Department of Pharmacology, College of Medicine, Howard University, 520 W St., NW, Washington, DC, 20059, USA.
Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, New Orleans, LA, 70112, USA.
Cell Mol Neurobiol. 2022 Jan;42(1):255-263. doi: 10.1007/s10571-020-00951-x. Epub 2020 Aug 31.
We have previously shown that angiotensin-converting enzyme 2 (ACE2), an enzyme counterbalancing the deleterious effects of angiotensin type 1 receptor activation by production of vasodilatory peptides Angiotensin (Ang)-(1-9) and Ang-(1-7), is internalized and degraded in lysosomes following chronic Ang-II treatment. However, the molecular mechanisms involved in this effect remain unknown. In an attempt to identify the accessory proteins involved in this effect, we conducted a proteomic analysis in ACE2-transfected HEK293T cells. A single protein, fascin-1, was found to differentially interact with ACE2 after Ang-II treatment for 4 h. The interactions between fascin-1 and ACE2 were confirmed by confocal microscopy and co-immunoprecipitation. Overexpression of fascin-1 attenuates the effects of Ang-II on ACE2 activity. In contrast, downregulation of fascin-1 severely decreased ACE2 enzymatic activity. Interestingly, in brain homogenates from hypertensive mice, we observed a significant reduction of fascin-1, suggesting that the levels of this protein may change in cardiovascular diseases. In conclusion, we identified fascin-1 as an ACE2-accessory protein, interacting with the enzyme in an Ang-II dependent manner and contributing to the regulation of enzyme activity.
我们之前已经表明，血管紧张素转换酶 2（ACE2）是一种酶，通过产生血管舒张肽血管紧张素（Ang）-（1-9）和 Ang-（1-7）来抵消血管紧张素 1 型受体激活的有害影响，在慢性 Ang-II 处理后会被内吞和在溶酶体中降解。然而，这种作用涉及的分子机制尚不清楚。为了尝试鉴定参与这种作用的辅助蛋白，我们对 ACE2 转染的 HEK293T 细胞进行了蛋白质组学分析。在 Ang-II 处理 4 小时后，发现了一种名为 fascin-1 的单一蛋白与 ACE2 差异相互作用。通过共聚焦显微镜和共免疫沉淀证实了 fascin-1 和 ACE2 之间的相互作用。 fasci n-1 的过表达可减弱 Ang-II 对 ACE2 活性的影响。相反， fasci n-1 的下调严重降低了 ACE2 的酶活性。有趣的是，在高血压小鼠的脑匀浆中，我们观察到 fascin-1 的显著减少，这表明这种蛋白质的水平可能会在心血管疾病中发生变化。总之，我们将 fascin-1 鉴定为 ACE2 的辅助蛋白，它以 Ang-II 依赖的方式与该酶相互作用，并有助于调节酶活性。
