Cell Reports
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2020
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IF 8.109
Lidia Wrobel,Farah H. Siddiqi,Sandra M. Hill,Sung Min Son,Cansu Karabiyik,Hyunjeong Kim,David C. Rubinsztein
Summary The mechanistic target of rapamycin complex 2 (mTORC2) controls cell metabolism and survival in response to environmental inputs. Dysregulation of mTORC2 signaling has been linked to diverse human diseases, including cancer and metabolic disorders, highlighting the importance of a tightly controlled mTORC2. While mTORC2 assembly is a critical determinant of its activity, the factors regulating this event are not well understood, and it is unclear whether this process is regulated by growth factors. Here, we present data, from human cell lines and mice, describing a mechanism by which growth factors regulate ubiquitin-specific protease 9X (USP9X) deubiquitinase to stimulate mTORC2 assembly and activity. USP9X removes Lys63-linked ubiquitin from RICTOR to promote its interaction with mTOR, thereby facilitating mTORC2 signaling. As mTORC2 is central for cellular homeostasis, understanding the mechanisms regulating mTORC2 activation toward its downstream targets is vital for our understanding of physiological processes and for developing new therapeutic strategies in pathology.
研究领域:
细胞生物学
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分子生物学
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癌症研究
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代谢研究
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DOI
PubMed
高影响因子
Human Cell
·
2025
·Vol. 38
·期 4
·1-13
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IF 3.1
Lian Hongyu,Yu Miao,Li Qi,Xiao Jiayi,Tang Xin,Zhang Bin,Liu Dongxue,Xu Yongliang,Dong Mo,Li Zitao,Yao Lihong,Li Caijuan
Hypoxia is a critical mechanism within the microenvironment of tumors. Exosomes, serve as conduits for intercellular communication and transport the biomolecule miRNA by facilitating intercellular signal exchange, which partially regulate cancer metastasis. Our research investigated whether the role of hypoxic breast cancer cell-derived exosomal miR-143-3p in cancer progression. Real-time PCR explored miR-143-3p expression in hypoxia breast cancer cell-derived exosomes. Co-culturing of breast cancer with hypoxia exosome-primed M0 macrophages, transwell detected the invasiveness of breast cancer cells. Western blot showed the effect of hypoxia exosomes on the levels of M2 makers in macrophages and the epithelial-mesenchymal transition (EMT) indicators in breast cancer cells. Bioinformatics prediction and dual luciferase reporter assay determined the interaction between miR-143-3p and RICTOR. We found that exosomal miR-143-3p expression was downregulated in hypoxic conditions. Hypoxia breast cancer cell-derived exosomal miR-143-3p negatively correlated with the presentation of the M2 macrophage marker CD206 and regulated the levels of Arg-1, CD206 and CD163 mRNA levels. In addition, hypoxia exosome-mediated polarization of M2 macrophages promotes breast cancer cell migration and invasion. Mechanistically, miR-143-3p acted antagonistically with RICTOR, thereby suppressing macrophage M2 polarization. In summary, our study reveals that the hypoxia downregulates the exosomal miR-143-3p derived from breast cancer cells to increase macrophage RICTOR expression, thereby promoting M2 macrophage polarization to enhance breast cancer cell invasiveness, suggesting that miR-143-3p may be a candidate molecule for microRNA alternative therapy in breast cancer.
研究领域:
肿瘤学
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分子生物学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
CELL AND TISSUE RESEARCH
·
2022
·Vol. 390
·期 2
·293-313
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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
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生殖生物学
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甲壳动物学
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产品关联
DOI
PubMed
高影响因子
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