scholarly journals Non-Canonical Binding of a Small Molecule to Sortilin Alters Cellular Trafficking of ApoB and PCSK9 in Liver Derived Cells

2019 ◽  
Author(s):  
Robert P. Sparks ◽  
Andres S. Arango ◽  
Zachary L. Aboff ◽  
Jermaine L. Jenkins ◽  
Wayne C. Guida ◽  
...  
Keyword(s):  
Small Molecule ◽  
Cellular Trafficking ◽  
Dependent Manner ◽  
Lysosomal Protease ◽  
Hepatic Cells ◽  
Evolutionarily Conserved

ABSTRACTSortilin regulates hepatic exocytosis and endocytosis of ApoB containing lipoproteins (ApoB-Lp) and mediates the secretion of the subtilase PCSK9. To elucidate connections between these pathways, we previously identified a small molecule (cpd984) that binds to a non-canonical site on Sortilin. In hepatic cells cpd984 augments ApoB-Lp secretion, increases cellular PCSK9 levels, and reduces LDLR expression indicative of reduced secretion of PCSK9. We have shown that insulin-induced ApoB-Lp degradation occurs through Vps34-dependent autophagy. Here we show that the specific Vps34 inhibitor PIK-III enhances ApoB-100 secretion, reducing cellular levels of PCSK9 and Sortilin resulting in reduced LDLR expression, which implicates a role for autophagy in PCSK9 secretion. Results suggest that Sortilin is central to both PCSK9 and ApoB-100 secretion. Finally, we found that cpd984 in yeast blocks CPY secretion while increasing vacuolar homotypic fusion in a Vps10-dependent manner, indicating an evolutionarily conserved mechanism required for lysosomal protease trafficking.

scholarly journals Small molecule induces mitochondrial fusion for neuroprotection via targeting CK2 without affecting its conventional kinase activity

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ke-Wu Zeng ◽  
Jing-Kang Wang ◽  
Li-Chao Wang ◽  
Qiang Guo ◽  
Ting-Ting Liu ◽  
...  
Keyword(s):  
Small Molecule ◽  
Nuclear Translocation ◽  
Fusion Gene ◽  
Artery Occlusion ◽  
Mitochondrial Fusion ◽  
Dependent Manner ◽  
Behavioral Deficits ◽  
Α Subunit ◽  
Cellular Target ◽  
Cerebral Artery Occlusion

AbstractMitochondrial fusion/fission dynamics plays a fundamental role in neuroprotection; however, there is still a severe lack of therapeutic targets for this biological process. Here, we found that the naturally derived small molecule echinacoside (ECH) significantly promotes mitochondrial fusion progression. ECH selectively binds to the previously uncharacterized casein kinase 2 (CK2) α′ subunit (CK2α′) as a direct cellular target, and genetic knockdown of CK2α′ abolishes ECH-mediated mitochondrial fusion. Mechanistically, ECH allosterically regulates CK2α′ conformation to recruit basic transcription factor 3 (BTF3) to form a binary protein complex. Then, the CK2α′/BTF3 complex facilitates β-catenin nuclear translocation to activate TCF/LEF transcription factors and stimulate transcription of the mitochondrial fusion gene Mfn2. Strikingly, in a mouse middle cerebral artery occlusion (MCAO) model, ECH administration was found to significantly improve cerebral injuries and behavioral deficits by enhancing Mfn2 expression in wild-type but not CK2α′+/− mice. Taken together, our findings reveal, for the first time, that CK2 is essential for promoting mitochondrial fusion in a Wnt/β-catenin-dependent manner and suggest that pharmacologically targeting CK2 is a promising therapeutic strategy for ischemic stroke.

scholarly journals Transcriptional perturbation of protein arginine methyltransferase-5 exhibits MTAP-selective oncosuppression

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sara Busacca ◽  
Qi Zhang ◽  
Annabel Sharkey ◽  
Alan G. Dawson ◽  
David A. Moore ◽  
...  
Keyword(s):  
Small Molecule ◽  
Selective Vulnerability ◽  
Dependent Manner ◽  
Histone H4 ◽  
Wild Type ◽  
Protein Arginine Methyltransferase ◽  
Arginine Methyltransferase ◽  
Methylthioadenosine Phosphorylase ◽  
Protein Arginine Methyltransferase 5

