
to
systematically
discern
features
these
two
networks.
Our
findings
revealed
that
a
small
percentage
sexual-specific
neurons
exerted
dominance
throughout
entire
net-work,
suggesting
male’s
prioritized
sexual-related
behavior
outputs.
Based
structural
dynamical
characteristics
complete
networks,
sub-networks
containing
sex-specific
their
immediate
neighbors,
or
exclusively
comprising
sex-shared
neurons,
predicted
behavioral
outcomes
for
males
hermaphrodites.
To
verify
prediction,
performed
calcium
imaging
experiments
dissected
circuit
is
specific
increased
spontaneous
local
search
in
mate-searching.
research
sheds
light
circuits
underlie
behaviors
elegans,
provides
significant
insights
into
inter-connected
relationship
between
at
whole-brain
level.
Neural
network
architecture
determines
its
functional
output.
However,
the
detailed
mechanisms
are
not
well
characterized.
In
this
study,
we
focused
on
neural
architectures
of
male
and
hermaphrodite
C.
elegans
association
with
sexually
dimorphic
behaviors.
We
applied
graph
theory
computational
neuroscience
methods
to
systematically
discern
features
these
two
networks.
Our
findings
revealed
that
a
small
percentage
sexual-specific
neurons
exerted
dominance
throughout
entire
net-work,
suggesting
male’s
prioritized
sexual-related
behavior
outputs.
Based
structural
dynamical
characteristics
complete
networks,
sub-networks
containing
sex-specific
their
immediate
neighbors,
or
exclusively
comprising
sex-shared
neurons,
predicted
behavioral
outcomes
for
males
hermaphrodites.
To
verify
prediction,
performed
calcium
imaging
experiments
dissected
circuit
is
specific
increased
spontaneous
local
search
in
mate-searching.
research
sheds
light
circuits
underlie
behaviors
elegans,
provides
significant
insights
into
inter-connected
relationship
between
at
whole-brain
level.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 29, 2025
Abstract
Understanding
how
genomic
information
is
selectively
utilized
across
different
life
stages
essential
for
deciphering
the
developmental
and
evolutionary
strategies
of
metazoans.
In
holometabolous
insects,
dynamic
expression
genes
enables
distinct
functional
adaptations
at
embryonic,
larval,
pupal
adult
stages,
likely
contributing
to
their
success.
While
Drosophila
melanogaster
has
been
extensively
studied,
less
known
about
dynamics
that
could
govern
stage-specific
gene
expression.
To
address
this
question,
we
compared
distribution
genes,
i.e.,
expressed
in
temporally
restricted
development
D.melanogaster
Aedes
aegypti
.
Using
tau-scoring,
a
computational
method
determine
specificity,
found
that,
on
average,
large
proportion
(20
30%
all
protein-coding
genes)
both
species
exhibit
specific
stages.
Phylostratigraphy
analysis,
date
age
further
revealed
fall
into
two
major
categories:
highly
conserved
recently
evolved.
Notably,
many
evolved
identified
A.aegypti
are
Diptera
order
35%
genes),
highlighting
ongoing
processes
continue
shape
life-stage
transitions.
Overall,
our
findings
underscore
complex
interplay
between
age,
morphological
transformations
development.
These
results
suggest
attraction
critical
stage
transitions
an
process
may
not
be
constant
time
or
uniform
lineages,
offering
new
insights
adaptability
diversification
dipteran
genomes.
Research
Highlights
Metazoan
genomes
contain
instructions
single
cell
develop
complete
organism.
We
investigated
i.e.
only
during
certain
species.
20
active
have
emerged
recently,
suggesting
shaping
One
avenue
to
better
understand
brain
evolution
is
map
molecular
patterns
of
evolutionary
changes
in
neuronal
cell
types
across
entire
nervous
systems
distantly
related
species.
Generating
whole-animal
single-cell
transcriptomes
three
nematode
species
from
the
Caenorhabditis
genus,
we
observed
a
remarkable
stability
neuronal-cell-type
identities
over
more
than
45
million
years
evolution.
Conserved
combinatorial
expression
homeodomain
transcription
factors
are
among
best
classifiers
homologous
neuron
classes.
Unexpectedly,
discover
an
extensive
divergence
signaling
pathways.
Although
neurotransmitter-producing
neurons
(glutamate,
acetylcholine,
γ-aminobutyric
acid
[GABA],
and
several
monoamines)
remain
stable,
ionotropic
metabotropic
receptors
for
all
these
neurotransmitter
shows
substantial
divergence,
resulting
half
classes
changing
their
capacity
be
receptive
specific
neurotransmitters.
Neuropeptidergic
also
remarkably
divergent,
both
at
level
neuropeptide
receptor
expression,
yet
overall
dense
network
topology
wireless
neuropeptidergic
connectome
remains
stable.
Novel
pathways
suggested
by
our
discovery
small
secreted
proteins
that
show
no
obvious
hallmarks
conventional
neuropeptides
but
similar
highly
neuron-type-specific
evolvable
profiles.
In
conclusion,
investigating
resolution
single-neuron
classes,
uncover
may
reflect
basic
principles
governing
novelty
circuits.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 25, 2024
One
avenue
to
better
understand
brain
evolution
is
map
molecular
patterns
of
evolutionary
changes
in
neuronal
cell
types
across
entire
nervous
systems
distantly
related
species.
Generating
whole-animal
single-cell
transcriptomes
three
nematode
species
from
the
