Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, NY, USA.
Nat Commun. 2024 Oct 29;15(1):9322. doi: 10.1038/s41467-024-53637-z.
The eukaryotic Glucose Induced Degradation/C-Terminal to LisH (GID/CTLH) complex is a highly conserved E3 ubiquitin ligase involved in a broad range of biological processes. However, a role of this complex in host anti-microbial defenses has not been described. We exploited Mycobacterium tuberculosis (Mtb) induced cytotoxicity in macrophages in a FACS based CRISPR genetic screen to identify host determinants of intracellular Mtb growth restriction. Our screen identified 5 (GID8, YPEL5, WDR26, UBE2H, MAEA) of the 12 predicted members of the GID/CTLH complex as determinants of intracellular growth of both Mtb and Salmonella serovar Typhimurium. We show that the anti-microbial properties of the GID/CTLH complex knockout macrophages are mediated by enhanced GABAergic signaling, activated AMPK, increased autophagic flux and resistance to Mtb induced necrotic cell death. Meanwhile, Mtb isolated from GID/CTLH knockout macrophages are nutritionally starved and oxidatively stressed. Our study identifies the GID/CTLH complex activity as broadly suppressive of host anti-microbial responses against intracellular bacterial infections.
真核生物葡萄糖诱导降解/C 末端到 LisH（GID/CTLH）复合物是一种高度保守的 E3 泛素连接酶，参与广泛的生物学过程。然而，该复合物在宿主抗微生物防御中的作用尚未被描述。我们利用基于 FACS 的 CRISPR 遗传筛选，研究了巨噬细胞中结核分枝杆菌（Mtb）诱导的细胞毒性，以鉴定宿主对细胞内 Mtb 生长限制的决定因素。我们的筛选确定了 GID/CTLH 复合物的 12 个预测成员中的 5 个（GID8、YPEL5、WDR26、UBE2H、MAEA）作为 Mtb 和沙门氏菌血清型鼠伤寒菌细胞内生长的决定因素。我们表明，GID/CTLH 复合物敲除巨噬细胞的抗微生物特性是通过增强 GABA 能信号、激活 AMPK、增加自噬通量和抵抗 Mtb 诱导的坏死性细胞死亡来介导的。同时，从 GID/CTLH 敲除巨噬细胞中分离出的 Mtb 受到营养饥饿和氧化应激的影响。我们的研究确定了 GID/CTLH 复合物的活性广泛抑制了宿主对细胞内细菌感染的抗微生物反应。
