Cell surface receptor-targeted protein degraders hold promise for drug discovery. However, their application is restricted because of the complexity of creating bifunctional degraders and the reliance on specific lysosome-shuttling receptors or E3 ubiquitin ligases. To address these limitations, we developed an autophagy-based plasma membrane protein degradation platform, which we term AUTABs (autophagy-inducing antibodies).
View Article and Find Full Text PDFThe default mode network (DMN) lies towards the heteromodal end of the principal gradient of intrinsic connectivity, maximally separated from the sensory-motor cortex. It supports memory-based cognition, including the capacity to retrieve conceptual and evaluative information from sensory inputs, and to generate meaningful states internally; however, the functional organisation of DMN that can support these distinct modes of retrieval remains unclear. We used fMRI to examine whether activation within subsystems of DMN differed as a function of retrieval demands, or the type of association to be retrieved, or both.
View Article and Find Full Text PDFThe Dll4-Notch signaling pathway plays a crucial role in the regulation of angiogenesis and is a promising therapeutic target for diseases associated with abnormal angiogenesis, such as cancer and ophthalmic diseases. Here, we find that polyethylenimine (PEI), a cationic polymer widely used as nucleic acid transfection reagents, can target the Notch ligand Dll4. By immunostaining and immunoblotting, we demonstrate that PEI significantly induces the clearance of cell-surface Dll4 and facilitates its degradation through the lysosomal pathway.
View Article and Find Full Text PDFAs effective ways to regulate protein levels, targeted protein degradation technologies have attracted great attention in recent years. Here, we established a novel integrin-facilitated lysosomal degradation (IFLD) strategy to degrade extracellular and cell membrane proteins using bifunctional compounds as molecular degraders. By conjugation of a target protein-binding ligand with an integrin-recognition ligand, the resulting molecular degrader proved to be highly efficient to induce the internalization and subsequent degradation of extracellular or cell membrane proteins in an integrin- and lysosome-dependent manner.
View Article and Find Full Text PDFThe global emergency caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic can only be solved with effective and widespread preventive and therapeutic strategies, and both are still insufficient. Here, we describe an ultrathin two-dimensional CuInPS (CIPS) nanosheet as a new agent against SARS-CoV-2 infection. CIPS exhibits an extremely high and selective binding capacity (dissociation constant (K) < 1 pM) for the receptor binding domain of the spike protein of wild-type SARS-CoV-2 and its variants of concern, including Delta and Omicron, inhibiting virus entry and infection in angiotensin converting enzyme 2 (ACE2)-bearing cells, human airway epithelial organoids and human ACE2-transgenic mice.
View Article and Find Full Text PDFSemantic cognition allows us to make sense of our varied experiences, including the words we hear and the objects we see. Contemporary accounts identify multiple interacting components that underpin semantic cognition, including diverse unimodal "spoke" systems that are integrated by a heteromodal "hub", and control processes that allow us to access weakly-encoded as well as dominant aspects of knowledge to suit the circumstances. The current study examined how these dimensions of semantic cognition might be related to whole-brain-derived components (or gradients) of connectivity.
View Article and Find Full Text PDFAlthough prediction plays an important role in language comprehension, its precise neural basis remains unclear. This fMRI study investigated whether and how semantic-category-specific and common cerebral areas are recruited in predictive semantic processing during sentence comprehension. We manipulated the semantic constraint of sentence contexts, upon which a tool-related, a building-related, or no specific category of noun is highly predictable.
View Article and Find Full Text PDFACS Pharmacol Transl Sci
December 2020
The outbreak of COVID-19 by the end of 2019 has posed serious health threats to humanity and jeopardized the global economy. However, no effective drugs are available to treat COVID-19 currently and there is a great demand to fight against it. Here, we combined computational screening and an efficient cellular pseudotyped virus system, confirming that clinical HDAC inhibitors can efficiently prevent SARS-CoV-2 and potentially be used to fight against COVID-19.
View Article and Find Full Text PDFAlthough nanomaterials have shown promising biomedical application potential, incomplete understanding of their molecular interactions with biological systems prevents their inclusion into mainstream clinical applications. Here we show that black phosphorus (BP) nanomaterials directly affect the cell cycle's centrosome machinery. BP destabilizes mitotic centrosomes by attenuating the cohesion of pericentriolar material and consequently leads to centrosome fragmentation within mitosis.
View Article and Find Full Text PDFBiochem Biophys Res Commun
September 2021
Aurora kinase A (Aurora A) plays a critical role in regulating cell mitotic progression and has been considered as a promising drug target for cancer therapy. To develop a novel molecule targeting Aurora A with high selectivity and efficacy, we designed and synthesized a pyrrole-imidazole polyamide (PIP) Hoechst conjugate, PIP-Ht, targeting to a cell-cycle regulated DNA sequence locating at the promoter of human Aurora A gene (AURKA). PIP-Ht potently suppressed AURKA promoter activities, mRNA expression and protein level, induced tumor cell cycle delay and inhibited tumor cell proliferation in vitro.
