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Figure Legends
Figure 1: MAMP
pre-treatment protects Fv/Fm from
bacterial induced suppression. A. Graph quantifying changes inFv/Fm over 23 hpi with DC3000
infection on Col-0 leaves. Blue line represents leaves pre-treated with
H2O; orange - pre-treated with chitin (100 µg/ml);
dashed grey - leaves pre-treated with flg22 (1 µM) and dashed yellow -
leaves pre-treated with elf18 (1 µM). B. 18 hpi imageFv/Fm of a Col-0 plant
pre-treated with H2O, chitin (100 µg/ml), flg22 (1 µM)
and elf18 (1 µM) at 18 hpi with DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .C. Graph quantifying changes inFv/Fm over 24 h following DC3000
infection on Col-0 and efr1 leaves. Blue line represents Col-0
leaves pre-treated with H2O; grey - Col-0 leaves
pre-treated with flg22 (1 µM); yellow - Col-0 leaves pre-treated with
elf18 (1 µM); green - efr1 leaves pre-treated with
H2O; dashed blue - efr1 leaves pre-treated with
flg22 (1 µM) and red - efr1 leaves pre-treated with elf18 (1 µM).D. Visual snapshot ofFv/Fm for a Col-0 plant (top
right) and efr1 plants pre-treated with H2O,
flg22 (1 µM) and elf18 (1 µM) at 18 hpi with DC3000. Orange represents
normal Fv/Fm , whereas
yellow/green/blue represents suppressedFv/Fm . E. Graph
quantifying changes in Fv/Fm over
24 h of DC3000 infection on Col-0 and cerk1-2 leaves. Blue
represent Col-0 leaves pre-treated with H2O; orange -
Col-0 leaves pre-treated with chitin (100 µg/ml); grey - Col-0 leaves
pre-treated with flg22 (1 µM); green - cerk1-2 leaves pre-treated
with H2O, red - cerk1-2 leaves pre-treated with
chitin (100 µg/ml) and dashed blue - cerk1-2 leaves pre-treated
with flg22 (1 µM). F. 18 hpi image ofFv/Fm for Col-0 (top right) andcerk1-2 plants pre-treated with H2O, flg22 (1 µM)
and chitin (100 µg/ml) challenged with DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .
Flg22; flg: chitin; chi: elf18; elf.
Figure 2: MAMP
pre-treatment protects Fv/Fm from
bacterial induced suppression, with the exception of chitin
pre-treatment of fls2 leaves. A. Graph quantifying changes inFv/Fm over 24 hpi with DC3000 on
Col-0 and cerk1-2 leaves. Blue line represents Col-0 leaves
pre-treated with H2O; yellow - Col-0 leaves pre-treated
with elf18 (1 µM); green - cerk1-2 leaves pre-treated with
H2O and dashed red line - cerk1-2 leaves
pre-treated with elf18 (1 µM) B. Representative visual snapshot
of Fv/Fm for a Col-0 plant (top
right) and cerk1-2 plants pre-treated with H2O
and elf18 (1 µM) at 18 hpi with DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .C. Graph quantifying changes inFv/Fm over 24 h of DC3000
infection on Col-0 and efr1 leaves. Blue represents Col-0 leaves
pre-treated with H2O; orange - Col-0 leaves pre-treated
with chitin (100 µg/ml); green - efr1 leaves pre-treated with
H2O and red - efr1 leaves pre-treated with chitin
(100 µg/ml) D. Visual snapshot ofFv/Fm for a Col-0 plant (top
right) and efr1 plants pre-treated with H2O and
chitin (100 µg/ml) at 18 hpi with DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .E. Graph quantifying changes inFv/Fm over 24 h of DC3000
infection on Col-0 and fls2 leaves. Blue represent Col-0 leaves
pre-treated with H2O; orange - Col-0 leaves pre-treated
with chitin (100 µg/ml); grey - Col-0 leaves pre-treated with flg22 (1
µM); green - fls2 leaves pre-treated with H2O;
dark blue - fls2 leaves pre-treated with chitin (100 µg/ml) and
red - fls2 leaves pre-treated with flg22 (1 µM) F. Image
of Fv/Fm for a Col-0 plant (top
right) and fls2 plants pre-treated with H2O,
chitin (100 µg/ml) and flg22 (1 µM) at 18 hpi with DC3000. Orange
represents normal Fv/Fm , whereas
yellow/green/blue represents suppressedFv/Fm .
Figure 3: DC3000 is
unable to suppress cROS in MAMP pre-treatment leaves . Col-0 leaves
treated with the non-specific species stain H2DCF-DA 5.5
hpi with DC3000hrpA and DC3000. Leaves imaged on a Zeiss 880
using excitation at 488 nm, emission window of 512–527 nm to capture
the oxidised dichlorofluorescein signal (Green). Chloroplast fluorescence
was measured at 659–679 nm (red). Scale bars showing 20 µm. A.H2O pre-treated and DC3000hrpA infectionB. H2O pre-treated and DC3000 infectionC. flg22 (1 µM) pre-treated and DC3000 infection D.elf18 (1 µM) pre-treated and DC3000 infection. Image representative of
three biological replicates.
Figure 4: Bacterial MAMP
pre-treatments provide full and partial protection on bkk1-1 andbak1-5 single mutant lines but fail to protectbak1-5/bkk1-1 lines. A. Graph quantifying changes inFv/Fm over 23 h of DC3000
infection on Col-0 and bkk1-1 leaves. Blue line represents Col-0
leaves pre-treated with H2O; grey - Col-0 leaves
pre-treated with flg22 (1 µM); yellow - Col-0 leaves pre-treated with
elf18 (1 µM); green dashed line - bkk1-1 leaves pre-treated with
H2O; dark blue - bkk1-1 leaves pre-treated with
flg22 (1 µM); red - bkk1-1 leaves pre-treated with elf18 (1 µM)B. Image, 18 hpi with DC3000, ofFv/Fm for Col-0 (top right) andbkk1-1 plants pre-treated with H2O and flg22 (1
µM). C. Image, 18 hpi with DC3000, ofFv/Fm for Col-0 (top right) andbkk1-1 plants pre-treated with H2O and elf18 (1
µM). Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .D. Graph quantifying changes inFv/Fm over 23 hpi with DC3000 on
Col-0 and bak1-5 leaves. Blue represents Col-0 leaves pre-treated
with H2O; grey - Col-0 leaves pre-treated with flg22 (1
µM); yellow - Col-0 leaves pre-treated with elf18 (1 µM); green -bak1-5 leaves pre-treated with H2O; dark blue -bak1-5 leaves pre-treated with flg22 (1 µM) and red corresponds
to bak1-5 leaves pre-treated with elf18 (1 µM) E. Image
at 18 hpi with DC3000, of Fv/Fmfor Col-0 (top right), bak1-5 (top left) or bak1-5/bkk1-1(bottom), plants pre-treated with H2O and flg22 (1 µM).F. Image, 18 hpi with DC3000, ofFv/Fm for Col-0 (top right),bak1-5 (bottom) or bak1-5/bkk1-1 (top left), plants
pre-treated with H2O and elf18 (1 µM) at 18 hpi with
DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .G. Quantitative changes inFv/Fm over 23 hpi with DC3000 on
Col-0 and bak1-5/bkk1-1 leaves. Blue represents Col-0 leaves
pre-treated with H2O; grey - Col-0 leaves pre-treated
with flg22 (1 µM); yellow - Col-0 leaves pre-treated with elf18 (1 µM);
green - bak1-5/bkk1-1 leaves pre-treated with
H2O; dark blue - bak1-5/bkk1-1 leaves pre-treated
with flg22 (1 µM) and red represents bak1-5/bkk1-1 leaves
pre-treated with elf18 (1 µM).
Figure 5: DAMP
pre-treatment restricts suppression ofFv/Fm following bacterial
challenge. A. Graph quantifying changes inFv/Fm over 24 hpi following
DC3000 infection of Col-0. Blue represents leaves pre-treated with
H2O; orange - pre-treated with Pep1 (1 µM); dashed grey
- pre-treated with Pep2 (1 µM) and yellow represents pre-treated with
Pep3 (1 µM). B. Image ofFv/Fm in Col-0 plants pre-treated
with H2O, Pep1 (1 µM), Pep2 (1 µM) or Pep3 (1 µM) at 18
hpi with DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .C. Graph quantifying changes inFv/Fm over 24 hpi with DC3000 on
Col-0 and pepR1-1x1-2 leaves. Blue represents Col-0 leaves
pre-treated with H2O; orange - Col-0 pre-treated with
pep1 (1 µM); yellow - Col-0 pre-treated with pep3 (1 µM); red -pepR1-1x1-2 pre-treated with H2O; dark blue -pepR1-1x1-2 pre-treated with pep1 (1 µM) and green representspepR1-1x1-2 leaves pre-treated with pep3 (1 µM). D.Image of Fv/Fm for Col-0 (right)
and pepR1-1x1-2 pre-treated with H2O, Pep1 (1
µM), and Pep3 (1 µM) 18 hpi with DC3000. Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .E. Graph quantifying changes inFv/Fm over 24 hpi with DC3000 on
Col-0 and pepR1-1x1-2 leaves. Blue represents Col-0 leaves
pre-treated with H2O; grey - Col-0 leaves pre-treated
with flg22 (1 µM); red - pepR1-1x1-2 leaves pre-treated with
H2O and dark blue - pepR1-1x1-2 leaves
pre-treated with flg22 (1 µM). F. Representative image, 18 hpi
with DC3000, of Fv/Fm for Col-0
(right) and pepR1-1x1-2 plants pre-treated with
H2O and flg22 (1 µM). Orange represents normalFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .
Figure 6: High light
enhances bacterial suppression ofFv/Fm. A. Graph quantifying
changes in Fv/Fm over 24 hpi of
DC3000 (blue line) and DC3000hrpA (orange line) infection on
Col-0 leaves under normal light (NL) (120 µmol
m-2s-1). B. Image ofFv/Fm at 23 hpi of Col-0 plants
with DC3000 and DC3000hrpA under NL (120 µmol
m-2s-1). Orange represents
the expected Fv/Fm , whereas
yellow/green/blue represents suppressedFv/Fm . C. Graph
quantifying changes in Fv/Fm over
26.5 hpi of DC3000 (blue line) and DC3000hrpA (orange line)
infection on Col-0 leaves under high light (HL) (650 µmol
m-2s-1). D. Image ofFv/Fm at 22.75 hpi of Col-0
plants with DC3000 and DC3000hrpA under HL (650 µmol
m-2s-1). Unlabelled leaves
are not infiltrated. Orange represents expectedFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .E. Graph quantifying changes inFv/Fm over 26.5 hpi of DC3000 on
Col-0 under high light (HL) (650 µmol
m-2s-1). Blue represents Col-0
leaves pre-treated with H2O; grey - Col-0 leaves
pre-treated with flg22 (1 µM) and the yellow line represents Col-0
leaves pre-treated with elf18 (1 µM). F. Image ofFv/Fm for Col-0 plants
pre-treated with H2O, flg22 (1 µM) and elf18 (1 µM) at
22.75 hpi with DC3000 under HL (650 µmol
m-2s-1). Orange represents
expected Fv/Fm , whereas
yellow/green/blue represents suppressedFv/Fm . G. Graph
quantifying changes in Fv/Fm over
26.5 hpi of Col-0 and bak1-5/bkk1-1 leaves with DC3000 under high
light (HL) (650 µmol m-2s-1). Blue
represents Col-0 and red bak1-5/bkk1-1 leaves H. Image
of Fv/Fm 22.75 hpi with DC3000 on
Col-0 plant (right) or bak1-5/bkk1-1 plants under HL (650 µmol
m-2s-1). Orange represents
expected Fv/Fm , whereas
yellow/green/blue represents suppressedFv/Fm .
Figure 7: High light
renders Col-0 and bak1-5/bkk1-1 plants more susceptible to
bacterial infection. Bacterial growth of DC3000 on Col-0, fls2and bak1-5/bkk1-1 plants under normal light (NL; blue; 120 µmol
m-2s-1) and high light (HL; red; 450
µmol m-2s-1). Error bars, mean ± SE
(n=6), student t-test determined statistical significance of P
< 0.0001 for NL Col-0 vs fls2 and Col-0 vsbak1-5/bkk1-1 (not shown on graph), HL Col-0 vsbak1-5/bkk1-1, Col-0 NL vs HL, bak1-5/bkk1-1 NL vs HL.
There was no significant difference between HL Col-0 vs fls2 andfls2 NL vs HL. Representative of three biological replicates.
Figure 8: Exogeneous ABA
synergistically or antagonistically alters pathogen induced ABA
suppression of Fv/Fm in a
concentration dependent manner. A. Graph quantifying changes inFv/Fm over 24 hpi following
DC3000 or DC3000hrpA infection of Col-0, aao3 andabi1/abi2/hab1 leaves. Blue represents Col-0 leaves infiltrated
with DC3000; red - Col-0 leaves infiltrated with DC3000hrpA ; grey
- aao3 leaves infiltrated with DC3000; yellow - aao3leaves infiltrated with DC3000hrpA ; dark blue -abi1/abi2/hab1 leaves infiltrated with DC3000 and green
corresponds to abi1/abi2/hab1 leaves infiltrated with
DC3000hrpA . B. Image ofFv/Fm of Col-0, aao3 andabi1/abi2/hab1 plants 18 hpi with DC3000 or DC3000hrpA .
