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ELife Jul 2024Tubulin posttranslational modifications (PTMs) modulate the dynamic properties of microtubules and their interactions with other proteins. However, the effects of...
Tubulin posttranslational modifications (PTMs) modulate the dynamic properties of microtubules and their interactions with other proteins. However, the effects of tubulin PTMs were often revealed indirectly through the deletion of modifying enzymes or the overexpression of tubulin mutants. In this study, we directly edited the endogenous tubulin loci to install PTM-mimicking or -disabling mutations and studied their effects on microtubule stability, neurite outgrowth, axonal regeneration, cargo transport, and sensory functions in the touch receptor neurons of . We found that the status of β-tubulin S172 phosphorylation and K252 acetylation strongly affected microtubule dynamics, neurite growth, and regeneration, whereas α-tubulin K40 acetylation had little influence. Polyglutamylation and detyrosination in the tubulin C-terminal tail had more subtle effects on microtubule stability likely by modulating the interaction with kinesin-13. Overall, our study systematically assessed and compared several tubulin PTMs for their impacts on neuronal differentiation and regeneration and established an in vivo platform to test the function of tubulin PTMs in neurons.
Topics: Animals; Tubulin; Protein Processing, Post-Translational; Caenorhabditis elegans; Microtubules; Caenorhabditis elegans Proteins; Acetylation; Axons; Phosphorylation; Nerve Regeneration; Kinesins
PubMed: 38949652
DOI: 10.7554/eLife.94583 -
Molecular Cancer Research : MCR Jul 2024Because of its insensitivity to existing radiotherapy, namely chemotherapy and targeted treatments, triple-negative breast cancer (TNBC) remains a great challenge to...
Because of its insensitivity to existing radiotherapy, namely chemotherapy and targeted treatments, triple-negative breast cancer (TNBC) remains a great challenge to overcome. Increasing evidence has indicated abnormal Wnt/β-catenin pathway activation in TNBC but not luminal or HER2+ breast cancer, and lncRNAs play a key role in a variety of cancers. Through lncRNA microarray profiling between activated and inactivated wnt/β-catenin pathway of TNBC tissues, lnc-WAL (wnt/β-catenin associated lncRNA; WAL) was selected as the top upregulated lncRNA in wnt/β-catenin pathway activation compared with the inactivation group. RIP-seq was used to compare the β-catenin and IgG groups, where lnc-WAL could interact with β-catenin. Clinically, increased lnc-WAL in TNBC tumor tissue was associated with shorter survival. lnc-WAL promoted EMT, the proliferation, migration and invasion of breast cancer stem cells (BCSCs), and TNBC cells. Mechanistically, lnc-WAL inhibited β-catenin protein degradation via Axin-mediated phosphorylation at serine 45. Subsequently, β-catenin accumulated in the nucleus and activated the target genes. Importantly, wnt/β-catenin pathway activation stimulated the transcription of lnc-WAL. These results pointed to a master regulatory role of lnc-WAL/Axin/β-catenin in the malignant progression of TNBC. Our findings provide important clinical translational evidence that lnc-WAL may be a potential therapeutic target against TNBC. Implications: The positive feedback between lnc-WAL and the Wnt/β-catenin pathway promotes TNBC progression, and lnc-WAL could be a potential prognostic marker for TNBC patients.
PubMed: 38949521
DOI: 10.1158/1541-7786.MCR-23-0334 -
Zhonghua Kou Qiang Yi Xue Za Zhi =... Jul 2024To investigate the effects of Porphyromonas gingivalis (Pg) persisters (Ps) on immuno-inflammatory responses in macrophages, and to explore the underlying mechanisms....
