Fig. 1: Dense regions of actin-binding protein contain glycolytic enzymes upon hyperosmotic stress.
From: TPM4 condensates glycolytic enzymes and facilitates actin reorganization under hyperosmotic stress
a Representative images of MDA-MB-231 cells expressing LifeAct-EGFP before (isosmotic) and after (hyperosmotic) 100 mM sorbitol treatment for 1 h. Scale bar, 20 μm. b Top: barbed end assay showing the distribution of rhodamine-actin in MDA-MB-231 cells before (isosmotic) and after (hyperosmotic) 100 mM sorbitol treatment for 3 min. Actin filaments are labeled by phalloidin. Scale bar, 20 μm. Bottom: quantification of barbed end intensity in MDA-MB-231 cells before (isosmotic) and after (hyperosmotic) 100 mM sorbitol treatment for 3 min. n = 34; error bar: mean with SEM; ****P < 0.0001 by unpaired t-test. c Representative images of MDA-MB-231 cells expressing PDLIM1-AcGFP or TPM4-AcGFP before (isosmotic) and after (hyperosmotic) 100 mM sorbitol treatment for 3 min. Scale bars, 20 μm. d Left: Venn diagram illustrating the identified proteins by TurboID proximity labeling/mass spectrometry using ArgBP2, PDLIM1, α-actinin1 and TPM4 fused with TurboID. Right: enrichment analysis by Metascape showing top enriched signaling pathways. e PLA assay showing the interaction between TPM4-AcGFP and PFKM in MDA-MB-231 cells under hyperosmotic condition (100 mM sorbitol for 3 min). Scale bar, 20 μm. f Left: schematic diagram of split-GFP system expressing TPM4-GFP1–10 and PFKM-GFP11. Right: representative images of MDA-MB-231 cells expressing split-GFP constructs before (isosmotic) and after (hyperosmotic) 100 mM sorbitol treatment for 3 min. Scale bar, 20 μm. g Representative images of PFKM (yellow) and phalloidin (magenta) immunofluorescence staining in MDA-MB-231 cells expressing TPM4-AcGFP under hyperosmotic condition (100 mM sorbitol for 3 min). Scale bar, 20 μm.
