Isoquinoline alkaloids, an important class of N‐based heterocyclic compounds, have attracted considerable attention from researchers worldwide since the early 19th century. Over the past 200 years, ...many compounds from this class were isolated, and most of them and their analogs possess various bioactivities. In this review, we survey the updated literature on bioactive alkaloids and highlight research achievements of this alkaloid class during the period of 2014–2018. We reviewed over 400 molecules with a broad range of bioactivities, including antitumor, antidiabetic and its complications, antibacterial, antifungal, antiviral, antiparasitic, insecticidal, anti‐inflammatory, antioxidant, neuroprotective, and other activities. This review should provide new indications or directions for the discovery of new and better drugs from the original naturally occurring isoquinoline alkaloids.
Salt stress can significantly affect plant growth and agricultural productivity. Receptor-like kinases (RLKs) are believed to play essential roles in plant growth, development, and responses to ...abiotic stresses. Here, we identify a receptor-like cytoplasmic kinase, salt tolerance receptor-like cytoplasmic kinase 1 (STRK1), from rice (Oryza sativa) that positively regulates salt and oxidative stress tolerance. Our results show that STRK1 anchors and interacts with CatC at the plasma membrane via palmitoylation. CatC is phosphorylated mainly at Tyr-210 and is activated by STRK1. The phosphorylation mimic form CatCY210D exhibits higher catalase activity both in vitro and in planta, and salt stress enhances STRK1-mediated tyrosine phosphorylation on CatC. Compared with wild-type plants, STRK1-overexpressing plants exhibited higher catalase activity and lower accumulation of H2O2 as well as higher tolerance to salt and oxidative stress. Our findings demonstrate that STRK1 improves salt and oxidative tolerance by phosphorylating and activating CatC and thereby regulating H2O2 homeostasis. Moreover, overexpression of STRK1 in rice not only improved growth at the seedling stage but also markedly limited the grain yield loss under salt stress conditions. Together, these results offer an opportunity to improve rice grain yield under salt stress.
Autophagy is a degradative pathway that delivers cellular components to the lysosome for degradation. The role of autophagy in cell differentiation is poorly understood. Here we show that CaMKII can ...directly phosphorylate Beclin 1 at Ser90 to promote K63-linked ubiquitination of Beclin 1 and activation of autophagy. Meanwhile, CaMKII can also promote K63-linked ubiquitination of inhibitor of differentiation 1/2 (Id-1/2) by catalyzing phosphorylation of Id proteins and recruiting TRAF-6. Ubiquitinated Id-1/Id-2 can then bind to p62 and be transported to autolysosomes for degradation. Id degradation promotes the differentiation of neuroblastoma cells and reduces the proportion of stem-like cells. Our study proposes a mechanism by which autophagic degradation of Id proteins can regulate cell differentiation. This suggests that targeting of CaMKII and the regulation of autophagic degradation of Id may be an effective therapeutic strategy to induce cell differentiation in neuroblastoma.
Abstract
Most triple-negative breast cancer (TNBC) patients fail to respond to T cell-mediated immunotherapies. Unfortunately, the molecular determinants are still poorly understood. Breast cancer is ...the disease genetically linked to a deficiency in autophagy. Here, we show that autophagy defects in TNBC cells inhibit T cell-mediated tumour killing in vitro and in vivo. Mechanistically, we identify Tenascin-C as a candidate for autophagy deficiency-mediated immunosuppression, in which Tenascin-C is Lys63-ubiquitinated by Skp2, particularly at Lys942 and Lys1882, thus promoting its recognition by p62 and leading to its selective autophagic degradation. High Tenascin-C expression is associated with poor prognosis and inversely correlated with LC3B expression and CD8
+
T cells in TNBC patients. More importantly, inhibition of Tenascin-C in autophagy-impaired TNBC cells sensitizes T cell-mediated tumour killing and improves antitumour effects of single anti-PD1/PDL1 therapy. Our results provide a potential strategy for targeting TNBC with the combination of Tenascin-C blockade and immune checkpoint inhibitors.
The accumulation of lipid peroxides is recognized as a determinant of the occurrence of ferroptosis. However, the sensors and amplifying process of lipid peroxidation linked to ferroptosis remain ...obscure. Here we identify PKCβII as a critical contributor of ferroptosis through independent genome-wide CRISPR-Cas9 and kinase inhibitor library screening. Our results show that PKCβII senses the initial lipid peroxides and amplifies lipid peroxidation linked to ferroptosis through phosphorylation and activation of ACSL4. Lipidomics analysis shows that activated ACSL4 catalyses polyunsaturated fatty acid-containing lipid biosynthesis and promotes the accumulation of lipid peroxidation products, leading to ferroptosis. Attenuation of the PKCβII-ACSL4 pathway effectively blocks ferroptosis in vitro and impairs ferroptosis-associated cancer immunotherapy in vivo. Our results identify PKCβII as a sensor of lipid peroxidation, and the lipid peroxidation-PKCβII-ACSL4 positive-feedback axis may provide potential targets for ferroptosis-associated disease treatment.
Most patients with triple negative breast cancer (TNBC) do not respond to anti-PD1/PDL1 immunotherapy, indicating the necessity to explore immune checkpoint targets. B7H3 is a highly glycosylated ...protein. However, the mechanisms of B7H3 glycosylation regulation and whether the sugar moiety contributes to immunosuppression are unclear. Here, we identify aberrant B7H3 glycosylation and show that N-glycosylation of B7H3 at NXT motif sites is responsible for its protein stability and immunosuppression in TNBC tumors. The fucosyltransferase FUT8 catalyzes B7H3 core fucosylation at N-glycans to maintain its high expression. Knockdown of FUT8 rescues glycosylated B7H3-mediated immunosuppressive function in TNBC cells. Abnormal B7H3 glycosylation mediated by FUT8 overexpression can be physiologically important and clinically relevant in patients with TNBC. Notably, the combination of core fucosylation inhibitor 2F-Fuc and anti-PDL1 results in enhanced therapeutic efficacy in B7H3-positive TNBC tumors. These findings suggest that targeting the FUT8-B7H3 axis might be a promising strategy for improving anti-tumor immune responses in patients with TNBC.
