PostnMCM PostnMCM

Smad2fl/fl PostnMCM

Smad3fl/fl

PostnMCM

Smad2/3fl/fl PostnMCM

Tgfbr1/2fl/fl

Tcf21MCM Tcf21MCM Smad3fl/fl Tcf21MCM Smad2/3fl/fl Tcf21MCM Tgfbr1/2fl/fl αMHCMCM

αMHCMCM Smad2/3fl/fl

1.0 mm

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TAC

TA

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TAC

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PostnMCM PostnMCM Smad2fl/fl PostnMCM Smad3fl/fl PostnMCM Smad2/3fl/fl

TGFβ DTG background

12 m

onth

s

Supplemental Figure 1. Whole heart sections to accompany microscopic histological images in Figure 3 and 6. (A-D) Masson’s trichrome-stained histological whole heart images from the indicated genotypes of mice. The number of mice used in each of the experimental cohorts is discussed in the primary figures 3 and 6. Scale bar 1 mm. Fibrotic areas stain blue.

PostnMCM PostnMCM Smad2fl/fl

PostnMCM Smad3fl/fl

PostnMCM Smad2/3fl/fl

PostnMCM Tgfbr1/2fl/fl

100 µm

Pic

ro S

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100 µm

Supplemental Figure 2. Fibroblast-specific deletion of canonical TGFβ signaling does not modulate collagen maturation after TAC injury. Representative Picro-sirius red-stained histological pictures (bottom) and their corresponding polarized microscopy to show collagen complexity (top) in hearts from the indicated genotypes of mice after 12 weeks of TAC injury and continuous tamoxifen treatment. n=5 mice in each group. The data again show a reduction in cardiac fibrosis with PostnMCM-mediated deletion of Smad3, Smad2/3 orTgfbr1/2 (Picro-sirius red staining). However, there was no apparent differences in collagen maturation in the hearts as analyzed with polarized light (orange-red birifringence) across the gentoypes. Scale bar 100 μm.

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A B C

Supplemental Figure 3. Smad3 regulates ECM gene expression. (A-C) Adult primary heart fibroblasts were isolated from Smad2-loxP, Smad3-loxP and Smad2/3-loxP-targeted mice and infected with Adβgal or AdCre (KO samples). Seventy-two hrs after infection cells were treated with vehicle or 10 ng/ml of TGFβ for 24 hours. The data are real-time PCR results showing the expression levels of collagen 1a1, collagen 3a1 and periostin (Postn). n=3 separate experiments. *P<0.05 versus Wt+TGFβ; #P<0.05 versus Wt. P values represent one-way ANOVA with post-hoc Tukey HSD.

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PostnMCM: + + + + + + PostnMCM: + + + + + +

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)

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E/e

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PostnMCM:

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TAC (4w) Sham

C D

Supplemental Figure 4: Cardiac functional assessment with fibroblast-specific Smad2/3 and Tgfbr1/2 deletion. (A) Echocardiographic assessment of left ventricular fractional shortening (FS) percentage in the indicated genotypes of mice after 12 weeks of TAC injury. *P < 0.05 versus PostnMCM/+ Sham; #P<0.05 versus PostnMCM TAC. P values were calculated with ANOVA and Tukey's post-test. (B) Ratios of heart-weight to body-weight (HW/BW) in mice after 12 weeks of TAC. n=7-9 in each group. *P < 0.05 versus PostnMCM/+ Sham; #P<0.05 versus PostnMCM TAC. P values were calculated with ANOVA and Tukey's post-test. (C) Myocardial wall compliance assessed by echocardiographic strain (longitudinal speckle-tracking analysis) presented as a percentage of peak, 4 weeks post-TAC. The data show a trend for less wall compliance (more disease) in the Smad2/3 double-deleted mouse hearts but not Tgfbr1/2 double nulls. (N=3-5). (D) Diastolic function was assessed by tissue Doppler echocardiography as the E/e’ ratio that measures mitral valve inflow maximum velocity (E-wave) to posterior wall maximum tissue Doppler velocity (e’) ratio in the indicated genotypes of mice after 4 weeks of TAC (n=3-4). Statistical comparison by t-Test between sham and WT or Smad2/3 double nulls was significant but not when compared with Tgfbr1/2 double null. However, by one-way ANOVA the data only showed a trend and did not achieve significance. (N=3-5 mice per group).

* *

PostnMCM R26eGFP

PostnMCM Smad2/3fl/fl R26eGFP

DAPI αSMA eGFP αSMA DAPI eGFP DAPI eGFP αSMA

DAPI αSMA eGFP αSMA DAPI eGFP DAPI eGFP αSMA

Supplemental Figure 5. Additional images with more fluorescent imaging channels to support Figure 4D. Representative immunohistochemistry on cryosections from a different plane of sectioning from the heart compared with what is shown in Figure 4D. The data show eGFP-labeled (green) fibroblasts along with αSMA (red) positive cells from hearts of the indicated genotypes of mice after 4 weeks of TAC. DAPI staining shows nuclei (blue). The white arrows show eGFP+ fibroblasts, which are αSMA+ in hearts from control PostnMCM R26eGFP mice but αSMA negative in hearts from PostnMCM Smad2/3fl/fl R26eGFP mice. The Yellow arrow shows αSMA fibroblasts that are not eGFP+ (Representative images from n=4 hearts/mice in each of the 2 groups). Scale bars are 10 μm.

WT

Sm

ad2/

3 K

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EGFP, CD31, DAPI, EdU

50 µm 100 µm

Supplemental Figure 6. Fibroblast-specific deletion of Smad2/3 does not affect endothelial cell proliferation after TAC injury, although fibroblast proliferation is dramatically reduced. Immunohistochemical heart images from wild-type (WT) and Smad2/3 activated fibroblast-specific knockout (KO) mice (with PostnMCM allele) subjected to TAC injury as described in Figure 5D and E. Mice were injected with EdU 4 and 24 hrs before harvest. EGFP+ fibroblasts are shown in green and CD31+ endothelial cells are in red while EdU proliferation marking is in white and nuclei are blue with DAPI staining. The inset boxes correspond to high magnification images shown on the right (only the white and red channels). n=3 mice in each group. The data show that fibroblasts mostly lack EdU staining with Smad2/3 deletion compared with WT control, although the same relative rate of endothelial cell EdU positivity between genotypes is observed. Size of the scale bars is shown in the panels.

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WT Smad2fl/fl Smad3fl/fl Smad2/3fl/fl Tgfbr1/2fl/fl Cre: - + - + - + - + - + - + - + - + - + - +

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cent

dea

d Untreated

Staurosporine

Supplemental Figure 7. Fibroblast-specific deletion of canonical TGFβ signaling does not modulate staurosprine induced apoptosis of fibroblasts. Wild-type (WT), Smad2/3-loxP and Tgfbr1/2-loxP primary skin fibroblasts were infected with Adβgal or AdCre for 96 hours and then treated with vehicle (DMSO) or 200 nM staurosporine for 36 hours. Dead cells (which have permeabilized membranes) were labeled with the Muse Count & Viability assay and quantitated using a Muse Cell Analyzer. Treatments were performed in duplicate and averaged from two independent experiments. Loss of any of the canonical TGFβ signaling genes from the genotypes of primary skin fibroblasts analyzed here had no effect on levels of staurosporine-induced apoptosis.