Structure and Evolution of Ribosomal Genes of Insect Chromosomes
Insects,
Journal Year:
2024,
Volume and Issue:
15(8), P. 593 - 593
Published: Aug. 4, 2024
Currently,
clusters
of
45S
and
5S
ribosomal
DNA
(rDNA)
have
been
studied
in
about
1000
100
species
the
class
Insecta,
respectively.
Although
number
insect
with
known
rDNA
(also
referred
to
as
nucleolus-organizing
regions,
or
NORs)
constitutes
less
than
0.1
percent
described
members
this
enormous
group,
certain
conclusions
can
already
be
drawn.
Since
haploid
karyotypes
single
predominate
both
basal
derived
groups,
character
state
is
apparently
ancestral
for
Insecta
general.
Nevertheless,
number,
chromosomal
location,
other
characteristics
sites
substantially
vary
across
different
species,
sometimes
even
within
same
species.
There
are
several
main
factors
molecular
mechanisms
that
either
maintain
these
parameters
alter
them
on
short-term
and/or
long-term
scale.
Chromosome
structure
(i.e.,
monocentric
vs.
holokinetic
chromosomes),
excessive
numbers
rRNA
gene
copies
per
cluster,
interactions
transposable
elements,
pseudogenization,
meiotic
recombination
perhaps
most
important
among
them.
Language: Английский
First Karyotype Description for Acanthognathus rudis Brown & Kempf, 1969 (Formicidae: Myrmicinae) with Notes on Its Natural History
Sociobiology,
Journal Year:
2024,
Volume and Issue:
71(3), P. e10778 - e10778
Published: Sept. 19, 2024
The
trap-jaw
ant
Acanthognathus
Mayr
(Myrmicinae:
Dacetina)
has
been
subject
of
various
studies
since
1969,
but
there
no
progress
in
its
cytogenetics.
This
study
describes
provides
the
first
karyotype
description
a
representative
genus,
A.
rudis,
including
chromosomal
number,
morphology,
and
distribution
repetitive
sequences.
A
colony
collected
Southeastern
Brazil
exhibited
diploid
number
2n
=
14
(12
metacentrics
+
2
submetacentrics),
lowest
among
Daceton
genus-group
Neotropical
this
group
to
be
karyologically
studied.
rDNA
clusters
were
located
pericentromeric
region
single
chromosome
pair,
(GA)n
blocks
present
only
terminal
regions
both
arms
euchromatic
regions,
(TTAGG)n
hybridized
with
telomeres
all
chromosomes,
without
interstitial
telomeric
sites.
sequence
patterns
align
those
observed
other
Formicidae.
Additionally,
we
documented
new
behavioral
aspects
mandible
use
rudis
workers
provided
images
immature
stages.
These
findings
emphasize
need
for
further
research
on
genus-group.
Language: Английский