Heart disease is the leading cause of death worldwide. A key pathogenic factor in the development of lethal heart failure is loss of terminally differentiated cardiomyocytes. However, mechanisms of ...cardiomyocyte death remain unclear. Here, we discovered and demonstrated that ferroptosis, a programmed iron-dependent cell death, as a mechanism in murine models of doxorubicin (DOX)- and ischemia/reperfusion (I/R)-induced cardiomyopathy. In canonical apoptosis and/or necroptosis-defective Ripk3−/−, Mlkl−/−, or Fadd−/−Mlkl−/− mice, DOX-treated cardiomyocytes showed features of typical ferroptotic cell death. Consistently, compared with dexrazoxane, the only FDA-approved drug for treating DOX-induced cardiotoxicity, inhibition of ferroptosis by ferrostatin-1 significantly reduced DOX cardiomyopathy. RNA-sequencing results revealed that heme oxygenase-1 (Hmox1) was significantly up-regulated in DOX-treated murine hearts. Administering DOX to mice induced cardiomyopathy with a rapid, systemic accumulation of nonheme iron via heme degradation by Nrf2-mediated upregulation of Hmox1, which effect was abolished in Nrf2-deficent mice. Conversely, zinc protoporphyrin IX, an Hmox1 antagonist, protected the DOX-treated mice, suggesting free iron released on heme degradation is necessary and sufficient to induce cardiac injury. Given that ferroptosis is driven by damage to lipid membranes, we further investigated and found that excess free iron accumulated inmitochondria and caused lipid peroxidation on its membrane. Mitochondria-targeted antioxidant MitoTEMPO significantly rescued DOX cardiomyopathy, supporting oxidative damage of mitochondria as a major mechanism in ferroptosis-induced heart damage. Importantly, ferrostatin-1 and iron chelation also ameliorated heart failure induced by both acute and chronic I/R in mice. These findings highlight that targeting ferroptosis serves as a cardioprotective strategy for cardiomyopathy prevention.
The mechanism by which tumor-associated macrophages (TAMs) affect cancer progression is not fully understood. This study developed a microfluidic-based co-culture device to mimic the tumor ...microenvironment to assess TAM effects on invasion and metastasis in NSCLC. The results showed lung carcinoma cells could cause macrophages to show the M2 (a TAM-like) phenotype, and these M2 macrophages promoted lung cancer cell EMT and invasion. Proteomic analysis by the iTRAQ quantitation strategy and GO ontology of the cancer cells indicated that αB-Crystallin (CRYAB) might be involved in this process. Further, we confirmed the role of CRYAB in cancer invasion and metastasis through cell and animal experiments, as well as human cancer tissue assessment. Overall, we demonstrated that M2 macrophages promote malignancy in lung cancer through the EMT by upregulating CRYAB expression and activating the ERK1/2/Fra-1/slug signaling pathway.
Glycosphingolipids (GSLs) are ubiquitous glycoconjugates present on the cell membrane; they play significant roles in many bioprocesses such as cell adhesion, embryonic development, signal ...transduction and carcinogenesis. Analyzing such amphiphilic molecules is a major challenge in the field of glycosphingolipidomics. We provide a step-by-step protocol that uses a lectin microarray to analyze GSL glycans from cultured cells. The procedure describes (i) extraction of GSLs from cell pellets, (ii) N-monodeacylation using sphingolipid ceramide N-deacylase digestion to form lyso-GSLs, (iii) fluorescence labeling at the newly exposed amine group, (iv) preparation of a lectin microarray, (v) GSL-glycan analysis by a lectin microarray, (vi) complementary mass spectrometry analysis and (vii) data acquisition and analysis. This method is high-throughput, low cost and easy to conduct, and it provides detailed information about glycan linkages. This protocol takes ~10 d.
