bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2020,
Номер
unknown
Опубликована: Дек. 9, 2020
ABSTRACT
Flexible
behaviors
over
long
timescales
are
thought
to
engage
recurrent
neural
networks
in
deep
brain
regions,
which
experimentally
challenging
study.
In
insects,
circuit
dynamics
a
region
called
the
central
complex
(CX)
enable
directed
locomotion,
sleep,
and
context-
experience-dependent
spatial
navigation.
We
describe
first
complete
electron-microscopy-based
connectome
of
Drosophila
CX,
including
all
its
neurons
circuits
at
synaptic
resolution.
identified
new
CX
neuron
types,
novel
sensory
motor
pathways,
network
motifs
that
likely
extract
fly’s
head-direction,
maintain
it
with
attractor
dynamics,
combine
other
sensorimotor
information
perform
vector-based
navigational
computations.
also
numerous
pathways
may
facilitate
selection
CX-driven
behavioral
patterns
by
context
internal
state.
The
provides
comprehensive
blueprint
necessary
for
detailed
understanding
underlying
flexible
navigation,
state-dependent
action
selection.
Optical
and
electron
microscopy
have
made
tremendous
inroads
toward
understanding
the
complexity
of
brain.
However,
optical
offers
insufficient
resolution
to
reveal
subcellular
details,
lacks
throughput
molecular
contrast
visualize
specific
constituents
over
millimeter-scale
or
larger
dimensions.
We
combined
expansion
lattice
light-sheet
image
nanoscale
spatial
relationships
between
proteins
across
thickness
mouse
cortex
entire
Drosophila
These
included
synaptic
at
dendritic
spines,
myelination
along
axons,
presynaptic
densities
dopaminergic
neurons
in
every
fly
brain
region.
The
technology
should
enable
statistically
rich,
large-scale
studies
neural
development,
sexual
dimorphism,
degree
stereotypy,
structural
correlations
behavior
activity,
all
with
contrast.
Flexible
behaviors
over
long
timescales
are
thought
to
engage
recurrent
neural
networks
in
deep
brain
regions,
which
experimentally
challenging
study.
In
insects,
circuit
dynamics
a
region
called
the
central
complex
(CX)
enable
directed
locomotion,
sleep,
and
context-
experience-dependent
spatial
navigation.
We
describe
first
complete
electron
microscopy-based
connectome
of
Biology,
Год журнала:
2019,
Номер
8(1), С. 13 - 13
Опубликована: Март 11, 2019
The
past
twenty
years
have
witnessed
the
most
remarkable
breakthroughs
in
our
understanding
of
molecular
and
cellular
mechanisms
that
underpin
circadian
(approximately
one
day)
time-keeping.
Across
model
organisms
diverse
taxa:
cyanobacteria
(
Our
highly
seasonal
world
restricts
insect
activity
to
brief
portions
of
the
year.
This
feature
necessitates
a
sophisticated
interpretation
changes
and
enactment
mechanisms
for
bringing
development
halt
then
reinitiating
it
when
inimical
season
is
past.
The
dormant
state
diapause
serves
bridge
unfavourable
seasons,
its
timing
provides
powerful
mechanism
synchronizing
development.
book
explores
how
signals
are
monitored
used
by
insects
enact
specific
molecular
pathways
that
generate
phenotype.
broad
perspective
offered
here
scales
from
ecological
thus
comprehensive
view
this
exciting
vibrant
research
field,
offering
insights
on
topics
ranging
pest
management,
evolution,
speciation,
climate
change
disease
transmission,
human
health,
as
well
analogies
with
other
forms
invertebrate
dormancy
mammalian
hibernation.
Many
different
functions
are
regulated
by
circadian
rhythms,
including
those
orchestrated
discrete
clock
neurons
within
animal
brains.
To
comprehensively
characterize
and
assign
cell
identity
to
the
75
pairs
of
Drosophila
neurons,
we
optimized
a
single-cell
RNA
sequencing
method
assayed
neuron
gene
expression
at
times
day.
The
data
identify
least
17
categories
with
striking
spatial
regulation
expression.
Transcription
factor
is
prominent
likely
contributes
robust
oscillation
many
transcripts,
that
encode
cell-surface
proteins
previously
shown
be
important
for
recognition
synapse
formation
during
development.
other
clock-regulated
genes
also
constitute
an
resource
future
mechanistic
functional
studies
between
and/or
temporal
signaling
circuits
elsewhere
in
fly
brain.
The
central
complex
(CX)
plays
a
key
role
in
many
higher-order
functions
of
the
insect
brain
including
navigation
and
activity
regulation.
Genetic
tools
for
manipulating
individual
cell
types,
knowledge
what
neurotransmitters
neuromodulators
they
express,
will
be
required
to
gain
mechanistic
understanding
how
these
are
implemented.
We
generated
characterized
split-GAL4
driver
lines
that
express
or
small
subsets
about
half
CX
types.
surveyed
neuropeptide
receptor
expression
using
fluorescent
situ
hybridization.
About
neuropeptides
we
examined
were
expressed
only
few
cells,
while
rest
dozens
hundreds
cells.
Neuropeptide
receptors
more
broadly
at
lower
levels.
Using
our
GAL4
drivers
mark
found
51
85
types
least
one
21
multiple
neuropeptides.
Surprisingly,
all
co-expressed
molecule
neurotransmitter.
Finally,
used
identify
whose
activation
affects
sleep,
identified
other
link
circadian
clock
CX.
well-characterized
genetic
information
on
neurotransmitter
provide
should
enhance
studies
