Journal: bioRxiv

Article Title: Septins buffer actomyosin forces to protect the nucleus from genotoxic mechanical stress

doi: 10.64898/2026.01.21.700789

Figure Lengend Snippet: a , Sagittal view of SEPT9_i1 (green) and the nucleus (DAPI, blue) in a 3D volume region of a U2OS cell confined in an 8 mm-wide pore. Scale bar, 2 μm. b, Top-down and sagittal side views of a confined U2OS subcellular region after staining for SEPT7 (green), SEPT9_i1 (magenta) and the nucleus (DAPI, blue). Images were 3D reconstructed, and volume rendered. Scale bars, 1 μm (top-down view) and 2 μm (sideview). c-d, Single optical sections of a confined U2OS cell region taken from medial (c) and basal (d) depths after staining for SEPT7 (green) and SEPT9_i1 (magenta). Scale bar, 1 μm. e, Sagittal sideviews of the nucleus (DAPI, blue), F-actin (phalloidin, grayscale), SEPT9_i1 (green) and vimentin (magenta) in a 3D volume region of a U2OS cell confined in an 8 mm-wide pore. The view shown in the top row of images is rotated 180 degrees in the bottom row. The perinuclear vimentin basket is outlined with a yellow dashed line. Scale bars, 2 μm. All U2OS cell images were acquired with super-resolution SoRa SDCM 12 h after plating on 8 μm-wide pores.

Article Snippet: The mammalian cell lines U2OS (ATCC HTB-96) and MDA-MB-231 (ATCC HTB-26) were maintained in DMEM High Glucose medium (Sigma-Aldrich-07777).

Techniques: Staining

Journal: bioRxiv

Article Title: Septins buffer actomyosin forces to protect the nucleus from genotoxic mechanical stress

doi: 10.64898/2026.01.21.700789

Figure Lengend Snippet: a , Top-down (top) and oblique angle (middle, bottom) views of still frames from time-lapse 3D SoRa SDCM imaging of LAP2β-AcGFP1 (green) and SPY555_FastAct_X (magenta) in the U2OS cell region confined in a Matrigel/laminin-filled 8 μm-wide pore. Images were rendered and reconstructed in 3D for each time point. Angled side views are more zoomed in on the nuclear envelope, which appears to surround the pore. Nuclear envelope creases and folds (arrows) are seen in the 60 and 120 minute time frames. Note that the nuclear envelope preserves its continuity in the 120 minute timeframe, but the front side becomes dim due to higher signal intensity in the creased regions of the 3D-rendered image. Scale bars, 2 μm. b, Time-lapse frames of a single optical slice from SoRa SDCM imaging of a U2OS cell region confined in a Matrigel/laminin-filled 8 μm-wide pore. U2OS cells were transfected with GFP-SEPT9_i1 (green) and labeled live with SPY650_FastAct_X (magents). White arrows point to actin that colocalizes with GFP-SEPT9_i1, and enlarges overtime. Blue arrows point to actoseptin that appears in frame de novo and remains spatially stable overtime. Scale bars, 2 μm. c, Still frames show side views of 3D volume images from time-lapse 3D SoRa SDCM imaging of GFP-SEPT9_i1 (green) and SPY650_FastAct_X (magenta) in a U2OS cell region confined in a Matrigel/laminin-filled 8 μm-wide pore. Yellow arrowheads point to short-lived actoseptin cables. White arrows point to longer lived actoseptin cables which become brighter and thicker. Blue arrows point to de novo generation of actoseptin cables that grow longitudinally and laterally. Scale bar, 1 μm.

Article Snippet: The mammalian cell lines U2OS (ATCC HTB-96) and MDA-MB-231 (ATCC HTB-26) were maintained in DMEM High Glucose medium (Sigma-Aldrich-07777).

Techniques: Imaging, Transfection, Labeling

Journal: bioRxiv

Article Title: Septins buffer actomyosin forces to protect the nucleus from genotoxic mechanical stress

doi: 10.64898/2026.01.21.700789

Figure Lengend Snippet: a , Western blots of lysates of parental U2OS and cell clones after selection for stable expression of SEPT9_i1 targeting sgRNA relative. Cell lysates were blotted with antibodies against the SEPT9_i1 isoform and SEPT7. b, Wide-field microscopy images of U2OS cells that stably express control and SEPT9_i1 sgRNAs after staining for F-actin (phalloidin, magenta) and the SEPT9_i1 isoform (green). Insets show outlined regions in higher magnification. Scale bars, 20 μm. c-e, Sagittal side views of 3D rendered images of the confined regions of control and SEPT9_i1-depleted U2OS cells in 8 μm (c), 5 μm (d) and 3 μm (e) wide pores. Cells were stained with phalloidin (F-actin, magenta) and antibody against zyxin (grayscale). Nuclear areas are outlined with dashed yellow line. Outlined regions with zyxin-decorated actin cables are shown in higher magnification. Scale bars, 2 μm (c, d) and 1 μm (e).

Article Snippet: The mammalian cell lines U2OS (ATCC HTB-96) and MDA-MB-231 (ATCC HTB-26) were maintained in DMEM High Glucose medium (Sigma-Aldrich-07777).

Techniques: Western Blot, Clone Assay, Selection, Expressing, Microscopy, Stable Transfection, Control, Staining

Journal: bioRxiv

Article Title: EARLY FLOWERING 3 (ELF3): a novel role in integrating environmental stimuli with root stem cell niche maintenance

doi: 10.64898/2026.01.12.699078

Figure Lengend Snippet: a-d: Subcellular localization of mV-tagged PLT3, ELF3, PIF3, and PIF4 in HEp-2 cells. e-e’’: ELF3-mV (yellow) localizes to cytoplasmic condensates when co-expressed with PLT3-mRb (red), which forms nuclear condensates. f-i’’: ELF3-mV (yellow) and PLT3-mV colocalize with PIF3-Cer (cyan) and PIF4-Cer (cyan) in the nucleus within condensates. j-k’’’: FP-tagged ELF3 (yellow) and PLT3 (red) colocalize in the nucleus with PIF3-Cer and PIF4-Cer. Scale bars represent 5 µm. mV= mVenus; mRb= mRuby2; Cer= Cerulean.

Article Snippet: Therefore, we used mammalian Human epithelial cells HEp-2 (epithelial larynx carcinoma, ATCC-CCL-23) as a non-plant orthogonal system for transient protein expression.

Techniques: