Septins regulate junctional integrity of endothelial monolayers

Endothelial cell junctions control permeability and tissue homeostasis. Prior research has shown that VE-cadherin and actin are central to junctional structure. However, the role of septins in these junctions remained unclear. This gap motivated the investigation into how septins might influence junctional dynamics. No prior work had resolved whether septins contribute to junctional stability. The study aimed to clarify if septins function at endothelial cell junctions. The research focused on whether septins interact with VE-cadherin or actin at junctions. The goal was to determine if septins affect junctional integrity in endothelial monolayers.

The aim was to explore the role of septins in endothelial junctions. The specific problem was to determine if septins influence junctional structure and function. The motivation came from the lack of knowledge about septin localization at endothelial junctions. The researchers wanted to test if septins interact with VE-cadherin or actin. They also sought to assess whether septins affect junctional morphology. The study aimed to evaluate if septin depletion impacts junctional integrity. The goal was to determine how septins might support actin-rich protrusions. The purpose was to clarify the functional role of septins in endothelial junctions.

The study used endothelial monolayers to examine junctional dynamics. Researchers observed cell junctions using live-cell imaging techniques. They labeled VE-cadherin and F-actin to track their localization. Septin localization was visualized using fluorescent markers. The team analyzed junctional morphology in control and septin-depleted cells. They used transendothelial electrical resistance to measure barrier function. Immune cell transmigration was assessed to evaluate junctional permeability. The approach combined imaging, biochemical assays, and functional tests.

Septins localized at cell junctions in distinct patterns from VE-cadherin and F-actin. They formed curved and scallop-shaped structures at regions of positive curvature. Septin depletion caused VE-cadherin junctions to become broader and less defined. Membrane ruffling increased in septin-depleted cells compared to controls. Transendothelial electrical resistance decreased in septin-depleted monolayers. Immune cell transmigration increased after septin depletion. Junctional remodeling was evident in live-cell videos of septin-depleted cells. The findings suggest septins support junctional integrity in endothelial monolayers.

The authors propose that septins are important for junctional integrity in endothelial monolayers. They suggest that septins function at regions of positive membrane curvature. The findings indicate that septins support actin-rich protrusions at junctions. The study implies that septins may promote cadherin-based junctions. The results suggest that septin depletion disrupts VE-cadherin junction morphology. The authors conclude that septins contribute to junctional stability. The data support the idea that septins are cytoskeletal elements at junctions. The study highlights the role of septins in endothelial barrier function.