AbstractWe hypothesized that small molecule transcriptional perturbation could be harnessed to target a cellular dependency involving protein arginine methyltransferase 5 (PRMT5) in the context of methylthioadenosine phosphorylase (MTAP) deletion, seen frequently in malignant pleural mesothelioma (MPM). Here we show, that MTAP deletion is negatively prognostic in MPM. In vitro, the off-patent antibiotic Quinacrine efficiently suppressed PRMT5 transcription, causing chromatin remodelling with reduced global histone H4 symmetrical demethylation. Quinacrine phenocopied PRMT5 RNA interference and small molecule PRMT5 inhibition, reducing clonogenicity in an MTAP-dependent manner. This activity required a functional PRMT5 methyltransferase as MTAP negative cells were rescued by exogenous wild type PRMT5, but not a PRMT5E444Q methyltransferase-dead mutant. We identified c-jun as an essential PRMT5 transcription factor and a probable target for Quinacrine. Our results therefore suggest that small molecule-based transcriptional perturbation of PRMT5 can leverage a mutation-selective vulnerability, that is therapeutically tractable, and has relevance to 9p21 deleted cancers including MPM.

scholarly journals Drug-Like Small Molecule HSP27 Functional Inhibitor Sensitizes Lung Cancer Cells to Gefitinib or Cisplatin by Inducing Altered Cross-Linked Hsp27 Dimers

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 630
Author(s):  
Hawon Yoo ◽  
Seul-Ki Choi ◽  
Jaeok Lee ◽  
So Hyeon Park ◽  
You Na Park ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Drug Resistance ◽  
Cancer Cells ◽  
Cell Lines ◽  
Small Molecule ◽  
Anticancer Agents ◽  
Tumor Growth Inhibition ◽  
Dependent Manner ◽  
Hsp27 Expression ◽  
Cancer Aggressiveness

Relationships between heat shock protein 27 (HSP27) and cancer aggressiveness, metastasis, drug resistance, and poor patient outcomes in various cancer types including non-small cell lung cancer (NSCLC) were reported, and inhibition of HSP27 expression is suggested to be a possible strategy for cancer therapy. Unlike HSP90 or HSP70, HSP27 does not have an ATP-binding pocket, and no effective HSP27 inhibitors have been identified. Previously, NSCLC cancer cells were sensitized to radiation and chemotherapy when co-treated with small molecule HSP27 functional inhibitors such as zerumbone (ZER), SW15, and J2 that can induce abnormal cross-linked HSP27 dimer. In this study, cancer inhibition effects of NA49, a chromenone compound with better solubility, longer circulation time, and less toxicity than J2, were examined in combination with anticancer drugs such as cisplatin and gefitinib in NSCLC cell lines. When the cytotoxic drug cisplatin was treated in combination with NA49 in epidermal growth factor receptors (EGFRs) WT cell lines, sensitization was induced in an HSP27 expression-dependent manner. With gefitinib treatment, NA49 showed increased combination effects in both EGFR WT and Mut cell lines, also with HSP27 expression-dependent patterns. Moreover, NA49 induced sensitization in EGFR Mut cells with a secondary mutation of T790M when combined with gefitinib. Augmented tumor growth inhibition was shown with the combination of cisplatin or gefitinib and NA49 in nude mouse xenograft models. These results suggest the combination of HSP27 inhibitor NA49 and anticancer agents as a candidate for overcoming HSP27-mediated drug resistance in NSCLC patients.

scholarly journals Disassembly of theStaphylococcus aureushibernating 100S ribosome by an evolutionarily conserved GTPase

2017 ◽  
Vol 114 (39) ◽  
pp. E8165-E8173 ◽  
Author(s):  
Arnab Basu ◽  
Mee-Ngan F. Yap
Keyword(s):  
Opportunistic Pathogen ◽  
Dependent Manner ◽  
Bacterial Survival ◽  
Temperature Dependent ◽  
Bacterial Phyla ◽  
Evolutionarily Conserved ◽  
Bona Fide ◽  
70S Ribosome ◽  
Relationship Of ◽  
Dissociation Factor

The bacterial hibernating 100S ribosome is a poorly understood form of the dimeric 70S particle that has been linked to pathogenesis, translational repression, starvation responses, and ribosome turnover. In the opportunistic pathogenStaphylococcus aureusand most other bacteria, hibernation-promoting factor (HPF) homodimerizes the 70S ribosomes to form a translationally silent 100S complex. Conversely, the 100S ribosomes dissociate into subunits and are presumably recycled for new rounds of translation. The regulation and disassembly of the 100S ribosome are largely unknown because the temporal abundance of the 100S ribosome varies considerably among different bacterial phyla. Here, we identify a universally conserved GTPase (HflX) as a bona fide dissociation factor of theS. aureus100S ribosome. The expression levelshpfandhflXare coregulated by general stress and stringent responses in a temperature-dependent manner. While all tested guanosine analogs stimulate the splitting activity of HflX on the 70S ribosome, only GTP can completely dissociate the 100S ribosome. Our results reveal the antagonistic relationship of HPF and HflX and uncover the key regulators of 70S and 100S ribosome homeostasis that are intimately associated with bacterial survival.

scholarly journals CFP-1 interacts with HDAC1/2 complexes inC. elegansdevelopment

