bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 17, 2024
Abstract
Co-evolution
between
cereals
and
pathogenic
grass
powdery
mildew
fungi
is
exemplified
by
sequence
diversification
of
an
allelic
series
barley
resistance
genes
encoding
Mildew
Locus
A
(MLA)
nucleotide-binding
leucine-rich
repeat
(NLR)
immunoreceptors
with
a
N-terminal
coiled-coil
domain
(CNLs).
Each
immunoreceptor
recognises
matching,
strain-specific
effector
encoded
avirulence
gene
(
AVR
)
.
We
present
here
the
cryo-EM
structure
MLA13
in
complex
its
cognate
A13
-1.
The
adopts
RNase-like
fold
when
bound
to
planta
,
similar
crystal
structures
other
e
ffectors
purified
from
E.
coli
-1
interacts
via
basal
loops
C-terminal
leucine
rich
repeats
(LRRs)
central
winged
helix
(WHD).
Co-expression
structure-guided
substitution
variants
show
that
receptor–effector
interface
plays
essential
role
mediating
immunity-associated
plant
cell
death.
Furthermore,
combining
structural
information
MLA13–AVR
heterocomplex
alignments
MLA
receptors,
we
designed
single
amino
acid
MLA7
enables
expanded
detection
virulent
variant
-V2.
In
contrast
pentameric
conformation
previously
reported
effector-activated
CNL
resistosomes,
was
resolved
as
stable
heterodimer
expression
system.
Our
study
suggests
might
represent
output
distinct
resistosomes
highlights
opportunities
for
development
designer
gain-of-function
NLRs.
Nature,
Год журнала:
2022,
Номер
610(7932), С. 532 - 539
Опубликована: Сен. 26, 2022
Abstract
Plant
intracellular
nucleotide-binding
leucine-rich
repeat
receptors
(NLRs)
detect
pathogen
effectors
to
trigger
immune
responses
1
.
Indirect
recognition
of
a
effector
by
the
dicotyledonous
Arabidopsis
thaliana
coiled-coil
domain
containing
NLR
(CNL)
ZAR1
induces
formation
large
hetero-oligomeric
protein
complex,
termed
resistosome,
which
functions
as
calcium
channel
required
for
ZAR1-mediated
immunity
2–4
Whether
resistosome
and
activities
are
conserved
among
plant
CNLs
remains
unknown.
Here
we
report
cryo-electron
microscopy
structure
wheat
CNL
Sr35
5
in
complex
with
AvrSr35
6
stem
rust
pathogen.
Direct
binding
repeats
results
pentameric
Sr35–AvrSr35
term
resistosome.
Wheat
resistosomes
bear
striking
structural
similarities,
including
an
arginine
cluster
not
previously
recognized
conserved,
co-occurs
forms
intramolecular
interactions
'EDVID'
motif
domain.
Electrophysiological
measurements
show
that
exhibits
non-selective
cation
activity.
These
insights
allowed
us
generate
new
variants
closely
related
barley
orphan
NLRs
recognize
AvrSr35.
Our
data
support
evolutionary
conservation
plants
demonstrate
proof
principle
structure-based
engineering
crop
improvement.
Abstract
Plant
pathogens
compromise
crop
yields.
Plants
have
evolved
robust
innate
immunity
that
depends
in
part
on
intracellular
Nucleotide‐binding,
Leucine
rich‐Repeat
(NLR)
immune
receptors
activate
defense
responses
upon
detection
of
pathogen‐derived
effectors.
Most
“sensor”
NLRs
detect
effectors
require
the
activity
“helper”
NLRs,
but
how
helper
support
sensor
NLR
function
is
poorly
understood.
Many
Solanaceae
NRC
(NLR‐Required
for
Cell
death)
class
NLRs.
We
show
here
Rpi‐amr3,
a
from
Solanum
americanum
,
detects
AVRamr3
potato
late
blight
pathogen,
Phytophthora
infestans
and
activates
oligomerization
NRC2
NRC4
into
high‐molecular‐weight
resistosomes.
In
contrast,
recognition
P.
effector
AVRamr1
by
another
Rpi‐amr1
induces
formation
only
resistosome.
The
activated
oligomer
becomes
enriched
membrane
fractions.
ATP‐binding
motifs
both
Rpi‐amr3
are
required
resistosome
formation,
not
interaction
with
its
cognate
effector.
can
be
homologs
other
species.
Mechanistic
understanding
will
underpin
engineering
crops
durable
disease
resistance.
Plants
coordinately
use
cell-surface
and
intracellular
immune
receptors
to
perceive
pathogens
mount
an
response.
Intracellular
events
of
pathogen
recognition
are
largely
mediated
by
the
nucleotide
binding
leucine
rich-repeat
(NLR)
classes.