The blood–brain barrier (BBB) establishes a protective interface between the central neuronal system and peripheral blood circulation and is crucial for homeostasis of the CNS. BBB formation ...startswhen the endothelial cells (ECs) invade the CNS and pericytes are recruited to the nascent vessels during embryogenesis. Despite the essential function of pericyte–EC interaction during BBB development, the molecular mechanisms coordinating the pericyte–EC behavior and communication remain incompletely understood. Here, we report a single cell receptor, CD146, that presents dynamic expression patterns in the cerebrovasculature at the stages of BBB induction and maturation, coordinates the interplay of ECs and pericytes, and orchestrates BBB development spatiotemporally. In mouse brain, CD146 is first expressed in the cerebrovascular ECs of immature capillaries without pericyte coverage; with increased coverage of pericytes, CD146 could only be detected in pericytes, but not in cerebrovascular ECs. Specific deletion of Cd146 in mice ECs resulted in reduced brain endothelial claudin-5 expression and BBB breakdown. By analyzing mice with specific deletion of Cd146 in pericytes, which have defects in pericyte coverage and BBB integrity, we demonstrate that CD146 functions as a coreceptor of PDGF receptor-β to mediate pericyte recruitment to cerebrovascular ECs. Moreover, we found that the attached pericytes in turn down-regulate endothelial CD146 by secreting TGF-β1 to promote further BBB maturation. These results reveal that the dynamic expression of CD146 controls the behavior of ECs and pericytes, thereby coordinating the formation of a mature and stable BBB.
Small ribosomal subunits are co-transcriptionally assembled on the nascent precursor rRNA in Saccharomyces cerevisiae. It is unknown how the highly intertwined structure of 60S large ribosomal ...subunits is initially formed. Here, we affinity purified and analyzed a series of pre-60S particles assembled in vivo on plasmid-encoded pre-rRNA fragments of increasing lengths, revealing a spatiotemporal assembly map for 34 trans-acting assembly factors (AFs), 30 ribosomal proteins and 5S rRNA. The gradual association of AFs and ribosomal proteins with the pre-rRNA fragments strongly supports that the pre-60S is co-transcriptionally, rather than post-transcriptionally, assembled. The internal and external transcribed spacers ITS1, ITS2 and 3΄ ETS in pre-rRNA must be processed in pre-60S. We show that the processing machineries for ITS1 and ITS2 are primarily recruited by the 5΄ and 3΄ halves of pre-27S RNA, respectively. Nevertheless, processing of both ITS1 and ITS2 requires a complete 25S region. The 3΄ ETS plays a minor role in ribosome assembly, but is important for efficient rRNA processing and ribosome maturation. We also identified a distinct pre-60S state occurring before ITS2 processing. Our data reveal the elusive co-transcriptional assembly pathway of large ribosomal subunit.
•Large Ashele copper–zinc deposit is a typical VMS deposit.•There are differences in the ore-forming fluids of the stratiform orebody and stockwork orebody.•The sulfur was derived from the seawater ...sulfate and host volcanic rocks, and ore-forming fluids were derived from deep circulation of seawater, and mixed with minor magmatic fluids.
The Altay orogenic belt of Kazakhstan and China incorporates one of the world-class volcanogenic massive sulfide (VMS) polymetallic metallogenic belt. More than 12 large and superlarge VMS deposits have been found in this belt. The Ashele Basin is located at the western end of the Chinese Altay bordering Kazakhstan and hosts the large Ashele copper–zinc deposit, which is a typical VMS deposit and the largest one in this basin. The principal orebodies are stratabound and located between basalt and tuff units in the Ashele Formation. The mineralization has a two-layered structure that consists of an upper stratiform, concordant, massive Cu–Zn (or barite) orebody, and a lower veinlet–disseminated and stockwork Cu (or Cu–Pb–Zn–Ag) orebody associated with silicic alteration. Several exhalative rocks, such as barite, hematitic jasper, pyrite and silicified units also occur.