2018 ◽  
Author(s):  
Bharat Pokhrel ◽  
Yannic Chen ◽  
Jonathan Joseph Biro
Keyword(s):  
Cell Fate ◽  
Embryonic Stem ◽  
Stem Cell Differentiation ◽  
Embryonic Stem Cell Differentiation ◽  
Dependent Manner ◽  
Cell Fate Specification ◽  
C Elegans ◽  
Evolutionarily Conserved ◽  
Epigenetic Regulator ◽  
Inducible Genes

AbstractCFP-1 (CXXC finger binding protein 1) is an evolutionarily conserved protein that binds to non-methylated CpG-rich promoters in humans andC. elegans. This conserved epigenetic regulator is a part of the COMPASS complex that contains the H3K4me3 methyltransferase SET1 in mammals and SET-2 inC. elegans. Previous studies have indicated the importance ofcfp-1in embryonic stem cell differentiation and cell fate specification. However, neither the function nor the mechanism of action ofcfp-1is well understood at the organismal level. To further investigate the function of CFP-1, we have characterisedC. elegansCOMPASS mutantscfp-1(tm6369)andset-2(bn129). We found that bothcfp-1andset-2play an important role in the regulation of fertility and development of the organism. Furthermore, we found that bothcfp-1andset-2are required for H3K4 trimethylation and play a repressive role in the expression of heat shock and salt-inducible genes. Interestingly, we found thatcfp-1but notset-2genetically interacts with Histone Deacetylase (HDAC1/2) complexes to regulate fertility, suggesting a function of CFP-1 outside of the COMPASS complex. Additionally we found thatcfp-1andset-2acts on a separate pathways to regulate fertility and development ofC. elegans. Our results suggest that CFP-1 genetically interacts with HDAC1/2 complexes to regulate fertility, independent of its function within COMPASS complex. We propose that CFP-1 could cooperate with COMPASS complex and/or HDAC1/2 in a context dependent manner.

Discovery of a Novel Small-Molecule Interleukin-6 Inhibitor through Virtual Screening Using Artificial Intelligence

2021 ◽  
Vol 18 ◽  
Author(s):  
Yoshiaki Sato ◽  
Ikuo Kashiwakura ◽  
Masaru Yamaguchi ◽  
Hironori Yoshino ◽  
Takeshi Tanaka ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Small Molecule ◽  
Interleukin 6 ◽  
Inflammatory Diseases ◽  
Biological Activities ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Cell Functions ◽  
Dependent Cell ◽  
Dose Dependent

Background: Interleukin-6 (IL-6) is a multifunctional cytokine involved in various cell functions and diseases. Thus far, several IL-6 inhibitors, such as, humanized monoclonal antibody have been used to block excessive IL-6 signaling causing autoimmune and inflammatory diseases. However, anti-IL-6 and anti-IL-6 receptor monoclonal antibodies have some clinical disadvantages, such as a high cost, unfavorable injection route, and tendency to mask infectious diseases. While a small-molecule IL-6 inhibitor would help mitigate these issues, none are currently available. Objective: The present study evaluated the biological activities of identified compounds on IL-6 stimulus. Methods: We virtually screened potential IL-6 binders from a compound library using INTerprotein’s Engine for New Drug Design (INTENDD®) followed by the identification of more potent IL-6 binders with artificial intelligence (AI)-guided INTENDD®. The biological activities of the identified compounds were assessed with the IL-6-dependent cell line 7TD1. Results: The compounds showed the suppression of IL-6-dependent cell growth in a dose-dependent manner. Furthermore, the identified compound inhibited expression of IL-6-induced phosphorylation of signal transducer and activator of transcription 3 in a dose-dependent manner. Conclusion: Our screening compound demonstrated an inhibitory effect on IL-6 stimulus. These findings may serve as a basis for the further development of small-molecule IL-6 inhibitors.

scholarly journals Targeting the Initiator Protease of the Classical Pathway of Complement Using Fragment-Based Drug Discovery

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 4016
Author(s):  
Blake Rushing ◽  
Denise Rohlik ◽  
Sourav Roy ◽  
D. Skaff ◽  
Brandon Garcia
Keyword(s):  
Drug Discovery ◽  
Small Molecule ◽  
Dissociation Constants ◽  
Inflammatory Diseases ◽  
Alternative Pathway ◽  
Lectin Pathway ◽  
Classical Pathway ◽  
Dependent Manner ◽  
Intervention Point ◽  
Fragment Based Drug Discovery

