As
represented
by
gynandromorphs
(sexually
mosaic
individuals),
sexual
differentiation
in
insects
proceeds
primarily
cell
autonomously
depending
on
sex
chromosomes.
Insect
determination
systems,
although
dominated
male
heterogamety,
are
highly
diverse.
Dragonflies
and
damselflies
(the
order
Odonata)
the
most
ancestral
winged
have
heterogametic
systems.
Some
species
(e.g.,
Crocothemis
servilia)
intraspecific
polymorphisms
their
karyotypes,
such
as
switching
from
X0
to
neo-XY
chromosome
system
fusion.
In
dragonflies
damselflies,
adults
of
many
exhibit
color
dimorphism,
transition
upon
adult
maturation,
within
same
sex.
Molecular
mechanisms
underlying
been
investigated
extensively
fruit
fly
Drosophila
melanogaster,
but
recent
studies
revealed
that
upstream
genes
insect
cascade
Most
sex-specific
isoforms
for
doublesex
(dsx)
gene,
which
is
important
differentiation,
dsx
gene
plays
roles
masculinization
not
only
males
also
androchrome
females
damselfly
Ischnura
senegalensis.
this
review,
current
knowledge
summarized,
with
particular
focus
insects,
damselflies.
Frontiers in Insect Science,
Journal Year:
2023,
Volume and Issue:
3
Published: May 9, 2023
Unveiling
the
proximate
mechanism
of
caste
differentiation
is
crucial
for
understanding
insect
social
evolution,
and
gene
function
analysis
an
important
tool
in
this
endeavor.
The
RNA
interference
(RNAi)
technique
useful
termites,
but
its
knockdown
effects
may
differ
among
species.
One
most
model
species
field
termite
sociogenomics
Reticulitermes
speratus
Kolbe
(Isoptera:
Rhinotermitidae).
Presoldier
worker
can
be
artificially
induced
by
juvenile
hormone
20-hydroxyecdysone
application,
respectively.
However,
appropriate
RNAi
genes
expressed
during
has
never
been
considered.
To
clarify
issue,
first,
we
injected
nine
different
volumes
nuclease-free
water
(NFW,
0–404.8
nL)
into
workers
found
that
survival
rates
were
strongly
reduced
application
top
three
largest
volumes.
Second,
double-stranded
(ds)
ecdysone
receptor
homolog
(
RsEcR
)
(2.0
µg/151.8
nL
NFW)
with
treatments.
expression
levels
significantly
at
9
days
after
dsRNA
injection.
affected
both
molting
events
presoldier
present
results
highlight
need
caution
regarding
injection
experiments
using
We
suggest
solution
(2
µg;
approximately
100–200
suitable
R.
.
Frontiers in Ecology and Evolution,
Journal Year:
2022,
Volume and Issue:
10
Published: June 27, 2022
The
organization
of
social
insect
colonies
requires
sophisticated
mechanisms
to
regulate
caste
composition
according
colony
demands.
In
termites,
the
soldier
is
responsible
for
inhibition
differentiation,
but
mechanism
underlying
regulation
differentiation
still
unclear.
this
study,
we
performed
transcriptome
analyses
identify
genes
expressed
in
workers
that
fluctuated
presence
soldiers
subterranean
termite
Reticulitermes
speratus
.
First,
was
artificially
induced
via
juvenile
hormone
(JH)
application,
and
inhibitory
effects
on
were
evaluated.
Second,
transcriptomes
prepared
from
with
or
without
under
JH
treatment,
expression
differentially
(DEGs)
each
treatment.
levels
several
DEGs
verified
by
quantitative
real-time
PCR.
results
indicated
only
a
small
number
upregulated
soldiers.
A
homology
search
gene
ontology
(GO)
analysis
showed
some
levels,
interaction,
response
xenobiotic
substances,
suggesting
they
could
be
involved
developmental
arrest
pheromonal
workers.
Moreover,
GO
many
genes,
including
those
metabolic
processes,
application.
Suppression
accomplished
large
required
differentiation.
Frontiers in Ecology and Evolution,
Journal Year:
2023,
Volume and Issue:
10
Published: Jan. 6, 2023
Selfish
genetic
elements
(SGEs)
increase
their
transmission
efficiency
relative
to
the
rest
of
individual
genome,
which
is
often
deleterious
fitness.
Theoretical
studies
have
suggested
that
intragenomic
conflict
over
sex
ratio
distortion
between
SGEs
and
genome
should
lead
evolution
sex-determining
systems.
However,
in
insects,
there
are
relatively
few
other
than
those
on
Dipterans,
makes
it
difficult
understand
role
insect
determination.
This
partially
due
difficulties
observing
under
field
conditions.
The
effect
masked
by
counter-evolution
resistance
genes.
Interpopulation
cross-breeding
experiments
effective
detect
If
these
populations
different
genes,
reveal
existence
collapsing
evolutionary
antagonistic
state.
Ryukyu
drywood
termites
Neotermes
sugioi
,
distributed
Islands,
show
male-biased
ratios
pseudergates,
nymphs,
alates
soldiers
both
Okinawa
Ishigaki
but
degrees
bias
been
reported
islands.
Male-specific
microsatellite
alleles
this
species,
allowed
us
identify
eggs
young
larvae.
In
study,
we
used
locus
with
male-specific
investigate
primary
colonies
islands
offspring
obtained
through
were
not
Ishigaki.
Cross-breeding
showed
males
tend
a
offspring,
do
not.
result
consistent
hypothesis
male
species
caused
SGEs,
even
though
phylogenetically
distant
from
Diptera.
