Department of Medicine, University of Arizona, Tucson, AZ, USA.
Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA.
Cell Physiol Biochem. 2022 Jul 20;56(4):329-339. doi: 10.33594/000000553.
BACKGROUND/AIMS: Increase in vascular permeability is a cardinal feature of all inflammatory diseases and represents an imbalance in vascular contractile forces and barrier-restorative forces, both of which are highly dependent on actin cytoskeletal dynamics. In addition to the involvement of key vascular barrier-regulatory, actin-binding proteins, such as nmMLCK and cortactin, we recently demonstrated a role for a member of the Ena-VASP family known as Ena-VASP-like (EVL) in promoting vascular focal adhesion (FA) remodeling and endothelial cell (EC) barrier restoration/preservation.
To further understand the role of EVL in EC barrier-regulatory processes, we examined EVL-cytoskeletal protein interactions in FA dynamics in vitro utilizing lung EC and in vivo murine models of acute inflammatory lung injury. Deletion mapping studies and immunoprecipitation assays were performed to detail the interaction between EVL and cortactin, and further evaluated by assessment of changes in vascular EC permeability following disruption of EVL-cortactin interaction.
Initial studies focusing on the actin-binding proteins, nmMLCK and cortactin, utilized deletion mapping of the cortactin gene (CTTN) to identify cortactin domains critical for EVL-cortactin interaction and verified the role of actin in promoting EVL-cortactin interaction. A role for profilins, actin-binding proteins that regulate actin polymerization, was established in facilitating EVL-FA binding.
In summary, these studies further substantiate EVL participation in regulation of vascular barrier integrity and in the highly choreographed cytoskeletal interactions between key FA and cytoskeletal partners.
背景/目的：血管通透性的增加是所有炎症性疾病的主要特征，代表着血管收缩力和屏障修复力之间的失衡，这两者都高度依赖于肌动蛋白细胞骨架动力学。除了涉及关键的血管屏障调节肌动蛋白结合蛋白，如 nmMLCK 和 cortactin 外，我们最近还证明了 Ena-VASP 家族的一个成员 Ena-VASP-like（EVL）在促进血管焦点黏附（FA）重塑和内皮细胞（EC）屏障修复/维持中的作用。
为了进一步了解 EVL 在 EC 屏障调节过程中的作用，我们利用肺 EC 在体外的 FA 动力学和急性炎症性肺损伤的体内小鼠模型研究了 EVL-细胞骨架蛋白相互作用。进行了缺失作图研究和免疫沉淀分析，以详细描述 EVL 和 cortactin 之间的相互作用，并通过评估破坏 EVL-cortactin 相互作用后血管 EC 通透性的变化来进一步评估。
最初的研究集中在肌动蛋白结合蛋白 nmMLCK 和 cortactin 上，利用 cortactin 基因（CTTN）的缺失作图来识别对于 EVL-cortactin 相互作用至关重要的 cortactin 结构域，并验证了肌动蛋白在促进 EVL-cortactin 相互作用中的作用。肌动蛋白结合蛋白 Profilin 的作用，其调节肌动蛋白聚合，被确立为促进 EVL-FA 结合的作用。
总之，这些研究进一步证实了 EVL 参与调节血管屏障完整性，以及在关键 FA 和细胞骨架伙伴之间高度协调的细胞骨架相互作用。