To investigate the effects of Porphyromonas gingivalis (Pg) persisters (Ps) on immuno-inflammatory responses in macrophages, and to explore the underlying mechanisms. Pg cells were cultured to the stationary phase (72 h), and subsequently treated by high concentration of metronidazole at 100 mg/L, amoxicillin at 100 mg/L and the combination of them for different time period, named as metronidazole group, amoxicillin group and (metronidazole+amoxicillin) group. Pg cells without management were used as blank control. The survival profile of PgPs cells was measured by colony-forming unit assay. The living state of PgPs was observed by Live/Dead staining. Then, Pg and metronidazole-treated PgPs (M-PgPs) were used to treat macrophages, named as Pg group and M-PgPs group. Transmission electron microscopy (TEM) was used to observe the bacteria in the macrophages. The expression levels of proinflammatory cytokines in macrophages were determined by real-time fluorescence quantitative PCR and enzyme-linked immunosorbent assay. The location of forkhead box 1 (FOXO1) was detected by confocal immunofluorescence microscopy. After inhibiting or enhancing the FOXO1 expressions using inhibitors (Fi) or activators (Fa) respectively, the macrophages were treated with Pg and M-PgPs, divided as Blank group, Pg group, M-PgPs group, Fi group, (Fi+Pg) group, (Fi+M-PgPs) group, Fa group, (Fa+Pg) group and (Fa+M-PgPs) group. Then, the expression pattens of proinflammatory cytokines were assessed. Remarkable number of lived PgPs was observed, both in planktonic culture and Pg biofilms either treated with metronidazole, amoxicillin or both, and those persisters could form new colonies. Pg and M-PgPs were able to enter into the macrophages and the protein expression levels of interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor-α (TNF-α) [Pg group: (2 392±188), (162±29), (5 558±661), (789±155) μg/L; M-PgPs group: (2 415±420), (155±3), (5 732±782), (821±176) μg/L)] were significantly upregulated than those in Blank group [(485±140), (21±9), (2 332±87), (77±7) μg/L] (0.01). Moreover, Pg and M-PgPs could facilitate the nuclear translocation and accumulation of FOXO1. In addition, the relative mRNA expression levels of FOXO1, BCL6 and KLF2 were upregulated when compared to Blank group (0.05). Furthermore, the protein expression levels of IL-1β, IL-6, IL-8 and TNF-α in Fi+Pg group [(1 081±168), (70±8), (1 976±544), (420±47) μg/L] were remarkably lower than Pg group [(4 411±137), (179±6), (5 161±929), (934±24) μg/L] (0.05). Similarly, the protein expression levels of IL-1β, IL-6, IL-8 and TNF-α in Fi+M-PgPs group [(1 032±237), (74±10), (1 861±614), (405±32) μg/L] were remarkably lower than M-PgPs group [(4 342±314), (164±17), (4 438±1 374), (957±25) μg/L] (0.05). On the contrary, the protein expression levels of IL-1β, IL-6, IL-8 and TNF-α in Fa+Pg group [(8 198±1 825), (431±28), (8 919±650), (2 186±301) μg/L] and Fa+M-PgPs group [(8 159±2 627), (475±26), (8 995±653), (2 255±387 μg/L) were both significantly higher than Pg group and M-PgPs group, respectively (0.05). PgPs are highly tolerant to metronidazole and amoxicillin. The M-PgPs could enhance the immuno-inflammatory responses in macrophages by upregulating the FOXO1 signaling pathway, while this effect exhibits no significant difference with Pg.
PubMed: 38949135
DOI: 10.3760/cma.j.cn112144-20231114-00248 -
The Journal of Clinical Investigation Jul 2024Ubiquitination plays an essential role in protein stability, subcellular localization, and interactions. Crosstalk between different types of ubiquitination results in...
