The Sarsuk polymetallic Au deposit is located in the Devonian volcano-sedimentary Ashele Basin of the Altay Orogenic Belt (AOB), Xinjiang. Mineralization in the deposit is confined to an area of 400m ...long and 50–120m wide, and occurs as dense massive, banded, disseminated, stockwork, and veinlet ore structures. Exhalative sedimentary, subvolcanic hydrothermal, and supergene periods have been distinguished. Although syn-depositional ores can be found, the main orebodies from this period have been eroded. Thus, the orebodies being mined are hosted mainly in a rhyolite porphyry subvolcanic intrusion within the volcanic conduit of a hydrothermal system. Electron microprobe analysis of the main ore minerals indicates that pyrite is the main Au-bearing mineral. The Au occurs mainly as either inclusions or in fissures in the form of tellurides, and is closely associated with Ag. Zn/Fe ratios of sphalerite vary from 11.37 to 251.36, with an average of 96.65, and the formation temperatures of chlorites are 155–206°C, with an average of 175°C. The compositions of sphalerite and chlorite indicate that the main mineralization occurred in a low- to moderate-temperature environment. Homogenization temperatures of fluid inclusions from ores of the main mineralization stage vary generally from 130°C to 390°C, with peaks at 140°C, 190°C, and 310°C. Their corresponding salinities range from 3.0 to 10.0wt.% NaCl equivalent, with densities from 0.56 to 1.03g/cm3. The main mineralizing fluid of the deposit is characterized by high–low temperatures, moderate–low salinities, and moderate–low densities. The 3He/4He ratios of fluid inclusions in pyrite are 0.02 to 0.44 Ra, and the percentage of mantle-derived He ranges from 0.06% to 7.45%. 40Ar/36Ar ratios range from 319.6 to 458.5, and the percentage of 40Ar* varies from 7.53% to 35.55%. Both fluid characteristics and He and Ar isotope compositions suggest that the ore-forming fluids were a mixture of magmatic fluid and seawater. The CO2-rich fluids in the ores suggest that boiling occurred. The mixing of a high-temperature and high-pressure magmatic fluid with deeply circulating seawater caused a decrease in temperature, and phase separation in the ore-forming fluids. Thus, the precipitation of the most economically important ore materials was the result of this mixing process.
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•The Au–Cu–Pb–Zn mineralization of the Sarsuk polymetallic Au deposit formed from a subvolcanic hydrothermal system.•The main mineralization occurred in a low- to moderate-temperature environment.•The ore-forming fluids were a mixture of magmatic fluid and deeply circulating seawater.•The precipitation of the most economically important metallogenic materials was the result of the mixing process.
A collation of previous ages and our new results show that extensive magmatism occurred from 350 to 270 Ma in the Aqishan–Yamansu–Shaquanzi belt, with a peak of 335–305 Ma. During 334–273 Ma, ...volcanic–sedimentary exhalative processes, magmatic-hydrothermal metasomatism and skarnization caused by intrusions, which occurred at different stages, resulted in Fe-dominated and other polymetallic mineralization in the eastern part of this belt.
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•The peak of magmatic activities in the Aqishan–Yamansu–Shaquanzi belt is proposed.•Fe-(Cu) polymetallic mineralization resulted from different metallogenesis.•Several dominated metallogenic stages in the eastern part of the belt are proposed.
