bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 17, 2024
Abstract
Genetically
encoded
calcium
(Ca
2+
)
indicators
(GECIs)
are
widely
used
for
imaging
neuronal
activity,
yet
current
limitations
of
existing
red
fluorescent
GECIs
have
constrained
their
applicability.
The
inherently
dim
fluorescence
and
low
signal-to-noise
ratio
red-shifted
posed
significant
challenges.
More
critically,
several
red-fluorescent
exhibit
photoswitching
when
exposed
to
blue
light,
thereby
limiting
applicability
in
all-optical
experimental
approaches.
Here,
we
present
the
development
PinkyCaMP,
first
mScarlet-based
Ca
sensor
that
outperforms
sensors
brightness,
photostability,
ratio,
compatibility
with
optogenetics
neurotransmitter
imaging.
PinkyCaMP
is
well-tolerated
by
neurons,
showing
no
toxicity
or
aggregation,
both
vitro
vivo
.
All
approaches,
including
single-photon
excitation
methods
such
as
fiber
photometry,
widefield
imaging,
miniscope
well
two-photon
awake
mice,
fully
compatible
PinkyCaMP.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: July 4, 2023
Abstract
The
ability
to
distinguish
a
threatening
from
non-threatening
conspecific
based
on
past
experience
is
critical
for
adaptive
social
behaviors.
Although
recent
progress
has
been
made
in
identifying
the
neural
circuits
that
contribute
different
types
of
positive
and
negative
interactions,
mechanisms
enable
discrimination
individuals
aversive
experiences
remain
unknown.
Here,
we
developed
modified
fear
conditioning
paradigm
induced
both
sexes
robust
behavioral
associated
with
footshock
(CS+)
non-reinforced
interaction
partner
(CS-).
Strikingly,
chemogenetic
or
optogenetic
silencing
hippocampal
CA2
pyramidal
neurons,
which
have
previously
implicated
novelty
recognition
memory,
resulted
generalized
avoidance
behavior
towards
equally
familiar
CS-and
CS+.
One-photon
calcium
imaging
revealed
accuracy
representations
discriminate
CS+
CS-animal
was
enhanced
following
strongly
correlated
discrimination.
Moreover
incorporated
abstract
representation
valence
irrespective
identity
location.
Thus,
our
results
demonstrate,
first
time,
same
subregion
mediates
memories
familiarity
threat,
through
incorporation
into
an
initial
identity.
Hippocampus,
Journal Year:
2024,
Volume and Issue:
34(9), P. 464 - 490
Published: July 1, 2024
Olfactory
oscillations
may
enhance
cognitive
processing
through
coupling
with
beta
(β,
15-30
Hz)
and
gamma
(γ,
30-160
activity
in
the
hippocampus
(HPC).
We
hypothesize
that
between
olfactory
bulb
(OB)
HPC
is
increased
by
cholinergic
activation
control
rats
reduced
kainic-acid-treated
epileptic
rats,
a
model
of
temporal
lobe
epilepsy.
OB
γ2
(63-100
power
was
higher
during
walking
immobility-awake
(IMM)
compared
to
sleep,
while
γ1
(30-57
grooming
than
other
behavioral
states.
Muscarinic
agonist
pilocarpine
(25
mg/kg
ip)
peripheral
muscarinic
blockade
OB-HPC
coherence
at
β
frequency
bands.
A
similar
effect
found
after
physostigmine
(0.5
but
not
scopolamine
(10
ip).
Pilocarpine
bicoherence
cross-frequency
(CFC)
slow
waves
(SW,
1-5
hippocampal
β,
waves,
stronger
CA1
alveus
CA3c
stratum
radiatum.
Bicoherence
further
revealed
nonlinear
interaction
CA1-alveus.
Beta
or
were
segregated
one
phase
OB-SW,
opposite
γ3
(100-160
suggesting
independent
β/γ1
versus
γ2/γ3
waves.
At
radiatum,
showed
decreased
theta
power,
theta-β
theta-γ2
CFC
baseline
walking,
SW
IMM,
pilocarpine.
It
concluded
γ
are
modulated
respiratory
rhythm,
behavior-dependent
manner,
functional
connectivity
frequencies
functions.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Oct. 12, 2024
Abstract
Episodic
memories
are
initially
encoded
in
the
hippocampus
and
subsequently
undergo
systems
consolidation
into
neocortex.
The
nature
of
memory
stored
neocortex
also
differs,
with
cortex
shown
to
encode
more
generalized
forms.
Although
several
brain
regions
known
social
information,
specific
cortical
circuits
involved
information
remain
unclear.
Using
vivo
Ca
2+
imaging
optogenetic
manipulations,
we
found
that
infralimbic
(IL)
neurons
projecting
nucleus
accumbens
shell
(IL
→NAcSh
)
store
consolidated
memory.
Inactivating
IL
responded
a
familiar
conspecific
impaired
recognition
other
mice
including
littermates,
demonstrating
these
neuronal
activities
support
familiarity.
Furthermore,
inactivating
hippocampal
ventral
CA1
disrupted
for
newly
familiarized
while
sparing
littermates.
These
findings
demonstrate
critical
role
hippocampal-cortical
interactions
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 17, 2024
Abstract
Genetically
encoded
calcium
(Ca
2+
)
indicators
(GECIs)
are
widely
used
for
imaging
neuronal
activity,
yet
current
limitations
of
existing
red
fluorescent
GECIs
have
constrained
their
applicability.
The
inherently
dim
fluorescence
and
low
signal-to-noise
ratio
red-shifted
posed
significant
challenges.
More
critically,
several
red-fluorescent
exhibit
photoswitching
when
exposed
to
blue
light,
thereby
limiting
applicability
in
all-optical
experimental
approaches.
Here,
we
present
the
development
PinkyCaMP,
first
mScarlet-based
Ca
sensor
that
outperforms
sensors
brightness,
photostability,
ratio,
compatibility
with
optogenetics
neurotransmitter
imaging.
PinkyCaMP
is
well-tolerated
by
neurons,
showing
no
toxicity
or
aggregation,
both
vitro
vivo
.
All
approaches,
including
single-photon
excitation
methods
such
as
fiber
photometry,
widefield
imaging,
miniscope
well
two-photon
awake
mice,
fully
compatible
PinkyCaMP.
