A
fundamental
question
in
sensory
processing
is
how
different
channels
of
input
are
processed
to
regulate
behavior.
Different
may
converge
onto
common
downstream
pathways
drive
the
same
behaviors,
or
they
activate
separate
distinct
behaviors.
We
investigated
this
Drosophila
bitter
taste
system,
which
contains
diverse
bitter-sensing
cells
residing
organs.
First,
we
optogenetically
activated
subsets
neurons
within
each
organ.
These
elicited
broad
and
highly
overlapping
behavioral
effects,
suggesting
that
pathways,
but
also
observed
differences
argue
for
biased
convergence.
Consistent
with
these
results,
transsynaptic
tracing
revealed
organs
connect
connectivity.
one
type
neuron
projects
higher
brain.
integrate
from
multiple
specific
taste-related
then
traced
circuits,
providing
first
glimpse
into
Together,
results
reveal
inputs
selectively
integrated
early
circuit,
enabling
pooling
information,
while
circuit
diverges
have
roles.
Insects
rely
on
a
family
of
seven
transmembrane
proteins
called
gustatory
receptors
(GRs)
to
encode
different
taste
modalities,
such
as
sweet
and
bitter.
We
report
structures
Nature Communications,
Год журнала:
2018,
Номер
9(1)
Опубликована: Окт. 8, 2018
Abstract
Through
analysis
of
the
Drosophila
ionotropic
receptors
(IRs),
a
family
variant
glutamate
receptors,
we
reveal
that
most
IRs
are
expressed
in
peripheral
neuron
populations
diverse
gustatory
organs
larvae
and
adults.
We
characterise
IR56d,
which
defines
two
anatomically-distinct
classes
proboscis:
one
responds
to
carbonated
solutions
fatty
acids
while
other
represents
subset
sugar-
acid-sensing
cells.
Mutational
indicates
together
with
broadly-expressed
co-receptors
IR25a
IR76b,
is
essential
for
physiological
responses
carbonation
acids,
but
not
sugars.
further
demonstrate
both
promote
IR56d-dependent
attraction
flies,
through
different
behavioural
outputs.
Our
work
provides
toolkit
investigating
taste
functions
IRs,
these
required
sensing,
illustrates
how
system
uses
combinatorial
expression
sensory
molecules
distinct
neurons
coordinate
behaviour.
Each
taste
modality
is
generally
encoded
by
a
single,
molecularly
defined,
population
of
sensory
cells.
However,
salt
stimulates
multiple
pathways
in
mammals
and
insects,
suggesting
more
complex
code
for
taste.
Here,
we
examine
coding
Drosophila.
After
creating
comprehensive
molecular
map
comprised
five
discrete
neuron
classes
across
the
fly
labellum,
find
that
four
are
activated
salt:
two
exhibiting
characteristics
‘low
salt’
cells,
‘high
classes.
Behaviorally,
low
attraction
depends
primarily
on
‘sweet’
neurons,
with
additional
input
from
neurons
expressing
ionotropic
receptor
IR94e.
High
avoidance
mediated
‘bitter’
glutamatergic
Ppk23.
Interestingly,
impact
these
prior
consumption.
These
results
support
model
flies
combinatorially
integrates
inputs
cell
types
to
afford
robust
flexible
behaviors.
Cell Reports,
Год журнала:
2019,
Номер
27(6), С. 1675 - 1685.e7
Опубликована: Май 1, 2019
Recent
studies
find
that
sugar
tastes
less
intense
to
humans
with
obesity,
but
whether
this
sensory
change
is
a
cause
or
consequence
of
obesity
unclear.
To
tackle
question,
we
study
the
effects
high
diet
on
sweet
taste
sensation
and
feeding
behavior
in
Drosophila
melanogaster.
On
diet,
fruit
flies
have
lower
responses
stimuli,
overconsume
food,
develop
obesity.
Excess
dietary
sugar,
not
sweetness
alone,
caused
deficits
overeating
via
cell-autonomous
action
sensor
O-linked
N-Acetylglucosamine
(O-GlcNAc)
transferase
(OGT)
sweet-sensing
neurons.
Correcting
by
manipulating
excitability
gustatory
neurons
levels
OGT
protected
animals
from
diet-induced
Our
work
demonstrates
reshaping
excess
drives
highlights
role
glucose
metabolism
neural
activity
behavior.
PLoS Biology,
Год журнала:
2019,
Номер
17(2), С. e3000162 - e3000162
Опубликована: Фев. 27, 2019
Feeding
preference
is
critical
for
insect
adaptation
and
survival.
However,
little
known
regarding
the
determination
of
feeding
preference,
genetic
basis
poorly
understood.
As
a
model
lepidopteran
with
economic
importance,
domesticated
silkworm,
Bombyx
mori,
well-known
monophagous
that
predominantly
feeds
on
fresh
mulberry
leaves.
This
species-specific
provides
an
excellent
investigation
host-plant
selection
insects,
although
molecular
mechanism
underlying
this
phenomenon
remains
unknown.
Here,
we
describe
gene
GR66,
which
encodes
putative
bitter
gustatory
receptor
(GR)
responsible
mulberry-specific
B.
mori.
With
aid
transposon-based,
clustered
regularly
interspaced
short
palindromic
repeats
(CRISPR)/CRISPR-associated
protein-9
nuclease
(Cas9)
system,
GR66
locus
was
genetically
mutated,
homozygous
mutant
silkworm
strains
truncated
66
(GR66)
proteins
were
established.
larvae
acquired
new
activity,
exhibiting
ability
to
feed
number
plant
species
in
addition
leaves,
including
fruits
grain
seeds
are
not
normally
consumed
by
wild-type
(WT)
silkworms.
Furthermore,
choice
assay
revealed
lost
their
specificity
mulberry.
Overall,
our
findings
provide
first
phenotypic
evidences
single
GR
major
factor
affecting
preference.
Female
Aedes
aegypti
mosquitoes
are
deadly
vectors
of
arboviral
pathogens
and
breed
in
containers
freshwater
associated
with
human
habitation.
Because
high
salinity
is
lethal
to
offspring,
correctly
evaluating
water
purity
a
crucial
parenting
decision.
We
found
that
the
DEG/ENaC
channel
ppk301
sensory
neurons
expressing
control
egg-laying
initiation
choice
Ae.
aegypti.
Using
calcium
imaging,
we
ppk301-expressing
cells
show
ppk301-dependent
responses
but,
unexpectedly,
also
respond
salt
ppk301-independent
fashion.
This
suggests
instructive
for
at
low-salt
concentrations,
but
pathway
responsible
inhibiting
high-salt
concentrations.
Water
key
resource
insect
survival
understanding
how
interact
different
behaviors
an
opportunity
study
evolution
chemosensory
systems.