Orange represents normal Fv/Fm readout, whereas yellow/green/blue represents suppressedFv/Fm . C. Bacterial
growth of DC3000 on Col-0, aao3 or abi1/abi2/hab1 plants
under normal light (NL; 120 µmol
m-2s-1; blue) or high light (HL; 450
µmol m-2s-1; orange) conditions.
Error bars, mean ± SE (n=6) student t-test determined statistical
significance of P < 0.0001 for Col-0 NL vs HL (shown),
statistical significance of P < 0.001 for aao3 NL vs HL
and statistical significance of P < 0.005 for HL Col-0 vsabi1/abi2/hab1 . Representative of three replicated experiments.D. Graph quantifying
changes in Fv/Fm 24 hpi with
DC3000 on Col-0 leaves in the presence of ABA under normal light (NL;
120 µmol m-2s-1). Blue - Col-0
leaves infiltrated with DC3000 and orange - Col-0 leaves co-infiltrated
with DC3000 + 10 µM ABA. E. Image ofFv/Fm of Col-0, plants 18 hpi
infiltrated with DC3000 and co-infiltrated with DC3000 and 10 µM ABA
under NL. Orange represents expectedFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .F. Graph quantifying changes inFv/Fm up to 24 hpi with DC3000 of
Col-0 leaves in the presence of increasing concentrations of ABA under
high light (HL; 650 µmol m-2s-1).
Blue represents Col-0 leaves infiltrated with DC3000; orange - Col-0
leaves co-infiltrated with DC3000 + 10 µM ABA and grey corresponds to
Col-0 leaves co-infiltrated with DC3000 + 100 µM ABA. E. Image,
19.5 hpi, of Fv/Fm of Col-0
infiltrated with DC3000, co-infiltrated with DC3000 and 10 or 100 µM ABA
under HL. Orange represents expectedFv/Fm , whereas yellow/green/blue
represents suppressed Fv/Fm .
Figure 9: Schematic
overview of findings from study. Black arrows show pathways to normalFv/Fm while red arrows show
pathways to suppressed Fv/Fm or
increased bacterial growth. A. MAMP pre-treatment followed by
DC3000 infection on receptor mutant plants. fls2 leaves
pre-treated with elf18 maintain normalFv/Fm while fls2 leaves
pre-treated with chitin, Pep1 or 2 show suppressedFv/Fm . efr1 leaves
pre-treated with flg22 or chitin maintain normalFv/Fm . cerk1-2 leaves
pre-treated with flg22 or elf18 maintain normalFv/Fm . PepR1-1x2-1 leaves
with flg22 maintain normal Fv/Fm .B. MAMP pre-treatment followed by DC3000 infection on MTI
co-receptor mutant plants. bak1-5 leaves pre-treated with flg22
or elf18 maintain normal Fv/Fmwhile bak1-5 leaves pre-treated with chitin show suppressedFv/Fm . bkk1-1 leaves
pre-treated with flg22, elf18 or chitin maintain normalFv/Fm . bak1-5/bkk1-1leaves pre-treated with flg22, elf18, chitin, Pep1 or 2 show suppressedFv/Fm . Under high light (HL)
conditions (dashed red line) bak1-5/bkk1-1 leaves show an
increased suppression of Fv/Fm(thick, red dashed arrow) and increased bacterial growth compared to
normal light (NL) conditions. C. Chlorophyll fluorescence and
bacterial growth are altered under different light conditions. Under
normal light (NL; 120 µmol m-2s-1)
conditions DC3000hrpA infected leaves maintain normalFv/Fm , while DC3000 infected
leaves show suppressed Fv/Fm .
Pre-treatment of Col-0 leaves with flg22 or elf18 under NL results in
normal Fv/Fm . Under high light
(HL; 650 µmol m-2s-1)
DC3000hrpA , DC3000 and flg22 or elf18 pre-treated DC3000 infected
leaves all show suppressed Fv/Fmand DC3000 infected leaves show an increase in bacterial growth.D. Chlorophyll fluorescence is reduced during high light and ABA
treatment. Under normal light (NL; 120 µmol
m-2s-1) conditions DC3000 infected
leaves and leaves co-infiltrated with DC3000 + 10 µM show suppressedFv/Fm . Under high light (HL; 650
µmol m-2s-1) leaves infected with
DC3000, leaves co-infiltrated with DC3000 + 10 µM and leaves
co-infiltrated with DC3000 + 100 µM all showed suppressedFv/Fm . Created with
BioRender.com.