Single-stranded
DNA
binding
proteins
(SSBs)
are
ubiquitous
across
all
domains
of
life
and
play
essential
roles
via
stabilizing
protecting
single-stranded
(ss)
as
well
organizing
multiprotein
complexes
during
replication,
recombination,
repair.
Two
mammalian
SSB
paralogs
(hSSB1
hSSB2
in
humans)
were
recently
identified
shown
to
be
involved
various
genome
maintenance
processes.
Following
our
recent
discovery
the
liquid-liquid
phase
separation
(LLPS)
propensity
Escherichia
coli
(Ec)
SSB,
here
we
show
that
also
forms
LLPS
condensates
under
physiologically
relevant
ionic
conditions.
Similar
seen
for
EcSSB,
demonstrate
contribution
hSSB2's
C-terminal
intrinsically
disordered
region
(IDR)
condensate
formation,
selective
enrichment
metabolic
condensates.
However,
contrast
EcSSB-driven
is
inhibited
by
ssDNA
binding,
requires
nucleic
acid
especially
facilitated
ssDNA.
Our
results
reveal
an
evolutionarily
conserved
role
SSB-mediated
spatiotemporal
organization
complexes.
At
same
time,
differential
features
EcSSB
point
functional
adaptations
prokaryotic
versus
eukaryotic
contexts.
Molecular Biology of the Cell,
Год журнала:
2024,
Номер
35(5)
Опубликована: Апрель 3, 2024
The
SARS-CoV-2
nucleocapsid
(N)
protein
is
crucial
for
virus
replication
and
genome
packaging.
N
forms
biomolecular
condensates
both
in
vitro
vivo
a
process
known
as
liquid–liquid
phase
separation
(LLPS),
but
the
exact
factors
regulating
LLPS
of
are
not
fully
understood.
Here,
we
show
that
pH
buffer
choice
have
profound
impact
on
protein.
degree
highly
dependent
solution,
which
correlated
with
histidine
protonation
Specifically,
demonstrate
H356
essential
phosphate
buffer.
Moreover,
electrostatic
interactions
molecules
specific
amino
acid
residues
able
to
alter
net
charge
protein,
thus
influencing
its
ability
undergo
presence
RNA.
Overall,
these
findings
reveal
even
subtle
changes
or
surface
caused
by
system
can
strongly
influence
behavior,
point
main
driving
forces
separation.
Further,
our
emphasize
importance
experimental
parameters
when
studying
biomolecules,
especially
context
viral
infections
where
intracellular
milieu
undergoes
drastic
normally
decreases.
Frontiers in Immunology,
Год журнала:
2023,
Номер
14
Опубликована: Май 10, 2023
Spatiotemporal
separation
of
cellular
components
is
vital
to
ensure
biochemical
processes.
Membrane-bound
organelles
such
as
mitochondria
and
nuclei
play
a
major
role
in
isolating
intracellular
components,
while
membraneless
(MLOs)
are
accumulatively
uncovered
via
liquid-liquid
phase
(LLPS)
mediate
spatiotemporal
organization.
MLOs
orchestrate
various
key
processes,
including
protein
localization,
supramolecular
assembly,
gene
expression,
signal
transduction.
During
viral
infection,
LLPS
not
only
participates
replication
but
also
contributes
host
antiviral
immune
responses.
Therefore,
more
comprehensive
understanding
the
roles
virus
infection
may
open
up
new
avenues
for
treating
infectious
diseases.
In
this
review,
we
focus
on
defense
mechanisms
innate
immunity
discuss
involvement
during
evasion
escape,
well
strategy
targeting
treat
Acta Biochimica et Biophysica Sinica,
Год журнала:
2023,
Номер
55(7), С. 1099 - 1118
Опубликована: Июнь 14, 2023
Liquid-liquid
phase
separation
(LLPS)
has
emerged
as
a
crucial
mechanism
for
cellular
compartmentalization.
One
prominent
example
of
this
is
the
stress
granule.
Found
in
various
types
cells,
granule
biomolecular
condensate
formed
through
separation.
It
comprises
numerous
RNA
and
RNA-binding
proteins.
Over
past
decades,
substantial
knowledge
been
gained
about
composition
dynamics
granules.
SGs
can
regulate
signaling
pathways
have
associated
with
human
diseases,
such
neurodegenerative
cancer,
infectious
diseases.
The
threat
viral
infections
continues
to
loom
over
society.
Both
DNA
viruses
depend
on
host
cells
replication.
Intriguingly,
many
stages
life
cycle
are
closely
tied
metabolism
cells.
field
condensates
rapidly
advanced
recent
times.
In
context,
we
aim
summarize
research
granules
their
link
infections.
Notably,
triggered
by
behave
differently
from
canonical
sodium
arsenite
(SA)
heat
shock.
Studying
context
could
offer
valuable
platform
replication
processes
anti-viral
responses.
A
deeper
understanding
these
biological
pave
way
innovative
interventions
treatments
They
potentially
bridge
gap
between
basic
interactions
hosts.
Acta Biochimica et Biophysica Sinica,
Год журнала:
2023,
Номер
55(7), С. 1133 - 1152
Опубликована: Июль 1, 2023
Membrane-less
organelles
(MLOs)
formed
through
liquid-liquid
phase
separation
(LLPS)
are
associated
with
numerous
important
biological
functions,
but
the
abnormal
will
also
dysregulate
physiological
processes.
Emerging
evidence
points
to
importance
of
LLPS
in
human
health
and
diseases.
Nevertheless,
despite
recent
advancements,
our
knowledge
molecular
relationship
between
diseases
is
frequently
incomplete.