The Aqishan–Yamansu–Shaquanzi belt is a well-known Fe–Cu–Au metallogenic belt located in the Central Asian Orogenic Belt, NW China. Numerous Fe-rich ores as well as polymetallic mineralization (including Cu, Pb, Zn, and Co) and related magmatic–hydrothermal alteration are hosted in volcanic rocks, especially those in the eastern part of this metallogenic belt. The complex geology of the belt and the divergent geochronological data obtained by different investigators and analytical methods have led to contrasting opinions on the deposit types and metallogenesis of the belt. The present study focuses on the Shaquanzi, Yamansu, and Heifengshan Fe–(Cu) polymetallic deposits in the eastern part of the belt. These deposits display Fe-dominated metallogenesis related to volcanic–sedimentary exhalative processes and polymetallic metallogenesis related to volcanic–hydrothermal metasomatism and skarnization caused by subsequent intrusion processes. The Shaquanzi, Yamansu, and Heifengshan deposits have undergone multiple periods of metallogenesis and contain late Fe–Cu–Pb–Mo, Fe–Cu–Zn–(Co), and Fe–Cu mineralization, respectively. Using zircon U–Pb dating by laser-ablation–multi-collector–inductively coupled plasma–mass spectrometry, two rhyolite samples (at the base and lower-middle part of the Tugutubulak Formation) and a basaltic andesite and a diorite dyke in the Shaquanzi ore district yield concordant ages of 327.9 ± 2.6 Ma (mean square of weighted deviates or MSWD = 0.015), 327.8 ± 1.4 Ma (MSWD = 1.03), 285.9 ± 2.0 Ma (MSWD = 0.81), and 276.3 ± 1.4 Ma (MSWD = 0.21), respectively. Basaltic andesite from the Upper Yamansu Formation in the Yamansu deposit area yields a concordant age of 327.6 ± 6.4 Ma (MSWD = 0.54), whereas rhyolite, diorite dyke, and granite stock from the Heifengshan deposit give concordant ages of 285.7 ± 1.3 Ma (MSWD = 0.01), 273.7 ± 1.6 Ma (MSWD = 1.2), and 274.4 ± 2.5 Ma (MSWD = 0.20), respectively. Hydrothermal molybdenite in the Shaquanzi deposit yields a weighted mean Re–Os age of 314.6 ± 1.7 Ma (MSWD = 0.29) and an isochron age of 316 ± 6 Ma (MSWD = 0.46). A collation of previously reported ages and our new age data show that extensive magmatism occurred during the Carboniferous–early Permian (ca. 350–270 Ma) in the Aqishan–Yamansu–Shaquanzi belt, with a peak period between ca. 335 and ca. 305 Ma. The Yamansu Formation and Tugutubulak Formation volcanic rocks formed at ca. 348–334 Ma (early Carboniferous) and between ca. 328 and ca. 303 Ma (late early Carboniferous to late Carboniferous), respectively. In the eastern part of the belt, Fe-dominated mineralization resulting from volcanic–sedimentary exhalative processes (e.g., ca. 334, ca. 322, and ca. 286 Ma) and polymetallic mineralization resulting from volcanic–hydrothermal metasomatism (e.g., ca. 334–323 Ma), as well as skarnization and magmtic-hydrothermal caused by intrusions occurred at different stages (e.g., ca. 322–316, ca. 299, and ca. 274 Ma), leading to the superimposition of polymetallic mineralization between ca. 334 and ca. 273 Ma.
The Huangtan (including Jinling) Au–Cu–Zn deposit is an auriferous volcanogenic massive sulfide (VMS) deposit discovered in East Tianshan, Central Asian Orogenic Belt. The deposit is hosted in ...volcanic breccia and tuff of the Silurian Hongliuxia Formation. The ore bodies consist of concordant massive sulfide lenses and discordant sulfide veins. Chalcopyrite Re–Os dating constrained the age of mineralization in the Huangtan deposit at 432 Ma. Quartz and barite host abundant liquid-rich, liquid-only and minor vapor-rich aqueous fluid inclusions. The fluid inclusions in barite from the exhalative–sedimentary units mainly have homogenization temperatures at 140–260 °C, and calculated salinities of 3–9 wt% NaCl equiv.; Those values are at 120–300 °C, and 1–9 wt% NaCl equiv. for varieties in quartz from the vein ores and alteration assemblages. Fluid inclusions extract from pyrite have
3
He/
4
He ratios of 0.929–1.374 Ra,
40
Ar/
36
Ar of 388–520, and
40
Ar/
4
He of 0.355–0.836. The quartz and barite yielded δ
18
O values of 7.4‰ to 10.1‰ and the δD
V-SMOW
values of the fluid inclusions in the quartz and barite range from − 69 to − 42‰. The He–Ar and H–O isotopes imply that the ore-forming fluids were derived from a magmatic source with the addition of deeply circulating seawater. The δ
34
S
V-CDT
values of pyrite and chalcopyrite range from − 2.0 to 1.5‰, and those of barite samples range from 24.1 to 24.8‰, which indicates that sulfur was derived from magmatic sulfur, and was subjected to fractionation between sulfide and sulfate. Linked to the ore geology, geochronology data, isotope compositions and fluid inclusions obtained in this study with those of previously published adjacent VMS deposits in the Kalatag area suggest that the Huangtan deposit and adjacent VMS deposits formed in the same metallogenic system.