Here we investigate the ore-forming fluids of the exhalative–sedimentary units including jaspilte, stratiform barite and Cu–Zn orebodies which carry fluid inclusions that show homogenization temperatures of 100–410 °C, with two peaks around 230 and 150 °C, and low salinity (clustering between 2 and 8 wt% NaCl equiv), corresponding to NaCl–H2O fluids. The ore-forming fluids of the vein orebody and silicified zones are characterized by low to medium temperature (peak homogenization temperatures between 120 and 280 °C), low to medium salinity (0.7–12.3 wt% NaCl equiv), and H2O–CO2 (±CH4/N2)–NaCl fluids. The δ34S values of barite associated with the stratiform barite orebody range from 20.4‰ to 21.4‰, indicating that the sulfur was derived from the seawater. The sulfur isotope values of sulfide (−3.7‰ to 7.7‰ with a mean of 3.1‰) are similar to those of VMS deposits from other parts of the world. The host volcanic rocks are inferred to be the major source from which the mineralizing fluid leached the ore-forming elements. The 3He/4He ratios of fluid inclusions in pyrite are in the range of 0.136–0.260 (R/Ra), broadly similar to the helium ratios of the crust. The 40Ar/36Ar ratios range from 394 to 9515, and are higher than those of atmospheric argon. The 40Ar/4He ratios of the ore fluids range from 0.002 to 0.064 with a mean of 0.034. The helium and argon isotope compositions of fluid inclusions suggest that the ore fluids of the Ashele deposit were mainly derived from the crust and were mixed with a minor amount of mantle component. The δ18OSMOW values of quartz from the silicified zones and vein orebody range from 8.3‰ to 11.1‰, with corresponding δ18Ofluid values of −4.45‰ to 2.24‰, whereas the δD values of fluid inclusions are between −140‰ and −90‰. The δ18OSMOW values of barite from the stratiform barite orebody range from 7.7‰ to 9.1‰, with corresponding δ18Ofluid values of –3.03‰ to 1.79‰, with δD values of fluid inclusions showing a range of –162‰ and –135‰. The combined isotopic data (H–O and He–Ar) suggest that the ore-forming fluids of the Ashele deposit were mainly derived from deep circulation of seawater and mixed with magmatic fluids. The decrease in temperature and pressure, water–rock exchange, and changes in the composition of ore fluids played important roles in the ore-forming processes of the Ashele Cu–Zn deposit.
Programmed -1 ribosomal frameshifting (-1PRF) is a widely used translation recoding mechanism. HIV-1 expresses Gag-Pol protein from the Gag-coding mRNA through -1PRF, and the ratio of Gag to Gag-Pol ...is strictly maintained for efficient viral replication. Here, we report that the interferon-stimulated gene product C19orf66 (herein named Shiftless) is a host factor that inhibits the -1PRF of HIV-1. Shiftless (SFL) also inhibited the -1PRF of a variety of mRNAs from both viruses and cellular genes. SFL interacted with the -1PRF signal of target mRNA and translating ribosomes and caused premature translation termination at the frameshifting site. Downregulation of translation release factor eRF3 or eRF1 reduced SFL-mediated premature translation termination. We propose that SFL binding to target mRNA and the translating ribosome interferes with the frameshifting process. These findings identify SFL as a broad-spectrum inhibitor of -1PRF and help to further elucidate the mechanisms of -1PRF.
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•Shiftless is a broad-spectrum inhibitor of programmed -1 ribosomal frameshifting•Shiftless interacts with the frameshifting signal RNA and translating ribosomes•Shiftless causes premature translation termination at the frameshifting site•eRF1 and eRF3 are required for Shiftless-mediated translation termination
A host HIV restriction factor inhibits programmed ribosomal frameshifting via direct interaction with ribosomes and frameshifting RNA to cause premature translation termination.
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•The metallic ore deposits in the Altay Mountains occur mainly within four regions.•We recognize seven types of metallic ore deposits.•The timing of the metallic mineralization can be ...divided into four epochs.•The metallic deposits developed in various tectonic settings.
The Altay Mountains within the Xinjiang region of northwestern China hosts major metallic ore deposits. Here we review the geological characteristics, metallogenic features and tectonic settings of these deposits. The metallic ore deposits in the Altay Mountains occur mainly within four regions: North Altay, Central Altay, South Altay and Erqis. We recognize seven types of metallic ore deposits in the Altay Mountains: VMS, submarine volcanogenic iron, magmatic, skarn, pegmatite, hydrothermal vein (Cu–Zn, Fe) and orogenic gold. Among these types, the VMS, pegmatite, orogenic gold and skarn deposits are the most common. Most of the rare metal pegmatite deposits are distributed in Central Altay, with only a few in South Altay. The VMS, submarine volcanogenic type iron and skarn-type deposits are distributed in South Altay, whereas the orogenic-type gold deposits are distributed in the Erqis Fault belt. The hydrothermal vein-type deposits occur in the Erqis Fault belt and Chonghu’er Basin in South Altay. Magmatic-type deposits are mostly in the Erqis Fault belt and Central Altay. Based on isotopic age data, the VMS, submarine volcanogenic-type Fe and skarn-type Cu, Pb, Zn, Fe mineralization occurred during Early–Middle Devonian (∼410–377Ma), orogenic-type Au, magmatic-type Cu–Ni, and a small number of skarn-type Fe, hydrothermal vein-type Cu–Zn, pegmatite-type rare-metal deposits in Early–Middle Permian (293–261Ma), pegmatite-type rare-metal deposits, few skarn-type Fe deposit in Early–Middle Triassic (248–232Ma), and dominantly represented by pegmatite-type rare-metal deposits in Late Triassic–Early Jurassic (223–180Ma). The metallic ore deposits in the Altay Mountains formed in various tectonic settings, such as the Early–Middle Devonian continental arc and oceanic island arc, Early–Middle Permian post-collisional extensional setting, and Triassic–Early Jurassic intracontinental setting.
