# Title of Dataset: Raw_Data_Fig.3A_bis.xlsx Brief summary of dataset contents: Raw data corresponding to Figure 3A. Quantification of the duration of mitosis phases in HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with control siRNA or siRNA targetting SUN2. These experiments were conducted to evaluate the impact of SUN2 depletion on mitosis progression. Mitosis duration was calculated as the time from the first image showing the Nuclear Envelope Breakdown (NEBD) to the first image showing nuclear envelope reformation. Prometaphase duration was calculated as the time from the first image showing NEBD to the last image showing all chromosomes congression at the metaphase plate. Metaphase was calculated as the time from chromosomes congression at the metaphase plate to the image just before chromosomes segregation. Anaphase was calculated as the time from the first image showing chromosomes segregation to the first image showing nuclear envelope reformation. Data were collected from 3 independent experiments (biological replicates) using using spinning disk confocal microscope Andromeda TILL-FEI fitted with a Plan-Apochromat 20x/0.75, WD 610 objective and coupled to a EMCCD camera iXon 897. The microscope was equipped with a temperature- and CO2-controlled incubator box (37°C and 5% CO2) and images were taken every 2.5 minutes for 15 hours minimum. Acquisition was performed with LA, FEI software and analysis with OA, FEI software and with ImageJ. ## Description of the Data and file structure Table content: biological replicate (from n=1 to n=3), condition name (control siRNA or SUN2 siRNA), first frame number and last frame number for each phase (prophase, metaphase and anaphase), number of frames for each phase (prophase, metaphase and anaphase) and duration (min) for each phase, calculated as number of frames * 2.5 (2.5=frame rate: one frame every 2.5 min.) Following files are provided as Supplemental Information # Title of Dataset: Video_siControl_1 Brief summary of dataset contents: Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with control siRNA using spinning disk confocal microscope Andromeda TILL-FEI fitted with a Plan-Apochromat 20x/0.75, WD 610 objective and coupled to a EMCCD camera iXon 897. The microscope was equipped with a temperature- and CO2-controlled incubator box (37°C and 5% CO2) and images were taken every 2.5 minutes for 15 hours minimum. Acquisition was performed with LA, FEI software. ## Description of the Data and file structure Avi Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with control siRNA. One image every 2.5 min # Title of Dataset: Video_siControl_2 Brief summary of dataset contents: Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with control siRNA using spinning disk confocal microscope Andromeda TILL-FEI fitted with a Plan-Apochromat 20x/0.75, WD 610 objective and coupled to a EMCCD camera iXon 897. The microscope was equipped with a temperature- and CO2-controlled incubator box (37°C and 5% CO2) and images were taken every 2.5 minutes for 15 hours minimum. Acquisition was performed with LA, FEI software. ## Description of the Data and file structure Avi Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with control siRNA. One image every 2.5 min # Title of Dataset: Video_siSUN2_1 Brief summary of dataset contents: Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with SUN2 siRNA using spinning disk confocal microscope Andromeda TILL-FEI fitted with a Plan-Apochromat 20x/0.75, WD 610 objective and coupled to a EMCCD camera iXon 897. The microscope was equipped with a temperature- and CO2-controlled incubator box (37°C and 5% CO2) and images were taken every 2.5 minutes for 15 hours minimum. Acquisition was performed with LA, FEI software. ## Description of the Data and file structure Avi Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with SUN2 siRNA. One image every 2.5 min # Title of Dataset: Video_siSUN2_2 Brief summary of dataset contents: Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with control siRNA using spinning disk confocal microscope Andromeda TILL-FEI fitted with a Plan-Apochromat 20x/0.75, WD 610 objective and coupled to a EMCCD camera iXon 897. The microscope was equipped with a temperature- and CO2-controlled incubator box (37°C and 5% CO2) and images were taken every 2.5 minutes for 15 hours minimum. Acquisition was performed with LA, FEI software. ## Description of the Data and file structure Avi Video of HeLa Kyoto EGFP-LaminA/H2B-mCherry cells transfected with SUN2 siRNA. One image every 2.5 min # Title of Dataset: Western_Blot_1_GAPDH Brief summary of dataset contents: A7R5 were cultured on 1 or 50 kPa matrix for 6h, 24h and 5 days. Cells were lysed in Laemli and processed for western blot (SUN2 and GAPDH) to compare SUN2 expression. ## Description of the Data and file structure Scan of Uncropped gel blotted for GAPDH. Conditions from left: 1kPa 6hours, 50 kPa 6hours, 1kPa 24hours, 50 kPa 24 hours, 1 kPa 5 days, 50 kPa 5 days. # Title of Dataset: Western_Blot_1_SUN2 Brief summary of dataset contents: A7R5 were cultured on 1 or 50 kPa matrix for 6h, 24h and 5 days. Cells were lysed in Laemli and processed for western blot (SUN2 and GAPDH) to compare SUN2 expression. ## Description of the Data and file structure Scan of Uncropped gel blotted for SUN2. Conditions from left: 1kPa 6hours, 50 kPa 6hours, 1kPa 24hours, 50 kPa 24 hours, 1 kPa 5 days, 50 kPa 5 days. # Title of Dataset: Western_Blot_2_GAPDH Brief summary of dataset contents: A7R5 were cultured on 1 or 50 kPa matrix for 6h, 24h and 5 days. Cells were lysed in Laemli and processed for western blot (SUN2 and GAPDH) to compare SUN2 expression. ## Description of the Data and file structure Scan of Uncropped gel blotted for GAPDH. Conditions from left: 1kPa 6hours, 50 kPa 6hours, 1kPa 24hours, 50 kPa 24 hours, 1 kPa 5 days, 50 kPa 5 days. # Title of Dataset: Western_Blot_2_SUN2 Brief summary of dataset contents: A7R5 were cultured on 1 or 50 kPa matrix for 6h, 24h and 5 days. Cells were lysed in Laemli and processed for western blot (SUN2 and GAPDH) to compare SUN2 expression. ## Description of the Data and file structure Scan of Uncropped gel blotted for SUN2. Conditions from left: 1kPa 6hours, 50 kPa 6hours, 1kPa 24hours, 50 kPa 24 hours, 1 kPa 5 days, 50 kPa 5 days.