•Ashele Cu–Zn deposit is a VMS deposit.•Sarsuk polymetallic Au deposit is associated with rhyolite porphyry.•The Ashele Formation yield U–Pb ages of 375–402Ma.•The exhalative–sedimentary period of ...mineralization formed at 388Ma.•Au–Cu–Pb–Zn and Cu mineralization formed at 379–382Ma.
The Altay orogenic belt of Kazakhstan hosts a world-class polymetallic copper volcanogenic massive sulfide (VMS) metallogenic belt, and the eastern margin of this belt extends into the southern Chinese Altay. The Ashele Basin is located at the western end of the Chinese Altay and borders Kazakhstan. The basin hosts the large Ashele copper–zinc deposit, which is a typical VMS deposit and the largest deposit in the Ashele Basin, and it hosts the subvolcanic-hosted medium-sized Sarsuk polymetallic gold deposit. Both of these deposits are hosted in the Ashele Formation volcanic sequence. The Ashele copper–zinc orebodies are stratabound orebodies located between basalt and tuff units, and were formed during exhalative sediment deposition; in comparison, the Sarsuk gold–copper–lead–zinc orebodies are hosted by rhyolite porphyry that contains disseminated, veinlet, and veinlet–stockwork ore that formed during intrusion of the rhyolite porphyry. This study presents new zircon LA–MC–ICP–MS U–Pb analyses of six volcanic and subvolcanic units, and dikes associated with the Sarsuk and Ashele deposits. The ore-bearing rhyolite porphyry, diabase dike, basalt, tuff, and dacite porphyry samples analyzed during this study yielded ages of 382.0–382.8, 381.7, 388.2, 387.0, and 379.4Ma, respectively. These data indicate that the Ashele Formation formed during the Early–Mid-Devonian (375–402Ma), whereas the Ashele copper–zinc deposit formed during the Middle Devonian (388–387Ma) and the Sarsuk polymetallic copper–gold deposit formed during the latest Middle Devonian (382Ma). Inherited zircons within the six samples analyzed during this study yielded U–Pb ages of 618–2294Ma, suggesting the presence of Precambrian crystalline basement within the Altay orogenic belt.
The outer membrane (OM) of Gram-negative bacteria is an evolving antibiotic barrier composed of a glycerophospholipid (GP) inner leaflet and a lipopolysaccharide (LPS) outer leaflet. The ...two-component regulatory system CrrAB has only recently been reported to confer high-level polymyxin resistance and virulence in Klebsiella pneumoniae. Mutations in crrB have been shown to lead to the modification of the lipid A moiety of LPS through CrrAB activation. However, functions of CrrAB activation in the regulation of other lipids are unclear. Work here demonstrates that CrrAB activation not only stimulates LPS modification but also regulates synthesis of acyl-glycerophosphoglycerols (acyl-PGs), a lipid species with undefined functions and biosynthesis. Among all possible modulators of acyl-PG identified from proteomic data, we found expression of lipid A palmitoyltransferase (PagP) was significantly upregulated in the crrB mutant. Furthermore, comparative lipidomics showed that most of the increasing acyl-PG activated by CrrAB was decreased after pagP knockout with CRISPR-Cas9. These results suggest that PagP also transfers a palmitate chain from GPs to PGs, generating acyl-PGs. Further investigation revealed that PagP mainly regulates the GP contents within the OM, leading to an increased ratio of acyl-PG to PG species and improving OM hydrophobicity, which may contribute to resistance against certain cationic antimicrobial peptides resistance upon LPS modification. Taken together, this work suggests that CrrAB regulates the palmitoylation of PGs and lipid A within the OM through upregulated PagP, which functions together to form an outer membrane barrier critical for bacterial survival.