Ubiquitination plays an essential role in protein stability, subcellular localization, and interactions. Crosstalk between different types of ubiquitination results in distinct biological outcomes for proteins. However, the role of ubiquitination-related crosstalk in lymph node (LN) metastasis and the key regulatory factors controlling this process have not been determined. Using high-throughput sequencing, we found that ubiquitin-conjugating enzyme E2 C (UBE2C) was overexpressed in bladder cancer (BCa) and was strongly associated with an unfavorable prognosis. Overexpression of UBE2C increased BCa lymphangiogenesis and promoted LN metastasis both in vitro and in vivo. Mechanistically, UBE2C mediated sodium-coupled neutral amino acid transporter 2 (SNAT2) monoubiquitination at lysine 59 to inhibit K63-linked polyubiquitination at lysine 33 of SNAT2. Crosstalk between monoubiquitination and K63-linked polyubiquitination increased SNAT2 membrane protein levels by suppressing epsin 1-mediated (EPN1-mediated) endocytosis. SNAT2 facilitated glutamine uptake and metabolism to promote VEGFC secretion, ultimately leading to lymphangiogenesis and LN metastasis in patients with BCa. Importantly, inhibition of UBE2C significantly attenuated BCa lymphangiogenesis in a patient-derived xenograft model. Our results reveal the mechanism by which UBE2C mediates crosstalk between the monoubiquitination and K63-linked polyubiquitination of SNAT2 to promote BCa metastasis and identify UBE2C as a promising target for treating LN-metastatic BCa.
Topics: Ubiquitin-Conjugating Enzymes; Humans; Ubiquitination; Urinary Bladder Neoplasms; Animals; Lymphatic Metastasis; Mice; Cell Line, Tumor; Lymphangiogenesis; Female; Male; Vascular Endothelial Growth Factor C; Neoplasm Proteins; Minor Histocompatibility Antigens; Amino Acid Transport System ASC
PubMed: 38949026
DOI: 10.1172/JCI179122 -
The Journal of Clinical Investigation Jul 2024Mitochondria-related neurodegenerative diseases have been implicated in the disruption of primary cilia function. Mutation in an intrinsic mitochondrial complex I...
Mitochondria-related neurodegenerative diseases have been implicated in the disruption of primary cilia function. Mutation in an intrinsic mitochondrial complex I component NDUFAF2 has been identified in Leigh syndrome, a severe inherited mitochondriopathy. Mutations in ARMC9, which encodes a basal body protein, cause Joubert syndrome, a ciliopathy with defects in the brain, kidney, and eye. Here, we report a mechanistic link between mitochondria metabolism and primary cilia signaling. We discovered that loss of NDUFAF2 caused both mitochondrial and ciliary defects in vitro and in vivo and identified NDUFAF2 as a binding partner for ARMC9. We also found that NDUFAF2 was both necessary and sufficient for cilia formation and that exogenous expression of NDUFAF2 rescued the ciliary and mitochondrial defects observed in cells from patients with known ARMC9 deficiency. NAD+ supplementation restored mitochondrial and ciliary dysfunction in ARMC9-deficient cells and zebrafish and ameliorated the ocular motility and motor deficits of a patient with ARMC9 deficiency. The present results provide a compelling mechanistic link, supported by evidence from human studies, between primary cilia and mitochondrial signaling. Importantly, our findings have significant implications for the development of therapeutic approaches targeting ciliopathies.
Topics: Humans; Zebrafish; Leigh Disease; Cilia; Animals; Mitochondria; Kidney Diseases, Cystic; Electron Transport Complex I; Armadillo Domain Proteins; Retina; Eye Abnormalities; Mice; Abnormalities, Multiple; Cerebellum; Mitochondrial Proteins; Zebrafish Proteins; Male
PubMed: 38949024
DOI: 10.1172/JCI175560 -
The Journal of Clinical Investigation Jul 2024Cystic fibrosis is a debilitating disease characterized by a poor medical prognosis due to devastating lung injury. Recent medical advances targeting the major genetic...
