National Institute of Pathology, ICMR, Safdarjung Hospital Campus, New Delhi, India.
Institute of Molecular Medicine, Jamia Hamdard, Hamdard Nagar, New Delhi, India.
Virulence. 2023 Dec;14(1):2180230. doi: 10.1080/21505594.2023.2180230.
() utilizes the multifunctionality of its protein factors to deceive the host. The unabated global incidence and prevalence of tuberculosis (TB) and the emergence of multidrug-resistant strains warrant the discovery of novel drug targets that can be exploited to manage TB. This study reports the role of AAA+ family protein MoxR1 in regulating host-pathogen interaction and immune system functions. We report that MoxR1 binds to TLR4 in macrophage cells and further reveal how this signal the release of proinflammatory cytokines. We show that MoxR1 activates the PI3K-AKT-MTOR signalling cascade by inhibiting the autophagy-regulating kinase ULK1 by potentiating its phosphorylation at serine 757, leading to its suppression. Using autophagy-activating and repressing agents such as rapamycin and bafilomycin A1 suggested that MoxR1 inhibits autophagy flux by inhibiting autophagy initiation. MoxR1 also inhibits apoptosis by suppressing the expression of MAPK JNK1/2 and cFOS, which play critical roles in apoptosis induction. Intriguingly, MoxR1 also induced robust disruption of cellular bioenergetics by metabolic reprogramming to rewire the citric acid cycle intermediates, as evidenced by the lower levels of citric acid and electron transport chain enzymes (ETC) to dampen host defence. These results point to a multifunctional role of MoxR1 in dampening host defences by inhibiting autophagy, apoptosis, and inducing metabolic reprogramming. These mechanistic insights can be utilized to devise strategies to combat TB and better understand survival tactics by intracellular pathogens.
() 利用其蛋白因子的多功能性来欺骗宿主。全球结核病(TB)的发病率和患病率持续上升,并且出现了耐多药菌株,这就需要发现新的药物靶点,以用于治疗结核病。本研究报告了 AAA+ 家族蛋白 MoxR1 在调节宿主-病原体相互作用和免疫系统功能中的作用。我们报告 MoxR1 与巨噬细胞中的 TLR4 结合,并进一步揭示了这种信号如何引发促炎细胞因子的释放。我们表明,MoxR1 通过抑制自噬调节激酶 ULK1 的磷酸化来激活 PI3K-AKT-MTOR 信号通路,从而使其被抑制。使用自噬激活和抑制剂,如雷帕霉素和巴弗洛霉素 A1,表明 MoxR1 通过抑制自噬起始来抑制自噬流。MoxR1 还通过抑制 MAPK JNK1/2 和 cFOS 的表达来抑制细胞凋亡,它们在凋亡诱导中起关键作用。有趣的是,MoxR1 还通过代谢重编程诱导强烈的细胞能量代谢破坏,重新布线柠檬酸循环中间体,这可以从柠檬酸和电子传递链酶(ETC)水平降低来证明,以抑制宿主防御。这些结果表明,MoxR1 通过抑制自噬、凋亡和诱导代谢重编程,在抑制宿主防御方面发挥多功能作用。这些机制见解可以用于制定对抗结核病的策略,并更好地理解细胞内病原体的生存策略。