Department of Bacteriology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan.
Provost Office, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan.
Front Cell Infect Microbiol. 2023 Sep 15;13:1228051. doi: 10.3389/fcimb.2023.1228051. eCollection 2023.
disseminates hematogenously to reach the target organs by disrupting epithelial adherens junctions (AJs), thus causing leptospirosis, which is a globally neglected zoonotic disease. induces E-cadherin (E-cad) endocytosis and cytoskeletal rearrangement during AJ disassembly, but the detailed mechanism remains unknown. Elucidation of AJ disassembly mechanisms will guide new approaches to developing vaccines and diagnostic methods. In this study, we combine proteomic and imaging analysis with chemical inhibition studies to demonstrate that disrupting the AJs of renal proximal tubule epithelial cells involves the degradation of two armadillo repeat-containing proteins, p0071 and p120-catenin, that stabilize E-cad at the plasma membrane. Combining proteasomal and lysosomal inhibitors substantially prevented p120-catenin degradation, and monolayer integrity destruction without preventing p0071 proteolysis. In contrast, the pan-caspase inhibitor Z-VAD-FMK inhibited p0071 proteolysis and displacement of both armadillo repeat-containing proteins from the cell-cell junctions. Our results show that induces p120-catenin and p0071 degradation, which mutually regulates E-cad stability by co-opting multiple cellular degradation pathways. This strategy may allow to disassemble AJs and disseminate through the body efficiently.
它通过破坏上皮细胞黏附连接(AJ)在血液中传播,到达靶器官,从而引起莱姆病,这是一种被广泛忽视的人畜共患疾病。在 AJ 解体过程中, 诱导 E-钙黏蛋白(E-cad)内吞作用和细胞骨架重排,但详细的机制尚不清楚。阐明 AJ 解体的机制将为开发疫苗和诊断方法提供新的途径。在这项研究中,我们将蛋白质组学和成像分析与化学抑制研究相结合,证明破坏肾近端小管上皮细胞的 AJs 涉及两种富含角蛋白重复蛋白的降解,即 p0071 和 p120-连环蛋白,它们稳定 E-cad 在质膜上。联合使用蛋白酶体和溶酶体抑制剂可显著阻止 p120-连环蛋白的降解,并破坏单层完整性而不阻止 p0071 的蛋白水解。相比之下,泛半胱天冬酶抑制剂 Z-VAD-FMK 抑制了 p0071 的蛋白水解和两种富含角蛋白重复蛋白从细胞-细胞连接处的位移。我们的结果表明, 诱导 p120-连环蛋白和 p0071 降解,通过共激活多种细胞降解途径,相互调节 E-cad 的稳定性。这种策略可能使 有效地解体 AJ 并在体内传播。