Upon
perception,
NLRs
trigger
a
potent
broad-spectrum
reaction,
usually
accompanied
form
programmed
cell
death
termed
hypersensitive
Some
plant
act
as
multifunctional
singleton
which
combine
detection
signaling.
However,
can
also
function
in
higher
order
pairs
networks
functionally
specialized
interconnected
receptors.
In
this
article,
we
cover
basic
aspects
NLR
biology
with
emphasis
on
networks.
We
highlight
some
recent
advances
structure,
function,
activation
discuss
emerging
topics
such
modulator
NLRs,
suppression
bioengineering.
Multi-disciplinary
approaches
required
disentangle
how
these
receptor
evolve.
Answering
questions
holds
potential
deepen
our
understanding
system
unlock
new
era
disease
resistance
breeding.
The Plant Cell,
Год журнала:
2024,
Номер
36(5), С. 1465 - 1481
Опубликована: Янв. 23, 2024
Abstract
Plant
diseases
are
a
constant
and
serious
threat
to
agriculture
ecological
biodiversity.
Plants
possess
sophisticated
innate
immunity
system
capable
of
detecting
responding
pathogen
infection
prevent
disease.
Our
understanding
this
has
grown
enormously
over
the
past
century.
Early
genetic
descriptions
plant
disease
resistance
virulence
were
embodied
in
gene-for-gene
hypothesis,
while
physiological
studies
identified
pathogen-derived
elicitors
that
could
trigger
defense
responses
cells
tissues.
Molecular
these
phenomena
have
now
coalesced
into
an
integrated
model
involving
cell
surface
intracellular
detection
specific
molecules
proteins
culminating
induction
various
cellular
responses.
Extracellular
receptors
engage
distinct
signaling
processes
but
converge
on
many
similar
outputs
with
substantial
evidence
for
integration
pathways
interdependent
networks
controlling
outcomes.
Many
molecular
details
recognition
known,
providing
opportunities
bioengineering
enhance
protection
from
Here
we
provide
overview
current
main
principles
immunity,
emphasis
key
scientific
milestones
leading
insights.
Nature,
Год журнала:
2024,
Номер
632(8026), С. 869 - 876
Опубликована: Июнь 12, 2024
Abstract
Nucleotide-binding
leucine-rich
repeat
(NLR)
proteins
play
a
pivotal
role
in
plant
immunity
by
recognizing
pathogen
effectors
1,2
.
Maintaining
balanced
immune
response
is
crucial,
as
excessive
NLR
expression
can
lead
to
unintended
autoimmunity
3,4
Unlike
most
NLRs,
the
required
for
cell
death
2
(NRC2)
belongs
small
group
characterized
constitutively
high
without
self-activation
5
The
mechanisms
underlying
NRC2
autoinhibition
and
activation
are
not
yet
understood.
Here
we
show
that
Solanum
lycopersicum
(tomato)
(
Sl
NRC2)
forms
dimers
tetramers
higher-order
oligomers
at
elevated
concentrations.
Cryo-electron
microscopy
shows
an
inactive
conformation
of
these
oligomers.
Dimerization
oligomerization
only
stabilize
state
but
also
sequester
from
assembling
into
active
form.
Mutations
dimeric
or
interdimeric
interfaces
enhance
pathogen-induced
Nicotiana
benthamiana
cryo-electron
structures
unexpectedly
inositol
hexakisphosphate
(IP
6
)
pentakisphosphate
bound
inner
surface
C-terminal
domain
NRC2,
confirmed
mass
spectrometry.
phosphate-binding
site
impair
phosphate
binding
NRC2-mediated
N.
Our
study
indicates
negative
regulatory
mechanism
suggests
phosphates
cofactors
NRCs.
Plants
deploy
cell-surface
and
intracellular
receptors
to
detect
pathogen
attack
trigger
innate
immune
responses.
Inside
host
cells,
families
of
nucleotide-binding/leucine-rich
repeat
(NLR)
proteins
serve
as
sensors
or
downstream
mediators
defence
outputs
cell
death,
which
prevent
disease.
Established
genetic
underpinnings
NLR-mediated
immunity
revealed
various
strategies
plants
adopt
combat
rapidly
evolving
microbial
pathogens.
The
molecular
mechanisms
NLR
activation
signal
transmission
components
controlling
execution
were
less
clear.
Here,
we
review
recent
protein
structural
biochemical
insights
plant
sensor
signalling
functions.
When
put
together,
the
data
show
how
different
families,
whether
transducers,
converge
on
nucleotide-based
second
messengers
cellular
calcium
confer
immunity.
Although
pathogen-activated
NLRs
in
engage
plant-specific
machineries
promote
defence,
comparisons
with
mammalian
receptor
counterparts
highlight
some
shared
working
principles
for
across
kingdoms.