MOLECULAR CELL
·
2023
·
IF 16
Chenchen Xu,Xiaoqing Pan,Dong Wang,Yuanyuan Guan,Wenyu Yang,Xing Chen,Ying Liu
The mechanistic target of rapamycin complex 1 (mTORC1) regulates metabolism and cell growth in response to nutrient levels. Dysregulation of mTORC1 results in a broad spectrum of diseases. Glucose is the primary energy supply of cells, and therefore, glucose levels must be accurately conveyed to mTORC1 through highly responsive signaling mechanisms to control mTORC1 activity. Here, we report that glucose-induced mTORC1 activation is regulated by O-GlcNAcylation of Raptor, a core component of mTORC1, in HEK293T cells. Mechanistically, O-GlcNAcylation of Raptor at threonine 700 facilitates the interactions between Raptor and Rag GTPases and promotes the translocation of mTOR to the lysosomal surface, consequently activating mTORC1. In addition, we show that AMPK-mediated phosphorylation of Raptor suppresses Raptor O-GlcNAcylation and inhibits Raptor-Rags interactions. Our findings reveal an exquisitely controlled mechanism, which suggests how glucose coordinately regulates cellular anabolism and catabolism.
研究领域:
细胞生物学
·
分子生物学
·
代谢
·
信号通路
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ETHNOPHARMACOLOGY
·
2021
·
IF 4.36
Xing-Jie Zhang,Kun Shang,Yu-Kun Pu,Qi Wang,Ting-Ting Wang,Yan Zou,Yong-Mei Wang,Yao-Jun Xu,Xiao-Li Li,Rui-Han Zhang,Wei-Lie Xiao
Ethnopharmacological relevance Duan Teng Yimu decoction is a Chinese herbal medicine compound with proven therapeutic effects on inflammasome-related diseases, such as rheumatoid arthritis . This decoction consists of three Chinese herbal medicines, including Leonurus japonicus ( L. japonicus ), which promotes the blood circulation and exhibits detumescence activity, traditionally curing gynecologic and inflammasome diseases. Aim of the study To explore the anti-inflammasome activity and the underlying mechanisms of action of the compounds from L. japonicus . Materials and methods A series of compounds were isolated from L. japonicus . Their anti-inflammasome activities were evaluated in macrophages that were co-stimulated by lipopolysaccharide (LPS) and NLRP3 inflammasome inducers. NLRP3 inflammasome formation and apoptosis speck like containing a CARD (ASC) oligomerization were evaluated by immunofluorescent microscopy and Western blot analysis . The regulation of autophagy after treatment of this compound was also evaluated. Lastly, in vivo activity of Leojaponin was analyzed in a mouse acute gouty arthritis model. Results Here we show that Leojaponin, a diterpenoid compound from L. japonicus , suppressed lactate dehydrogenase and IL-1β release in Nigericin-stimulated macrophages in a pyroptosis model. Leojaponin inhibits NLRP3 inflammasome activation in both J774A.1 cells and bone marrow-derived macrophages in a dose dependent manner. Moreover, Leojaponin suppressed NLRP3-mediated ASC specks formation and ASC oligomerization. These activities of Leojaponin depend on restoration of autophagy via promoting RAPTOR phosphorylation. Furthermore, Leojaponin ameliorated monosodium urate (MSU)-induced acute gouty arthritis in vivo . Conclusion Our findings suggest that Leojaponin inhibits NLRP3 inflammasome activation through enhancing autophagy via RAPTOR phosphorylation, thereby highlighting Leojaponin as a potent drug for inflammasome-related diseases.
研究领域:
药理学
·
免疫学
·
传统中药
·
分子生物学
·
炎症
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELL AND TISSUE RESEARCH
·
2022
·Vol. 390
·期 2
·293-313
·
IF 4.051
Li Zhen-Fang,Hao Shuang-Li,Wang Lan-Min,Qi Hong-Yu,Wang Jia-Ming,Tan Fu-Qing,Yang Wan-Xi
Spermatogenesis is a finely regulated process of germ cell proliferation and differentiation that leads to the production of sperm in seminiferous tubules. Although the mammalian target of rapamycin (mTOR) signaling pathway is crucial for spermatogenesis in mammals, its functions and molecular mechanisms in spermatogenesis remain largely unknown in nonmammalian species, particularly in Crustacea. In this study, we first identified es-Raptor (the core component of mTOR complex 1) and es-Rictor (the core component of mTOR complex 2) from the testis of Eriocheir sinensis . Dynamic localization of es-Raptor and es-Rictor implied that these proteins were indispensable for the spermatogenesis of E. sinensis. Furthermore, es-Raptor and es-Rictor knockdown results showed that the mature sperm failed to be released, causing almost empty lumens in the testis. We investigated the reasons for these effects and found that the actin-based cytoskeleton was disrupted in the knockdown groups. In addition, the integrity of the testis barrier (similar to the blood-testis barrier in mammals) was impaired and affected the expression of cell junction proteins. Further study revealed that es-Raptor and es-Rictor may regulate spermatogenesis via both mTORC1- and mTORC2-dependent mechanisms that involve es-rpS6 and es-Akt/es-PKC, respectively. Moreover, to explore the testis barrier in E. sinensis , we established a cadmium chloride (CdCl 2 )–induced testis barrier damage model as a positive control. Morphological and immunofluorescence results were similar to those of the es-Raptor and es-Rictor knockdown groups. Altogether, es-Raptor and es-Rictor were important for spermatogenesis through maintenance of the actin filament network and cell junctions in E. sinensis.
研究领域:
分子生物学
·
生殖生物学
·
甲壳动物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PROTEOME RESEARCH
·
2023
·
IF 4.4
Mengmeng Zheng,Yanmei Zhang,Yao Xu,Ying Han,Yingli Wu,Jingwu Kang
Salvianolic acid A (SAA), a major active ingredient of Salvia miltiorrhiza Bunge (Danshen), displays strong antiproliferative activity against cancer cells. However, their protein targets remain unknown. Here, we deconvoluted the protein targets of SAA using chemoproteomics and phosphoproteomics. By using alkynylated SAA as a probe, we discovered that SAA is a covalent ligand that can modify cellular proteins via its electrophilic α,β-unsaturated ester moiety. The subsequent chemoproteomics profiling revealed that 46 proteins were covalently modified by SAA, including Raptor, a subunit of mTORC1 for recruiting substrates for mTORC1. Although gene ontology enrichment analysis of these proteins suggested that SAA displays a promiscuous protein interaction, phosphoproteomics profiling revealed that the SAA modulated phosphoproteins were mainly enriched in the signaling pathways of PI3K-Akt-mTOR, which is closely related to cell growth and proliferation. This was confirmed by the biochemical assay with purified mTORC1, a Western blot assay with phospho-specific antibodies, and a cellular thermal shift assay. Our work discovered that SAA is a covalent ligand for protein modification and mTORC1 is one of its targets. Moreover, our work demonstrated that the integrative profiling of chemoproteomics and phosphoproteomics can be a powerful tool for target deconvolution for bioactive natural products.
研究领域:
药理学
·
蛋白质组学
·
癌症研究
·
分子生物学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）