Although 5-methylcytosine (m
C) is a widespread modification in RNAs, its regulation and biological role in pathological conditions (such as cancer) remain unknown. Here, we provide the ...single-nucleotide resolution landscape of messenger RNA m
C modifications in human urothelial carcinoma of the bladder (UCB). We identify numerous oncogene RNAs with hypermethylated m
C sites causally linked to their upregulation in UCBs and further demonstrate YBX1 as an m
C 'reader' recognizing m
C-modified mRNAs through the indole ring of W65 in its cold-shock domain. YBX1 maintains the stability of its target mRNA by recruiting ELAVL1. Moreover, NSUN2 and YBX1 are demonstrated to drive UCB pathogenesis by targeting the m
C methylation site in the HDGF 3' untranslated region. Clinically, a high coexpression of NUSN2, YBX1 and HDGF predicts the poorest survival. Our findings reveal an unprecedented mechanism of RNA m
C-regulated oncogene activation, providing a potential therapeutic strategy for UCB.
Silver halide-based structures have been attracting great interest as efficient visible-light-driven photocatalysts towards the photodegradation of organic pollutants, and those studies focusing on ...their morphology-dependent catalytic performances have received particular attention. While great advancements in this regard have been witnessed in the past few years with respect to AgCl- and AgBr-based photocatalysts, relevant explorations concerning AgI-based species are relatively rare, even though the excellent durability of AgI-based structures renders them attractive candidates for potential photocatalytic uses. By means of chemical reactions between AgNO
and tetramethylammonium iodide (TMAI), and AgNO
and tetrabutylammonium iodide (TBAI), we herein report that AgI structures with a sheet-like and a truncated-dodecahedron-like morphology, respectively, could be controllably synthesized via a surfactant-assisted fabrication protocol. In our synthesis systems, AgNO
works as the silver source, while the TMAI and TBAI surfactants serve not only as an iodine source but also as a directing reagent for controllable fabrication. It has been demonstrated that our AgI structures could work as visible-light-energized photocatalysts towards the photodegradation of methyl orange. We find that compared to their sheet-like counterparts, the truncated-dodecahedron-like AgI architectures exhibit substantially boosted catalytic performances. Moreover, we disclose that our truncated-dodecahedron-like AgI-based species could display excellent photocatalytic stability, wherein their catalytic reactivity displays only trivial fluctuations under visible-light irradiation even after the photoreactions have been repeated 22 times continuously. Our work might not only introduce a facile protocol for the controllable synthesis of AgI structures but also pave an avenue for facile enhancement of their catalytic performances via morphology alterations.
Wireless sensor network (WSN) in the Internet of Things consists of a large number of nodes. The proposal of compressive sensing technology provides a novel way for data aggregation in WSN. Based on ...the clustering structure of WSN, a kind of effective data aggregating method based on compressive sensing is proposed in this paper. The aggregating process is divided into two parts: in the cluster, the sink node sets the corresponding seed vector based on the distribution of network and then sends it to each cluster head. Cluster head can generate corresponding own random spacing sparse matrix based on its received seed vector and collect data through compressive sensing technology. Among clusters, clusters forward measurement values to the sink node along multi-hop routing tree. Performance analysis and comparison with the relative methods show that our method is effective and superior to other methods regardless of intra-cluster or inter-cluster on the total energy consumption of network.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Microvesicles (MVs) derived from human mesenchymal stem cells (MSC MVs) were demonstrated to ameliorate inflammation in lungs. We have found their content of mRNA for keratinocyte growth factor was ...partly involved in their therapeutic effects. As MSC MVs also contained a substantial quantity of angiopoietin‐1 (Ang‐1) mRNA, which plays an essential role in vascular stabilization and resolving inflammation, we hypothesized that Ang‐1 mRNA might similarly account for a part of their therapeutic effects. We downregulated Ang‐1 mRNA expression in MVs, using a lentivirus vector carrying Ang‐1 short hairpin RNA to transfect MSCs. A mouse model of lipopolysaccharide induced acute lung injury (ALI) was used in vivo. We also studied in vitro interactions between Ang‐1 mRNA deficient MVs on macrophages and human lung microvascular endothelial cells. Compared with negative control, Ang‐1 mRNA deficient MVs increased the influx of neutrophils and macrophage inflammatory protein‐2 levels in bronchoalveolar lavage fluid by 136% and 105%, respectively, suggesting a deteriorative lung inflammation and a failure to restore pulmonary capillary permeability assessed by Evan's blue dye and bronchoalveolar lavage albumin level. In vitro, the addition of Ang‐1 mRNA deficient MVs failed to maintain the integrity of endotoxin‐stimulated microvascular endothelial cells and abrogated the decrease in tumor necrosis factor‐α level and the increase in interleukin‐10 level mediated by negative control in RAW 264.7 cells. In summary, the therapeutic effects of MVs in ALI, and their immunomodulatory properties on macrophages were partly mediated through their content of Ang‐1 mRNA. Stem Cells 2017;35:1849–1859
MSC MVs improved lung injury as assessed by histology at 48 hours. H&E staining of lung section demonstrated a reduction in inflammatory cell influx, blood, edema, airspace congestion, and wall thickening (scale bars = 200μm). Ang‐1 SiRNA MSC MV significantly eliminated the beneficial effects of MSC MVs.
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