In
this
review,
we
outline
current
understanding
about
how
aberrant
affects
developmental
disorders,
tandem
repeat
cancers
viral
infection.
We
examine
disease
mechanisms
driven
by
condensates,
highlight
potential
treatment
approaches.
This
study
seeks
expand
providing
a
valuable
new
paradigm
for
as
well
further
translate
regarding
into
therapeutic
discoveries.
Nucleic Acids Research,
Год журнала:
2023,
Номер
52(5), С. 2290 - 2305
Опубликована: Дек. 19, 2023
Abstract
Phase
separation
regulates
fundamental
processes
in
gene
expression
and
is
mediated
by
the
local
concentration
of
proteins
nucleic
acids,
as
well
acid
secondary
structures
such
G-quadruplexes
(G4s).
These
play
roles
both
host
viral
replication
due
to
their
peculiar
localisation
regulatory
sequences.
Hepatitis
B
virus
(HBV)
covalently
closed
circular
DNA
(cccDNA)
an
episomal
minichromosome
whose
persistence
at
basis
chronic
infection.
Identifying
mechanisms
controlling
its
transcriptional
activity
indispensable
develop
new
therapeutic
strategies
against
hepatitis
B.
The
aim
this
study
was
determine
whether
G4s
are
formed
cccDNA
regulate
replication.
Combining
biochemistry
functional
studies,
we
demonstrate
that
indeed
contains
ten
structures.
Furthermore,
mutations
disrupting
two
located
enhancer
I
HBV
region
altered
transcription
Finally,
showed
for
first
time
undergoes
phase
a
G4-dependent
manner
promote
infected
hepatocytes.
Altogether,
our
data
give
insight
regulation
might
pave
way
identification
novel
targets
destabilize
or
silence
cccDNA.
Abstract
HIV-1
initiates
replication
by
its
transactivator
Tat,
hijacking
the
positive
transcription
elongation
factor
b
(P-TEFb)
in
host
cell.
Most
P-TEFb
is
maintained
an
inactive
state
7SK
snRNP
until
it
brought
to
initiation
complex
cellular
or
viral
transactivators
that
accelerate
and
facilitate
production
of
full-length
transcripts.
Here,
we
report
infection
triggers
liquid-liquid
phase
separation
LARP7,
a
central
component
snRNP.
Tat
incorporated
into
HIV-1-induced
LARP7
condensates
after
infection.
Conserved
lysine
residues
intrinsically
disordered
region
are
essential
for
both
inhibition
Tat-mediated
transcription.
These
findings
identify
mechanism
wherein
sequestered
within
condensates,
restraining
Journal of Virology,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 27, 2025
ABSTRACT
Pseudorabies
virus
(PRV)
is
a
porcine
alphaherpesvirus
that
can
infect
different
animal
species
and
cause
pruritus
lethal
encephalitis.
Stress
granules
(SGs)
are
membrane-free
cytoplasmic
structures
formed
by
liquid-liquid
phase
separation
of
G3BP
proteins
during
cell
translation
inhibition,
which
generally
plays
an
antiviral
role
in
various
viral
infections.
In
this
study,
we
found
infection
with
PRV
strains
inhibits
the
formation
SGs
host
cells.
We
IE180,
only
immediate
early
protein
PRV,
has
distinct
inhibitory
effect
on
SG
colocalizes
SG-nucleating
(G3BP1/2)
nucleus
infection.
Co-immunoprecipitation
assays
demonstrated
interaction
between
IE180
G3BP1/G3BP2,
appears
to
depend
Herpesvirus
ICP4-like
N-terminal
(ICP4L-N)
domain
both
NTF2L
RBD
domains
G3BP1.
Since
G3BPs
mainly
function
cytoplasm
induce
formation,
constructed
several
truncations
lacking
nuclear
localization
sequence
alter
subcellular
cytoplasm.
Mutant
was
expressed
still
suppressed
induced
arsenite
or
poly(I:C),
but
its
ability
inhibit
weakened.
Importantly,
knockout
facilitated
replication
H1299
cells,
while
exogenous
expression
wild-type
cells
replication.
summary,
our
study
indicates
suppresses
hijacks
into
benefit
IMPORTANCE
Herpesviruses,
including
pseudorabies
(PRV),
have
evolved
strategies
compromise
immune
responses.
one
targets
viruses
overcome
order
increase
The
related
herpes
simplex
1
(HSV-1)
promote
replication,
underlying
mechanisms
remain
unknown.
confirmed
formation.
Interestingly,
interacts
these
prevent
line
G3BP1/2
significantly
compromised
reported
mechanism
be
also
utilized
HSV-1
Therefore,
elucidates
novel
alphaherpesviruses
provides
new
perspective
inquire
escape
other
alphaherpesviruses.
ACS Infectious Diseases,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 4, 2025
We
observed
a
high
proportion
of
proteins
in
pathogenic
Mycobacterium
species
that
can
potentially
undergo
liquid-liquid
phase
separation
(LLPS)
mediated
biomolecular
condensate
formation,
compared
to
nonpathogenic
species.
These
mainly
include
the
PE-PPE
and
PE-PGRS
families
have
nucleic
acid
protein-protein
binding
functions,
typical
LLPS
proteins.
also
mapped
identified
M.
tuberculosis
(M.tb)
drug-resistant
databases
PubMLST
TBProfiler,
based
upon
WHO
2023
catalogue
resistance-associated
mutations.
High
sequence
conservation
LLPS-associated
various
multiple
M.tb
isolates
points
their
important
role
virulence
host-pathogen
interactions
during
evolution.
This
analysis
provides
perspective
on
protein
evaluation
pathogenesis
offers
avenues
for
future
research
aimed
at
developing
innovative
strategies
combat
infection.