Cystic fibrosis is a debilitating disease characterized by a poor medical prognosis due to devastating lung injury. Recent medical advances targeting the major genetic mutation ΔF508 of the cystic fibrosis transmembrane conductance regulator (CFTR) protein have dramatically increased the lifespan of patients with this mutation. This development has led to major changes in the field and has pushed research beyond the ion transport nature of cystic fibrosis and toward multiorgan physiological reprogramming. In this issue of the JCI, Bae, Kim, and colleagues utilized a large animal pig model prior to the onset of disease. They revealed metabolic reprogramming and organ crosstalk that occurred prior to disease progression. These findings provide paradigm-shifting insight into this complex disease.
Topics: Cystic Fibrosis; Animals; Humans; Cystic Fibrosis Transmembrane Conductance Regulator; Swine; Disease Models, Animal
PubMed: 38949023
DOI: 10.1172/JCI182329 -
Oncoimmunology 2024Deregulation or loss of the human leukocyte antigen class I (HLA-I) molecules on tumor cells leading to inhibition of CD8 T cell recognition is an important tumor immune...
Deregulation or loss of the human leukocyte antigen class I (HLA-I) molecules on tumor cells leading to inhibition of CD8 T cell recognition is an important tumor immune escape strategy, which could be caused by a posttranscriptional control of molecules in the HLA-I pathway mediated by RNA-binding proteins (RBPs). So far, there exists only limited information about the interaction of RBPs with HLA-I-associated molecules, but own work demonstrated a binding of the heterogeneous ribonucleoprotein C (hnRNP C) to the 3' untranslated region (UTR) of the TAP-associated glycoprotein tapasin (tpn). In this study, analysis of pan-cancer TCGA datasets revealed that hnRNP C is higher expressed in tumor specimens compared to corresponding normal tissues, which is negatively correlated to tpn expression, T cell infiltration and the overall survival of tumor patients. Functional analysis demonstrated an upregulation of tpn expression upon siRNA-mediated downregulation of hnRNP C, which is accompanied by an increased HLA-I surface expression. Thus, hnRNP C has been identified to target tpn and its inhibition could improve the HLA-I surface expression on melanoma cells suggesting its use as a possible biomarker for T-cell-based tumor immunotherapies.
Topics: Humans; Melanoma; Heterogeneous-Nuclear Ribonucleoprotein Group C; 3' Untranslated Regions; Membrane Transport Proteins; Cell Line, Tumor; Gene Expression Regulation, Neoplastic
PubMed: 38948930
DOI: 10.1080/2162402X.2024.2370928 -
BioRxiv : the Preprint Server For... Jun 2024Bed bugs are blood-feeders that rapidly proliferate into large indoor infestations. Their bites can cause allergies, secondary infections and psychological stress, among...
Bed bugs are blood-feeders that rapidly proliferate into large indoor infestations. Their bites can cause allergies, secondary infections and psychological stress, among other problems. Although several tactics for their management have been used, bed bugs continue to spread worldwide wherever humans reside. This is mainly due to human-mediated transport and their high resistance to several classes of insecticides. New treatment options with novel modes of action are required for their control. In this study, we evaluated the use of nitisinone (NTBC), an FDA-approved drug, for bed bug control in an insecticide-susceptible (HH) and an insecticide-resistant (CIN) population. Although NTBC was lethal to both populations when administered orally or applied topically in very low doses, we observed a slight but significant resistance in the CIN population. Transcriptomic analysis in both populations indicated that NTBC treatment elicited a broad suppression of genes associated with RNA post-transcriptional modifications, translation, endomembrane system, protein post-translational modifications and protein folding. The CIN population exhibited higher ATP production and xenobiotic detoxification. Feeding studies on a mouse model highlight that NTBC could be used as a control method of bed bugs by host treatment. The results demonstrate that NTBC can be used as a new active ingredient for bed bug control by topical or oral treatment and shed light on the molecular mechanisms of suppressed tyrosine metabolism following NTBC treatment.
PubMed: 38948842
DOI: 10.1101/2024.06.18.599347 -
BioRxiv : the Preprint Server For... Jun 2024The physiological response of a cell to stimulation depends on its proteome configuration. Therefore, the abundance variation of regulatory proteins across unstimulated...
