bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2022,
Volume and Issue:
unknown
Published: Nov. 23, 2022
ABSTRACT
Chemosensory-driven
hostplant
specialization
is
a
major
force
mediating
insect
ecological
adaptation
and
speciation.
Drosophila
sechellia
,
species
endemic
to
the
Seychelles
islands,
feeds
oviposits
on
Morinda
citrifolia
almost
exclusively.
This
fruit
harmless
D.
but
toxic
other
Drosophilidae
including
closely
related
generalists
simulans
melanogaster
due
its
high
content
of
fatty
acids.
While
several
olfactory
adaptations
sechellia’s
preference
for
host
have
been
uncovered,
role
taste
has
much
less
examined.
We
found
that
reduced
feeding
aversion
bitter
compounds
acids
are
aversive
.
The
loss
canavanine,
coumarin,
arose
in
lineage,
as
sister
showed
responses
akin
those
melanogaster.
increased
towards
M.
These
results
line
with
genes
encoding
gustatory
receptors
(GRs)
two
GR
which
lost
GR39a.a
GR28b.a
influence
reduction
some
compounds.
Also,
appetite
prominent
acid
compound
relatives.
Our
support
hypothesis
changes
system,
specifically
sensitivity
deter
generalist
ancestors,
contribute
host.
Summary
statement
Taste
specializations
specialist
include
lineage-specific
associated
losses
receptors,
Noni
Proceedings of the Royal Society B Biological Sciences,
Journal Year:
2022,
Volume and Issue:
289(1989)
Published: Dec. 14, 2022
Among
the
many
wonders
of
nature,
sense
smell
fly
Drosophila
melanogaster
might
seem,
at
first
glance,
esoteric
interest.
Nevertheless,
for
over
a
century,
‘nose’
this
insect
has
been
an
extraordinary
system
to
explore
questions
in
animal
behaviour,
ecology
and
evolution,
neuroscience,
physiology
molecular
genetics.
The
insights
gained
are
relevant
our
understanding
sensory
biology
vertebrates,
including
humans,
other
species,
encompassing
those
detrimental
human
health.
Here,
I
present
overview
current
knowledge
D.
olfaction,
from
molecules
behaviours,
with
emphasis
on
historical
motivations
studies
illustration
how
technical
innovations
have
enabled
advances.
also
highlight
some
pressing
long-term
questions.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: Aug. 15, 2024
The
evolutionary
expansion
of
sensory
neuron
populations
detecting
important
environmental
cues
is
widespread,
but
functionally
enigmatic.
We
investigated
this
phenomenon
through
comparison
homologous
olfactory
pathways
Drosophila
melanogaster
and
its
close
relative
sechellia,
an
extreme
specialist
for
Morinda
citrifolia
noni
fruit.
D.
sechellia
has
evolved
species-specific
expansions
in
select,
noni-detecting
(OSN)
populations,
multigenic
changes.
Activation
inhibition
defined
proportions
neurons
demonstrate
that
OSN
number
increases
contribute
to
stronger,
more
persistent,
noni-odour
tracking
behaviour.
These
result
increased
synaptic
connections
with
their
projection
(PN)
partners,
which
are
conserved
between
species.
Surprisingly,
having
OSNs
does
not
lead
greater
odour-evoked
PN
sensitivity
or
reliability.
Rather,
pooling
exhibit
reduced
adaptation,
likely
weakened
lateral
inhibition.
Our
work
reveals
unexpected
functional
impact
population
explain
ecologically-relevant,
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 16, 2025
Sensory
neurons
must
be
reproducibly
specified
to
permit
accurate
neural
representation
of
external
signals
but
also
able
change
during
evolution.
We
studied
this
paradox
in
the
Drosophila
olfactory
system
by
establishing
a
single-cell
transcriptomic
atlas
all
developing
antennal
sensory
lineages,
including
latent
populations
that
normally
undergo
programmed
cell
death
(PCD).
This
reveals
transcriptional
control
is
robust,
imperfect,
defining
selective
receptor
expression.
A
second
layer
precision
afforded
intersection
expression
functionally-interacting
subunits.
third
defined
stereotyped
PCD
patterning,
which
masks
promiscuous
fated
die
and
removes
"empty"
lacking
receptors.
Like
choice,
under
lineage-specific
control;
promiscuity
regulation
leads
previously-unappreciated
heterogeneity
neuronal
numbers.
Thus
functional
mature
belies
developmental
noise
might
facilitate
evolution
pathways.
Molecular Ecology,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 21, 2025
ABSTRACT
Eurasian
spruce
bark
beetle
Ips
typographus
,
a
natural
part
of
forest
ecosystems,
is
major
threat
to
Norway
forests
during
outbreaks.
Olfaction
plays
crucial
role
in
the
survival
and
range
expansion
these
beetles,
amid
disturbances
climate
change.
As
current
management
strategies
are
suboptimal
for
controlling
outbreaks,
reverse
chemical
ecology
approaches
based
on
pheromone
receptors
offer
promising
alternatives.
While
search
progress,
recently
found
chromosomal
inversions
indicates
signs
adaptation
this
species.
Our
attempts
characterise
one
highly
expressed
odorant
receptors,
ItypOR33
located
an
inversion,
led
discovery
polymorphic
variants
distributed
with
similar
frequency
across
18
European
populations.
Deorphanizing
its
variant
ItypOR33a
using
Drosophila
empty‐neuron
system
(DeNS)
revealed
tuned
amitinol,
heterospecific
component
spp.,
whereas
(
S
)‐(−)‐ipsenol,
conspecific
I.
.
The
silico
structural
basis
variations
by
predicting
putative
ligand‐binding
sites,
tunnels
ligand‐receptor
interactions.
However,
no
sex‐specific
differences
were
expression,
ligand
amitinol
elicited
behavioural
electrophysiological
responses.
Reporting
population‐level
functional
olfactory
polymorphisms
first
time
non‐model
organism—bark
provides
key
evidence
further
exploring
their
forests.
Additionally,
findings
indicate
potential
long‐term
complexities
managing
beetles
Journal of Experimental Biology,
Journal Year:
2023,
Volume and Issue:
226(3)
Published: Jan. 13, 2023
ABSTRACT
Chemosensory-driven
host
plant
specialization
is
a
major
force
mediating
insect
ecological
adaptation
and
speciation.
Drosophila
sechellia,
species
endemic
to
the
Seychelles
islands,
feeds
oviposits
on
Morinda
citrifolia
almost
exclusively.
This
fruit
harmless
D.
sechellia
but
toxic
other
Drosophilidae,
including
closely
related
generalists
simulans
melanogaster,
because
of
its
high
content
fatty
acids.
While
several
olfactory
adaptations
sechellia’s
preference
for
have
been
uncovered,
role
taste
has
much
less
examined.
We
found
that
reduced
feeding
aversion
bitter
compounds
acids
are
aversive
melanogaster
simulans.
The
loss
canavanine,
coumarin
arose
in
lineage,
as
sister
showed
responses
akin
those
melanogaster.
increased
towards
M.
citrifolia.
These
results
line
with
genes
encode
gustatory
receptors
(GRs)
two
GR
which
lost
GR39a.a
GR28b.a,
influence
reduction
some
compounds.
Also,
appetite
prominent
acid
compound
relatives.
Our
support
hypothesis
changes
system,
specifically
sensitivity
deter
generalist
ancestors,
contribute
host.
