Interplay between Solo and keratin filaments is crucial for mechanical force–induced stress fiber reinforcement

Supplemental Materials

This article contains the following supporting material:

  • Supplemental Materials
  • Movie 1 - Supplemental Movie 1. Time-lapse observation of tensional force-induced stress fiber formation in MDCK/YFP-Lifeact cells treated with control or Solo-targeting siRNAs. Cells were cultured on FN-coated silicone membranes, and tensile force was applied by inserting a glass needle into the silicone membrane adjacent to the cell and sliding it away from the cell. Time-lapse fluorescence analysis of YFP-Lifeact was performed at 37°C, using an LSM 710 confocal microscope equipped with an EC Plan N 40? oil objective lens (NA 1.3). A white box indicates the area in which stress fibers were generated or reinforced after force application. Frames were acquired every 5 s for 5.5 min and are displayed at 15 frames/s. Scale bars, 20 μm. Related to Figure 5, B-D.
  • Movie 3 - Supplemental Movie 3. Time-lapse observation of tensional force-induced stress fiber formation in MDCK/YFP-Lifeact cells that are expressed with Solo or its mutants. Cells were cultured on FN-coated silicone membranes on glass-bottom dish, and tensile force was applied as in Supplemental Movie 1. White boxes indicate the area in which stress fibers were generated or reinforced after force application. Time-lapse fluorescence analysis of YFP-Lifeact was performed using the same settings as in Supplemental Movie 1. Frames were acquired every 5 s for 5.5 min and are displayed at 15 frames/s. Scale bars, 20 μm. Related to Figure 5F and Supplemental Figure S4B.
  • Movie 5 - Supplemental Movie 5. Time-lapse observation of tensional force-induced stress fiber formation in MDCK/YFP-Lifeact cells treated with control or K18-targeting siRNAs. Cells were cultured on FN-coated silicone membranes, and tensile force was applied as in Supplemental Movie 1. A white box indicates the area in which stress fibers were generated or reinforced after force application. Time-lapse fluorescence analysis of YFP-Lifeact was performed using the same settings as in Supplemental Movie 1. Frames were acquired every 5 s for 5.5 min and are displayed at 15 frames/s. Scale bars, 20 μm. Related to Figure 6E and Supplemental Figure S5.
  • Movie 4 - Supplemental Movie 4. Time-lapse observation of the localization of CFP-Solo-WT in MDCK/YFP-Lifeact cells subjected to tensional force application. Cells were cultured on FN-coated silicone membranes on glass-bottom dish, and tensile force was applied as in Supplemental Movie 1. Time-lapse analyses of CFP fluorescence (top) and bright-field images (bottom) were performed using the same settings as in Supplemental Movie 1. Frames were acquired every 5 s for 5.5 min and are displayed at 15 frames/s. Scale bars, 20 μm. Related to Supplemental Figure S4B, CFP-Solo-WT.
  • Movie 2 - Supplemental Movie 2. Time-lapse observation of tensional force-induced stress fiber formation in MDCK/YFP-Lifeact cells treated with Solo-targeting siRNAs, followed by transfection with CFP-Solo-WT, Tom20(1-33)-CFP-Solo, or CFP-Solo(1058-1519). Cells were cultured on FN-coated silicone membranes on glass-bottom dish, and tensile force was applied as in Supplemental Movie 1. A white box indicates the area in which stress fibers were generated or reinforced after force application. Time-lapse fluorescence analysis of YFP-Lifeact was performed using the same settings as in Supplemental Movie 1. Frames were acquired every 5 s for 5.5 min and are displayed at 15 frames/s. Scale bars, 20 μm. Related to Figure 5E and Supplemental Figure S3C.