Abstract
The
formation
of
the
vertebrate
body
involves
coordinated
production
trunk
tissues
from
progenitors
located
in
posterior
embryo.
Although
vitro
models
using
pluripotent
stem
cells
replicate
aspects
this
process
1–10
,
they
lack
crucial
components,
most
notably
notochord—a
defining
feature
chordates
that
patterns
surrounding
11
.
Consequently,
cell
types
dependent
on
notochord
signals
are
absent
current
human
formation.
Here
we
performed
single-cell
transcriptomic
analysis
chick
embryos
to
map
molecularly
distinct
progenitor
populations
and
their
spatial
organization.
Guided
by
map,
investigated
how
differentiating
develop
a
stereotypical
organization
types.
We
found
YAP
inactivation
conjunction
with
FGF-mediated
MAPK
signalling
facilitated
WNT
pathway
activation
induced
expression
TBXT
(also
known
as
BRA).
In
addition,
timely
inhibition
WNT-induced
NODAL
BMP
regulated
proportions
different
tissue
types,
including
notochordal
cells.
This
enabled
us
create
three-dimensional
model
development
undergoes
morphogenetic
movements,
producing
elongated
structures
ventral
neural
mesodermal
tissues.
Our
findings
provide
insights
into
mechanisms
underlying
establish
more
comprehensive
development.
paves
way
for
future
studies
patterning
physiologically
relevant
environment.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Март 7, 2023
ABSTRACT
Elucidating
the
developmental
processes
of
organisms
requires
a
comprehensive
understanding
cellular
lineages
in
spatial,
temporal,
and
molecular
domains.
In
this
study,
we
introduce
Zebrahub,
dynamic
atlas
zebrafish
embryonic
development
that
integrates
single-cell
sequencing
time
course
data
with
lineage
reconstructions
facilitated
by
light-sheet
microscopy.
This
offers
high-resolution
in-depth
insights
into
development,
achieved
through
individual
embryos
across
ten
stages,
complemented
trajectory
reconstructions.
Zebrahub
also
incorporates
an
interactive
tool
to
navigate
complex
flows
derived
from
microscopy
data,
enabling
silico
fate
mapping
experiments.
To
demonstrate
versatility
our
multi-modal
resource,
utilize
provide
fresh
pluripotency
Neuro-Mesodermal
Progenitors
(NMPs).
Our
publicly
accessible
web-based
platform,
is
foundational
resource
for
studying
at
both
transcriptional
spatiotemporal
levels,
providing
researchers
integrated
approach
exploring
analyzing
complexities
during
embryogenesis.
Cell Systems,
Год журнала:
2021,
Номер
13(1), С. 12 - 28.e3
Опубликована: Сен. 17, 2021
Fate
decisions
in
developing
tissues
involve
cells
transitioning
between
discrete
cell
states,
each
defined
by
distinct
gene
expression
profiles.
The
Waddington
landscape,
which
the
development
of
a
is
viewed
as
ball
rolling
through
valley
filled
terrain,
an
appealing
way
to
describe
differentiation.
To
construct
and
validate
accurate
landscapes,
quantitative
methods
based
on
experimental
data
are
necessary.
We
combined
principled
statistical
with
framework
catastrophe
theory
approximate
Bayesian
computation
formulate
dynamical
landscape
that
accurately
predicts
fate
outcomes
pluripotent
stem
exposed
different
combinations
signaling
factors.
Analysis
revealed
two
ways
make
binary
choice
one
fates.
suggest
these
represent
archetypal
designs
for
developmental
decisions.
approach
broadly
applicable
analysis
differentiation
determining
logic
Axial
elongation
of
the
neural
tube
is
crucial
during
mammalian
embryogenesis
for
anterior-posterior
body
axis
establishment
and
subsequent
spinal
cord
development,
but
these
processes
cannot
be
interrogated
directly
in
humans
as
they
occur
post-implantation.
Here,
we
report
an
organoid
model
extension
derived
from
human
pluripotent
stem
cell
(hPSC)
aggregates
that
have
been
caudalized
with
Wnt
agonism,
enabling
them
to
recapitulate
aspects
morphological
temporal
gene
expression
patterns
development.
Elongating
organoids
consist
largely
neuroepithelial
compartments
contain
TBXT+SOX2+
neuro-mesodermal
progenitors
addition
PAX6+NES+
progenitors.
A
critical
threshold
agonism
stimulated
singular
axial
extensions
while
maintaining
multiple
lineages,
such
displayed
regionalized
anterior-to-posterior
HOX
hindbrain
(HOXB1)
regions
spatially
distinct
brachial
(HOXC6)
thoracic
(HOXB9)
regions.
CRISPR
interference-mediated
silencing
TBXT,
a
pathway
target,
increased
compartmentalization,
abrogated
disrupted
uniaxial
elongation.
Together,
results
demonstrate
potent
capacity
hPSC
undergo
manner
can
used
dissect
cellular
organization
patterning
decisions
dictate
early
nervous
system
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Фев. 28, 2023
Abstract
The
formation
of
the
vertebrate
body
involves
coordinated
and
progressive
production
trunk
tissues
from
progenitors
located
in
posterior
embryo.
In
vitro
models
based
on
pluripotent
stem
cells
(PSCs)
replicate
aspects
this
process,
but
they
lack
some
tissue
components
normally
present
trunk.
Most
strikingly,
notochord,
a
hallmark
chordates
source
midline
signals
that
pattern
surrounding
tissues,
is
absent
current
human
formation.
To
investigate
how
formed,
we
performed
single-cell
transcriptomic
analysis
chick
embryos.
This
delineated
molecularly
discrete
progenitor
populations,
which
spatially
locate
embryo,
compare
across
species,
relate
to
signalling
activity.
Guided
by
map,
determined
differentiating
PSCs
develop
stereotypical
spatial
organization
types.
We
found
LATS1/2
repression
YAP
activity,
conjunction
with
FGF-mediated
MAPK
activation,
induced
transcription
factor
Bra/TBXT
facilitated
WNT
signaling.
addition,
inhibiting
WNT-induced
NODAL
BMP
signaling
cascade
at
appropriate
time
regulated
proportions
different
types
produced,
including
notochordal
cells.
used
information
create
an
integrated
3D
model
gastrulation
undergoing
morphogenetic
movements
produce
elongated
structures
notochord
patterned
neural
Together
data
provide
insight
into
mechanisms
responsible
for
comprise
pave
way
future
studies
patterning
tissue-like
environment.
The
generation
of
the
post-cranial
embryonic
body
relies
on
coordinated
production
spinal
cord
neurectoderm
and
presomitic
mesoderm
cells
from
neuromesodermal
progenitors
(NMPs).
This
process
is
orchestrated
by
pro-neural
pro-mesodermal
transcription
factors
that
are
co-expressed
in
NMPs
together
with
Hox
genes,
which
critical
for
axial
allocation
NMP
derivatives.
reside
a
posterior
growth
region,
marked
expression
Wnt,
FGF
Notch
signalling
components.
While
importance
Wnt
influencing
induction
differentiation
well
established,
precise
role
remains
unclear.
Here,
we
show
Wnt/FGF-driven
human
stem
(hESCs)
signalling.
Using
hESC-derived
chick
embryo
grafting,
demonstrate
directs
character
at
expense
neural
fate.
We
also
contributes
to
activation
HOX
gene
NMPs,
partly
non-cell-autonomous
manner.
Finally,
provide
evidence
exerts
its
effects
via
establishment
negative
feedback
loop