The physiological response of a cell to stimulation depends on its proteome configuration. Therefore, the abundance variation of regulatory proteins across unstimulated single cells can be associatively linked with their response to stimulation. Here we developed an approach that leverages this association across individual cells and nuclei to systematically identify potential regulators of biological processes, followed by targeted validation. Specifically, we applied this approach to identify regulators of nucleocytoplasmic protein transport in macrophages stimulated with lipopolysaccharide (LPS). To this end, we quantified the proteomes of 3,412 individual nuclei, sampling the dynamic response to LPS treatment, and linking functional variability to proteomic variability. Minutes after the stimulation, the protein transport in individual nuclei correlated strongly with the abundance of known protein transport regulators, thus revealing the impact of natural protein variability on functional cellular response. We found that simple biophysical constraints, such as the quantity of nuclear pores, partially explain the variability in LPS-induced nucleocytoplasmic transport. Among the many proteins newly identified to be associated with the response, we selected 16 for targeted validation by knockdown. The knockdown phenotypes confirmed the inferences derived from natural protein and functional variation of single nuclei, thus demonstrating the potential of (sub-)single-cell proteomics to infer functional regulation. We expect this approach to generalize to broad applications and enhance the functional interpretability of single-cell omics data.
PubMed: 38948785
DOI: 10.1101/2024.06.17.599449 -
BioRxiv : the Preprint Server For... Jun 2024HIV-induced persistent immune activation is a key mediator of inflammatory comorbidities such as cardiovascular disease (CVD) and neurocognitive disorders. While a...
HIV-induced persistent immune activation is a key mediator of inflammatory comorbidities such as cardiovascular disease (CVD) and neurocognitive disorders. While a preponderance of data indicate that gut barrier disruption and microbial translocation are drivers of chronic immune activation, the molecular mechanisms of this persistent inflammatory state remain poorly understood. Here, utilizing the nonhuman primate model of HIV infection with suppressive antiretroviral therapy (ART), we investigated activation of inflammasome pathways and their association with intestinal epithelial barrier disruption and CVD pathogenesis. Longitudinal blood samples obtained from rhesus macaques with chronic SIV infection and long-term suppressive ART were evaluated for biomarkers of intestinal epithelial barrier disruption (IEBD), inflammasome activation (IL-1β and IL-18), inflammatory cytokines, and triglyceride (TG) levels. Activated monocyte subpopulations and glycolytic potential were investigated in peripheral blood mononuclear cells (PBMCs). Higher plasma levels of IL-1β and IL-18 were observed following the hallmark increase in IEBD biomarkers, intestinal fatty acid-binding protein (IFABP) and LPS-binding protein (LBP), during the chronic phase of treated SIV infection. Further, significant correlations of plasma IFABP levels with IL-1β and IL-18 were observed between 10-12 months of ART. Higher levels of sCD14, IL-6, and GM-CSF, among other inflammatory mediators, were also observed only during the long-term SIV+ART phase along with a trend of increase in frequencies of activated CD14 CD16 intermediate monocyte subpopulations. Lastly, we found elevated levels of blood TG and higher glycolytic capacity in PBMCs of chronic SIV-infected macaques with long-term ART. The increase in circulating IL-18 and IL-1β following IEBD and their significant positive correlation with IFABP suggest a connection between gut barrier disruption and inflammasome activation during chronic SIV infection, despite viral suppression with ART. Additionally, the increase in markers of monocyte activation, along with elevated TG and enhanced glycolytic pathway activity, indicates metabolic remodeling that could accelerate CVD pathogenesis. Further research is needed to understand mechanisms by which gut dysfunction and inflammasome activation contribute to HIV-associated CVD and metabolic complications, enabling targeted interventions in people with HIV.
PubMed: 38948748
DOI: 10.1101/2024.06.14.599106