View Article and Find Full Text PDFNatural products are useful tools for biological mechanism research and drug discovery. Due to the excellent tumor cell growth inhibitory profile and sub-nanomolar potency, Coibamide A (CA), an N-methyl-stabilized depsipeptide isolated from marine cyanobacterium, has been considered as a promising lead compound for cancer treatment. However, the molecular anti-cancer mechanism of the action of CA remains unclear.
View Article and Find Full Text PDFCoibamide A () is a highly -methylated cyclodepsipeptide with low nanomolar antiproliferative activities against various cancer cell lines. In previous work, we discovered a simplified analogue, [MeAla3-MeAla6]-coibamide (), which exhibited the same inhibitory abilities as coibamide A. Herein, to reduce the whole-body toxicity and improve the solubility of , two novel peptide-drug conjugates RGD-SS-CA () and RGD-VC-CA () were designed, synthesized, and evaluated.
View Article and Find Full Text PDFChem Commun (Camb)
August 2020
A convenient and efficient strategy was developed for accessing chlorotoxin-derived bicyclic peptide-biomolecule conjugates by cyclizing fully-unprotected linear peptides with a designed tetrafunctional chemical linker. Among these peptides, bicycle-P3 bearing the N-terminal sequence of chlorotoxin shows high tumor selectivity and penetration ability, which is promising for treatment of gliomas.
View Article and Find Full Text PDFIdentification of induced pluripotent stem (iPS) progenitor cells, the iPS forming cells in early stage of reprogramming, could provide valuable information for studying the origin and underlying mechanism of iPS cells. However, it is very difficult to identify experimentally since there are no biomarkers known for early progenitor cells, and only about 6 days after reprogramming initiation, iPS cells can be experimentally determined via fluorescent probes. What is more, the ratio of progenitor cells during early reprograming period is below 5%, which is too low to capture experimentally in the early stage.
View Article and Find Full Text PDFT cells can kill tumor cells by cell surface immunological recognition, but low affinity for tumor-associated antigens could lead to T cell off-target effects. Herein, a universal T cell targeting strategy based on bio-orthogonal chemistry and glycol-metabolic engineering is introduced to enhance recognition and cytotoxicity of T cells in tumor immunotherapy. Three kinds of bicycle [6.
View Article and Find Full Text PDFThe serine/threonine kinase Polo-like kinase 1 (Plk1) plays a pivotal role in cell proliferation and has been validated as a promising anticancer drug target. However, very limited success has been achieved in clinical applications using existing Plk1 inhibitors, due to lack of sufficient specificity toward Plk1. To develop a novel Plk1 inhibitor with high selectivity and efficacy, we designed and synthesized a pyrrole-imidazole polyamide-Hoechst conjugate, PIP3, targeted to specific DNA sequence in the promoter.
View Article and Find Full Text PDFThe biological antagonism between the signaling proteins Numb and Notch has been implicated in the regulation of many developmental processes, especially in asymmetric cell division. Mechanistic studies show that Numb inactivates Notch via endocytosis and proteasomal degradation that directly reduce Notch protein levels at the cell surface. However, some aspects of how Numb antagonizes Notch remain unclear.
View Article and Find Full Text PDFBiochem Biophys Res Commun
September 2017
Autophagy is a lysosome-dependent catabolic process involving in the degradation and recycling of unnecessary or damaged proteins and organelles. Emerging evidence indicates that autophagy dysfunction is closely related to various human diseases including cancer, aging, myopathies and neurodegenerative disorders. Here, using genetic knockdown, we uncover the role of Numb, an endocytic adaptor protein, in regulating the late steps of autophagy.
View Article and Find Full Text PDFAt present, there is no specific anti-metastasis drug in HCC treatment. Drugs used for primary HCC tumors and tumor metastasis are very similar, among which cytotoxic drugs are prevalent, such as cisplatin, doxorubicin and 5-FU. The EGFR pathway plays an important role in promoting hepatocellular carcinoma (HCC) metastasis.
View Article and Find Full Text PDFTriple-negative breast cancer (TNBC), an aggressive subtype of breast cancer with higher rates of early relapse and metastasis, is frequently associated with aberrant activation of epithelial-mesenchymal transition (EMT). Nonetheless, how EMT is initiated and regulated during TNBC progression is not well understood. Here, we report that NUMB is a negative regulator of EMT in both human mammary epithelial cells and breast cancer cells.
View Article and Find Full Text PDFNumb is an endocytic protein that plays crucial roles in diverse cellular processes such as asymmetric cell division, cell migration and differentiation. However, the molecular mechanism by which Numb regulates endocytic trafficking is poorly understood. Here, we demonstrate that Numb is a docking regulator for homotypic fusion of early endosomes (EEs).
View Article and Find Full Text PDFSphingosine-1-phosphate receptor 1 (S1PR1), a G protein-coupled receptor (GPCR), controls vascular stability by stabilizing vascular endothelial (VE)-cadherin junctional localization and inhibiting vascular endothelial growth factor receptor 2 (VEGFR2) signaling. However, the molecular mechanisms that link S1PR1 signaling to intracellular effectors remain unknown. In this study, we demonstrate that the heterotrimeric G protein subfamily member Gαs, encoded by GNAS, acts as a relay mediator of S1PR1 signaling to control vascular integrity by stabilizing VE-cadherin at endothelial junctions.
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