The
question
as
to
whether
animals
taste
cholesterol
is
not
resolved.
This
study
investigates
the
fruit
fly,
Drosophila
melanogaster
,
capable
of
detecting
through
their
gustatory
system.
We
found
that
flies
are
indifferent
low
levels
and
avoid
higher
levels.
avoidance
mediated
by
receptor
neurons
(GRNs),
demonstrating
can
cholesterol.
cholesterol-responsive
GRNs
comprise
a
subset
also
responds
bitter
substances.
Cholesterol
detection
depends
on
five
ionotropic
(IR)
family
members,
disrupting
any
these
genes
impairs
flies'
ability
Ectopic
expressions
IRs
in
reveals
two
classes
receptors,
each
with
three
shared
one
unique
subunit.
Additionally,
expressing
receptors
sugar-responsive
confers
attraction
cholesterol,
GRNs.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: April 25, 2024
Abstract
Amino
acid
availability
is
monitored
by
animals
to
adapt
their
nutritional
environment.
Beyond
gustatory
receptors
and
systemic
amino
sensors,
enteroendocrine
cells
(EECs)
are
believed
directly
percept
dietary
acids
secrete
regulatory
peptides.
However,
the
cellular
machinery
underlying
acid-sensing
EECs
how
EEC-derived
hormones
modulate
feeding
behavior
remain
elusive.
Here,
developing
tools
specifically
manipulate
EECs,
we
find
that
Drosophila
neuropeptide
F
(NPF)
from
mated
female
inhibits
feeding,
similar
human
PYY.
Mechanistically,
L-Glutamate
acts
through
metabotropic
glutamate
receptor
mGluR
decelerate
calcium
oscillations
in
thereby
causing
reduced
NPF
secretion
via
dense-core
vesicles.
Furthermore,
two
dopaminergic
enteric
neurons
expressing
NPFR
perceive
relay
an
anorexigenic
signal
brain.
Thus,
our
findings
provide
mechanistic
insights
into
assess
food
quality
identify
a
conserved
mode
of
action
explains
gut
NPF/PYY
modulates
intake.
iScience,
Journal Year:
2023,
Volume and Issue:
26(5), P. 106607 - 106607
Published: April 7, 2023
Increasing
pollution
of
heavy
metals
poses
great
risks
to
animals
globally.
Their
survival
likely
relies
on
an
ability
detect
and
avoid
harmful
metal
ions
(HMIs).
Currently,
little
is
known
about
the
neural
mechanisms
HMI
detection.
Here,
we
show
that
Drosophila
related
species
Drosophilidae
actively
toxic
HMIs
at
micromolar
concentrations.
The
high
sensitivity
biologically
relevant.
Particularly,
their
cadmium
as
most
bitter
substance,
denatonium.
Detection
in
food
requires
Gr66a+
gustatory
neurons
but
independent
bitter-taste
receptors.
In
these
neurons,
ionotropic
receptors
IR76b,
IR25a,
IR7a
are
required
for
perception
metals.
Furthermore,
IR47a
mediates
activation
a
distinct
group
non-Gr66a+
elicited
by
HMIs.
Together,
our
findings
reveal
surprising
taste
quality
represented
noxious
ions.
Molecules and Cells,
Journal Year:
2023,
Volume and Issue:
46(7), P. 451 - 460
Published: May 19, 2023
Animals
generally
prefer
nutrients
and
avoid
toxic
harmful
chemicals.Recent
behavioral
physiological
studies
have
identified
that
sweet-sensing
gustatory
receptor
neurons
(GRNs)
in
Drosophila
melanogaster
mediate
appetitive
behaviors
toward
fatty
acids.Sweet-sensing
GRN
activation
requires
the
function
of
ionotropic
receptors
IR25a,
IR56d,
IR76b,
as
well
GR64e.However,
we
reveal
hexanoic
acid
(HA)
is
rather
than
nutritious
to
D.
melanogaster.HA
one
major
components
fruit
Morinda
citrifolia
(noni).Thus,
analyzed
responses
noni
acids,
HA,
via
electrophysiology
proboscis
extension
response
(PER)
assay.Electrophysiological
tests
show
this
reminiscent
arginine-mediated
neuronal
responses.Here,
determined
a
low
concentration
HA
induced
attraction,
which
was
mediated
by
GRNs,
high
aversion,
bitter-sensing
GRNs.We
also
demonstrated
elicits
attraction
mainly
GR64d
IR56d
expressed
but
activates
three
(GR32a,
GR33a,
GR66a)
GRNs.The
mechanism
sensing
biphasic
dose
dependent
manner.Furthermore,
inhibit
sugar-mediated
like
other
bitter
compounds.Taken
together,
discovered
binary
HA-sensing
may
be
evolutionarily
meaningful
foraging
niche
insects.
Salt
(NaCl),
is
an
essential
nutrient
for
survival,
while
excessive
salt
can
be
detrimental.
In
the
fruit
fly,
Drosophila
melanogaster
,
internal
taste
organs
in
pharynx
are
critical
gatekeepers
impacting
decision
to
accept
or
reject
a
food.
Currently,
our
understanding
of
mechanism
through
which
pharyngeal
gustatory
receptor
neurons
(GRNs)
sense
high
rudimentary.
Here,
we
found
that
member
ionotropic
family,
Ir60b
expressed
exclusively
pair
GRNs
activated
by
salt.
Using
two-way
choice
assay
(DrosoX)
measure
ingestion
volume,
demonstrate
IR60b
and
two
co-receptors
IR25a
IR76b
required
prevent
consumption.
Mutants
lacking
external
but
retaining
exhibit
much
higher
avoidance
than
flies
with
all
missing
three
IRs.
Our
findings
highlight
vital
role
IRs
GRN
control
iScience,
Journal Year:
2024,
Volume and Issue:
27(6), P. 110087 - 110087
Published: May 23, 2024
Taste
organs
contain
distinct
gustatory
receptors
that
help
organisms
differentiate
between
nourishing
and
potentially
harmful
foods.
The
detection
of
high
pH
levels
plays
a
crucial
role
in
food
selection,
but
the
specific
responsible
for
perceiving
elevated
foods
have
remained
unknown.
By
using
STAR Protocols,
Journal Year:
2022,
Volume and Issue:
3(2), P. 101410 - 101410
Published: May 18, 2022
Food
preference
is
a
fundamental
behavior
for
animals
to
choose
nutritious
foods
while
rejecting
containing
toxins.
Here,
we
describe
binary
food
choice
assays
using
Drosophila
melanogaster,
which
are
straightforward
approaches
the
characterization
of
two-way
tastants.
We
detail
preparation
flies
and
dye-containing
food,
followed
by
binary-choice
feeding
determination
index
(PI).
This
protocol
simple,
sensitive,
reproducible
in
qualitatively
detecting
attractive
or
aversive
characteristics
toward
any
For
complete
details
on
use
execution
this
protocol,
please
refer
Aryal
et
al.
(2022).