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Background
A new mechanism for intercellular communication has recently emerged that involves intercellular transfer of extracellular vesicles (EVs). Several studies have indicated that EVs may play ...a potential role in cell‐to‐cell communication between macrophage foam cells and vascular smooth muscle cells (VSMCs) in atherosclerotic lesion.
Methods and Results
This study involved the comparison of circulating EVs from atherosclerotic patients and control participants. The results showed that the circulation of the patients contained more leukocyte‐derived EVs and that these EVs promoted more VSMC adhesion and migration than those of healthy participants. We then established a macrophage foam cell model and characterized the EVs from the macrophages. We used flow cytometric analyses and cell migration and adhesion assays and determined that the foam cells generated more EVs than the normal macrophages and that the foam cell–derived EVs were capable of promoting increased levels of VSMC migration and adhesion. Furthermore, we performed a proteomic analysis of the EVs. The data showed that the foam cell–derived EVs may promote VSMC adhesion and migration by regulating the actin cytoskeleton and focal adhesion pathways. In addition, Western blotting revealed that foam cell–derived EVs could promote the phosphorylation of ERK and Akt in VSMCs in a time‐dependent manner. We also found that foam cell–derived EVs could enter the VSMCs and transfer integrins to the surface of these cells.
Conclusions
The data in our present study provide the first evidence that EVs from foam cells could promote VSMC migration and adhesion, which may be mediated by the integration of EVs into VSMCs and the subsequent downstream activation of ERK and Akt.
Small extracellular vesicles (sEVs) are important mediators of intercellular communication by transferring of functional components (proteins, RNAs, and lipids) to recipient cells. Some PTMs, ...including phosphorylation and N-glycosylation, have been reported to play important role in EV biology, such as biogenesis, protein sorting and uptake of sEVs. MS-based proteomic technology has been applied to identify proteins and PTM modifications in sEVs. Previous proteomic studies of sEVs from C2C12 myoblasts, an important skeletal muscle cell line, focused on identification of proteins, but no PTM information on sEVs proteins is available.In this study, we systematically analyzed the proteome, phosphoproteome, and N-glycoproteome of sEVs from C2C12 myoblasts with LC-MS/MS. In-depth analyses of the three proteomic datasets revealed that the three proteomes identified different catalogues of proteins, and PTMomic analysis could expand the identification of cargos in sEVs. At the proteomic level, a high percentage of membrane proteins, especially tetraspanins, was identified. The sEVs-derived phosphoproteome had a remarkably high level of tyrosine-phosphorylated sites. The tyrosine-phosphorylated proteins might be involved with EPH-Ephrin signaling pathway. At the level of N-glycoproteomics, several glycoforms, such as complex N-linked glycans and sialic acids on glycans, were enriched in sEVs. Retrieving of the ligand-receptor interaction in sEVs revealed that extracellular matrix (ECM) and cell adhesion molecule (CAM) represented the most abundant ligand-receptor pairs in sEVs. Mapping the PTM information on the ligands and receptors revealed that N-glycosylation mainly occurred on ECM and CAM proteins, while phosphorylation occurred on different categories of receptors and ligands. A comprehensive PTM map of ECM-receptor interaction and their components is also provided.In summary, we conducted a comprehensive proteomic and PTMomic analysis of sEVs of C2C12 myoblasts. Integrated proteomic, phosphoproteomic, and N-glycoproteomic analysis of sEVs might provide some insights about their specific uptake mechanism.
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•Three generations of pyrite and quartz are identified in the Meiling deposit.•Lithium and Al compositions may control the CL intensity of Meiling quartz.•Pyrite Co/Ni ratio indicates ...a hydrothermal origin.•Abundant porous pyrite and trace element ratios indicates that boiling plays an important role in the metal precipitation.•Multistage sulfides and quartz compositions can effectively reconstruct hydrothermal fluid evolution process in the Meiling deposit.