Accumulation
knowledge
conflicts
wide
range
taxa
might
be
an
important
step
toward
elucidating
mechanisms
diversification
determination
systems
insects.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2024,
Volume and Issue:
unknown
Published: May 8, 2024
ABSTRACT
The
molecular
mechanism
of
sex
determination
has
long
been
considered
conserved
in
insects.
However,
recent
studies
hemimetabolous
insects
have
challenged
this
notion.
One
notable
example
is
termites.
In
Reticulitermes
speratus
,
a
homolog
gene,
Doublesex
(
RsDsx
),
exhibits
characteristics
that
are
distinct
from
those
other
insects,
including
sister-group
cockroaches.
It
comprises
single
exon,
contains
only
doublesex/mab-3
DNA-binding
domain
(DM)
but
lacks
oligomerization
(OD),
and
transcriptional
activity
males.
To
investigate
whether
these
widespread
within
the
termite
lineage,
we
identified
Dsx
homologs
three
different
families.
loss
OD
sequences
was
observed
all
species
examined,
whereas
number
exons
expression
patterns
between
sexes
varied
among
Particularly,
distinctive
differences
were
found
Archotermopsidae
Kalotermitidae,
both
which
linear
caste
developmental
pathway.
Our
findings
indicate
diversification
structure
may
contributed
to
ecological
diversification,
such
as
pathways,
lineage.
Comparative Biochemistry and Physiology Part D Genomics and Proteomics,
Journal Year:
2024,
Volume and Issue:
52, P. 101297 - 101297
Published: July 22, 2024
The
molecular
mechanism
of
sex
determination
has
long
been
considered
conserved
in
insects.
However,
recent
studies
hemimetabolous
insects
have
challenged
this
notion.
One
notable
example
is
termites.
In
Reticulitermes
speratus,
a
homolog
gene,
Doublesex
(RsDsx),
exhibits
characteristics
that
are
distinct
from
those
other
insects,
including
sister-group
cockroaches.
It
comprises
single
exon,
contains
only
doublesex/mab-3
DNA-binding
domain
(DM)
but
lacks
oligomerization
(OD),
and
transcriptional
activity
males.
To
investigate
whether
these
widespread
within
the
termite
lineage,
we
identified
Dsx
homologs
three
different
families.
absence
OD
sequences
was
observed
all
species
examined,
whereas
number
exons
expression
patterns
between
sexes
varied
among
Particularly,
distinctive
differences
were
found
Archotermopsidae
Kalotermitidae,
both
which
linear
caste
developmental
pathway.
Our
findings
indicate
diversification
structure
may
contributed
to
ecological
diversification,
such
as
pathways,
lineage.
PLoS ONE,
Journal Year:
2024,
Volume and Issue:
19(10), P. e0311836 - e0311836
Published: Oct. 7, 2024
To
understand
the
mechanisms
underlying
social
evolution
and
caste
development
in
insects,
caste-specific
organs
genes
should
be
investigated.
In
rhinotermitid
termite,
Reticulitermes
speratus
,
lipocalin
gene
RS008881
which
encodes
a
protein
transporter,
is
expressed
ovarian
accessory
glands
of
primary
queens.
obtain
additional
data
on
its
expression
product
localization,
we
conducted
real-time
quantitative
polymerase
chain
reaction
assays
using
peptide
antibody.
Gene
analysis
castes
revealed
that
was
highly
female
secondary
reproductives.
Further
during
reproductive
differentiation
showed
levels
increased
prior
to
molting
into
individuals,
even
winged
imago
(alates)
stage.
Western
blotting
fluorescent
immunohistochemical
staining
localized
ovary
as
well
eggshells
produced
by
may
play
significant
role
biology
R
.
;
localization
both
eggshell
suggests
multiple
functions
related
embryo
protection
potential
pheromone
interactions.
IntechOpen eBooks,
Journal Year:
2022,
Volume and Issue:
unknown
Published: June 24, 2022
This
book
provides
contributions
on
various
topics
pertaining
to
arthropods
(insects
and
non-insects)
written
by
experts
in
their
respective
fields.
It
targets
a
wide
audience
of
entomologists,
biologists,
ecologists,
zoologists,
teachers,
students.
The
is
divided
into
four
main
sections
"Development",
"Food
Detection
Feeding
Behavior",
"Vector-borne
Diseases",
"Structure
Function
Vision".
Chapters
address
such
as
larval
development
metamorphosis
non-insect
arthropods,
spatiotemporal
dynamics
the
silver
leaf
whitefly
pest,
importance
three
species
household
cockroaches,
lac
insects
that
secrete
resin
worthy
industrial
importance,
feeding
behavior
some
insects,
much
more.
IntechOpen eBooks,
Journal Year:
2022,
Volume and Issue:
unknown
Published: June 24, 2022
In
insects,
metamorphosis
is
one
of
the
most
important
research
topics.
Their
drastic
morphological
and
physiological
changes
from
larvae
to
pupae,
then
adults,
have
fascinated
many
people.
These
changing
life
history
patterns
are
tightly
regulated
by
two
endocrine
systems,
ecdysteroids
(molting
hormones)
juvenile
hormones.
Metamorphosis
also
universal
phenomenon
in
non-insect
arthropods
(especially
crustaceans).
Additionally,
as
dwarf
males
(e.g.,
barnacle
crustaceans)
show
distinct
sexual
dimorphism
during
larval
developmental
stage,
development
differentiation
intimately
associated.
Our
knowledge
endocrinology
gene
cascades
underlying
rudimentary
at
best
relies
heavily
on
well-studied
insect
models.
Advances
newly
developed
applications,
omics
technologies
gene-targeting,
expected
lead
explorative
molecular
studies
that
reveal
components
pathways
unique
arthropods.
This
chapter
reconciles
known
reflects
our
findings
insects
outline
future
research.