The Wulong lode gold deposit is located in the Liaoning Province, northeast part of North China Craton. Gold ore bodies are mainly hosted in the Late Jurassic granite and structurally controlled by ...northeast-trending faults. Gold occurs in disseminated and auriferous quartz-sulfide veins and veinlets within hydrothermally altered rocks. Mineralization can be divided into three stages: (1) quartz-pyrite stage, (2) quartz-polymetallic sulfides stage, and (3) quartz-carbonate stage. Gold formed mainly in the middle stage. Quartz formed in the two earlier stages contains three compositional types of fluid inclusions, i.e., pure CO2, CO2-H2O and NaCl-H2O, but the late-stage minerals only contain NaCl-H2O inclusions. The inclusions in quartz formed in the early, main, and late stages yield total homogenization temperatures of 317-383 °C, 260-380 °C and 159-234 °C, respectively, with salinities of 5.14-9.44, 2.95-6.20, 1.23-4.34 wt% NaCl equivalent, respectively. Trapping pressures estimated from CO2-H2O inclusions are 200-390 MPa in the main stage. Fluid boiling and immiscibility caused rapid precipitation of sulfides and gold. Through immiscibility and inflow of meteoric water, the ore-forming fluid system evolved from CO2-rich to CO2-poor in composition, and from magmatic to meteoric, as indicated by δ18Owater values (4.5 ppm-7.3 ppm). The carbon (-12.2 ppm to -11.5 ppm), sulfur (0.9 ppm-2.6 ppm), and lead isotope (207Pb/204Pb of 15.606-15.618) compositions suggest the host rocks to be a significant source of ore metals. Integrating the data obtained from the studies including regional geology, ore geology, fluid inclusion, and C-H-O-S-Pb isotope geochemistry, we conclude that the Wulong deposit is a decratonization gold deposit formed during lithospheric thinning associated with destruction of the North China Craton triggered by the subduction of the Paleo-Pacific Oceanic plate in the Early Cretaceous.
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•Zircon U-Pb age show the age of 246 ± 1.7 Ma for the biotite granite in the Xiaobaishitou W-(Mo) ore district.•Petrography and geochemistry show the biotite granite is I-type ...granite.•Geochemical and isotopic data indicate they the biotite granite likely derived from both mantle- and crustal-derived magmas.•Triassic granites of eastern Tianshan were likely formed in an intra-continental setting.
The Xiaobaishitou W-(Mo) deposit (Central Tianshan Massif, eastern Tianshan, northwestern China) is a skarn-type tungsten-molybdenum deposit associated with a biotite granite intruding the Mesoproterozoic Kawabulag Group. Here we present the results from zircon U-Pb geochronology, whole-rock geochemical, and Sr-Nd-Hf isotopic analyses of the biotite granite. Zircon U-Pb dating shows that the biotite granite crystallized at 246.4 ± 1.7 Ma, suggesting that the Xiaobaishitou deposit formed during the Early Triassic. Bulk rock geochemistry shows that the biotite granite has high Si, Rb, K, and light rare earth element contents, but low Ba, Nb, Sr, P, and Ti. Moreover, the rocks have mostly positive εHf(t) values (−0.06 to 4.60), negative εNd(t) values (−3.87 to −2.40), and corresponding Hf isotope TDM2 ages (1.29–1.71 Ga) and Nd isotope TDM2 ages (1.23–1.36 Ga). These geochemical and isotopic data imply that the Xiaobaishitou biotite granite derived from both mantle- and crustal-derived magmas. By comparison of the Xiaobaishitou biotite granite to nearby granites from the Donggebi and Baishan Mo deposits, we show that Triassic granites of the eastern Tianshan likely formed in an intra-continental tectonic setting, and magmatism and metallogenesis were probably associated with regional extension.
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