The initiating protease of the complement classical pathway, C1r, represents an upstream and pathway-specific intervention point for complement-related autoimmune and inflammatory diseases. Yet, C1r-targeted therapeutic development is currently underrepresented relative to other complement targets. In this study, we developed a fragment-based drug discovery approach using surface plasmon resonance (SPR) and molecular modeling to identify and characterize novel C1r-binding small-molecule fragments. SPR was used to screen a 2000-compound fragment library for binding to human C1r. This led to the identification of 24 compounds that bound C1r with equilibrium dissociation constants ranging between 160–1700 µM. Two fragments, termed CMP-1611 and CMP-1696, directly inhibited classical pathway-specific complement activation in a dose-dependent manner. CMP-1611 was selective for classical pathway inhibition, while CMP-1696 also blocked the lectin pathway but not the alternative pathway. Direct binding experiments mapped the CMP-1696 binding site to the serine protease domain of C1r and molecular docking and molecular dynamics studies, combined with C1r autoactivation assays, suggest that CMP-1696 binds within the C1r active site. The group of structurally distinct fragments identified here, along with the structure–activity relationship profiling of two lead fragments, form the basis for future development of novel high-affinity C1r-binding, classical pathway-specific, small-molecule complement inhibitors.

scholarly journals Alp7-Mto1 and Alp14 synergize to promote interphase microtubule regrowth from the nuclear envelope

2019 ◽  
Vol 11 (11) ◽  
pp. 944-955 ◽  
Author(s):  
Wenyue Liu ◽  
Fan Zheng ◽  
Yucai Wang ◽  
Chuanhai Fu
Keyword(s):  
Nuclear Envelope ◽  
Schizosaccharomyces Pombe ◽  
Fission Yeast ◽  
Microtubule Assembly ◽  
Dependent Manner ◽  
Microtubule Nucleation ◽  
Microtubule Organizing Centers ◽  
Evolutionarily Conserved ◽  
Microtubule Growth ◽  
In Cells

Abstract Microtubules grow not only from the centrosome but also from various noncentrosomal microtubule-organizing centers (MTOCs), including the nuclear envelope (NE) and pre-existing microtubules. The evolutionarily conserved proteins Mto1/CDK5RAP2 and Alp14/TOG/XMAP215 have been shown to be involved in promoting microtubule nucleation. However, it has remained elusive as to how the microtubule nucleation promoting factors are specified to various noncentrosomal MTOCs, particularly the NE, and how these proteins coordinate to organize microtubule assembly. Here, we demonstrate that in the fission yeast Schizosaccharomyces pombe, efficient interphase microtubule growth from the NE requires Alp7/TACC, Alp14/TOG/XMAP215, and Mto1/CDK5RAP2. The absence of Alp7, Alp14, or Mto1 compromises microtubule regrowth on the NE in cells undergoing microtubule repolymerization. We further demonstrate that Alp7 and Mto1 interdependently localize to the NE in cells without microtubules and that Alp14 localizes to the NE in an Alp7 and Mto1-dependent manner. Tethering Mto1 to the NE in cells lacking Alp7 partially restores microtubule number and the efficiency of microtubule generation from the NE. Hence, our study delineates that Alp7, Alp14, and Mto1 work in concert to regulate interphase microtubule regrowth on the NE.

scholarly journals Exploring the effect of UV-C radiation on earthworm and understanding its genomic integrity in the context of H2AX expression

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Karthikeyan Subbiahanadar Chelladurai ◽  
Jackson Durairaj Selvan Christyraj ◽  
Ananthaselvam Azhagesan ◽  
Vennila Devi Paulraj ◽  
Muralidharan Jothimani ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Primary Response ◽  
Coelomic Fluid ◽  
Dependent Manner ◽  
Perionyx Excavatus ◽  
Dna Damages ◽  
Highly Sensitive ◽  
Evolutionarily Conserved ◽  
Uv C

AbstractMaintaining genomic stability is inevitable for organism survival and it is challenged by mutagenic agents, which include ultraviolet (UV) radiation. Whenever DNA damage occurs, it is sensed by DNA-repairing proteins and thereby performing the DNA-repair mechanism. Specifically, in response to DNA damage, H2AX is a key protein involved in initiating the DNA-repair processes. In this present study, we investigate the effect of UV-C on earthworm, Perionyx excavatus and analyzed the DNA-damage response. Briefly, we expose the worms to different doses of UV-C and find that worms are highly sensitive to UV-C. As a primary response, earthworms produce coelomic fluid followed by autotomy. However, tissue inflammation followed by death is observed when we expose worm to increased doses of UV-C. In particular, UV-C promotes damages in skin layers and on the contrary, it mediates the chloragogen and epithelial outgrowth in intestinal tissues. Furthermore, UV-C promotes DNA damages followed by upregulation of H2AX on dose-dependent manner. Our finding confirms DNA damage caused by UV-C is directly proportional to the expression of H2AX. In short, we conclude that H2AX is present in the invertebrate earthworm, which plays an evolutionarily conserved role in DNA damage event as like that in higher animals.

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