The Meiling is a newly discovered Late Paleozoic epithermal Cu–Zn–Au deposit in the Kalatag arc, East Tianshan, NW China. Some key issues such as metal substitution mechanisms, physicochemical characteristics of ore-forming fluids and sulfide precipitation process are still unclear. In this contribution, we carried out a detailed trace element geochemistry of sulfides and quartz and in-situ sulfur isotopic compositions to characterize the ore-forming elements enrichment process. The ore-forming process can be divided into four stages, including quartz–pyrite, quartz–chalcopyrite–pyrite, quartz–chalcopyrite–sphalerite–pyrite and quartz–calcite–pyrite stage, respectively. Three generations of pyrite are identified in the Meiling deposit, including subhedral to anhedral pyrite (Py1), fine-grained pyrite (Py2) and irregular pyrite (Py3). Three generations of hydrothermal quartz (Qtz1, Qtz2, and Qtz3) are identified. Titanium, Al and Li compositions of Qtz1 are mostly higher than those of Qtz2 and Qtz3, indicating a higher formation pressure and temperature. Average Li compositions show a decreasing trend from Qtz1 to Qtz3, namely 42.8 ppm, 11.3 ppm, 5.3 ppm, respectively. Similar trends also appear in the Al compositions, indicating that the Li and Al compositions may control the CL intensity of quartz. The increasing pH from Qtz1 to Qtz3, combined with the alteration characteristic and the sequence of sulfide precipitation, indicating a clear relationship between pH and mineralization process in the Meiling deposit. LA–ICP–MS data shows that Py1 displays the highest compositions of Te (avg. 44.66 ppm) and Pb (avg. 361.95 ppm). Py2 contains the highest compositions of Cu (avg. 5643.85 ppm), Zn (avg. 436.72 ppm), As (avg. 15300.55 ppm), and Ag (avg. 146.70 ppm), whereas the Py3 contains the most Se (avg. 405.40 ppm), Au (avg. 18.65 ppm), Ni (avg. 19.45 ppm) and Co (avg. 12.64 ppm) compositions. In Py2, the high compositions of Cu and Pb may be due to the existence of inclusions in chalcopyrite and galena. Chalcopyrite is enriched in Ag, Te, Sb, Zn, Cd, In and Se and poor in Ge, Au and Bi. Sphalerite is characterized by high compositions of Ag, Cd, Fe, Mo, Cu, Ga and Sb. Cobalt/Ni ratios of Py1(avg. 1.7), Py2 (avg. 4.9), and Py3 (avg. 1.8), indicating a hydrothermal origin. Sulfur isotopic compositions of sulfides suggest that quartz porphyry is an important material source at Meiling deposit. Tellurium composition in Py1 (avg. 44.7 ppm) was significantly higher than that in Py2 (avg. 1.10 ppm) and Py3 (avg. 0.90 ppm), indicating that the fluid fO2 in stage II and III was higher than that in stage I. Moreover, stage II and III have nearly the same fO2 values. Arsenic enters pyrite in the form of As– instead of S– in the Meiling deposit, causing its lattice defects to promote Au+ to enter into pyrite. Au-As-rich Py3 and visible gold are most likely to be formed by direct precipitation from the new Au-As rich ore-forming fluid. Abundant porous pyrite and trace element ratios (e.g., Ag/As, Ag/Co) indicates that boiling plays an important role in the precipitation process of Py2 and Py3. In summary, trace element compositions of multistage sulfide and quartz can effectively reconstruct hydrothermal fluid evolution and metal enrichment process of Meiling epithermal Cu–Zn–Au mineralization system.
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•The Xiaotuergen granitoids were recognized as highly evolved I-type.•Continental arc dominated the entire Xinjiang Altay during the early Devonian.•Long-lived magmatism and mature ...arc environment provided favorable conditions.
The Xiaotuergen deposit is the first porphyry Cu deposit to be identified in the northern Xinjiang Altay, Northwest China. Voluminous granitoids comprising granite porphyry, granodiorite porphyry, biotite monzogranite, and quartz porphyry are present in the ore district. Granodiorite porphyry hosts the main Cu mineralization, in disseminated, veinlet, veinlet-disseminated, and stockwork forms. The Xiaotuergen intrusions are weakly metaluminous to peraluminous calc-alkaline to alkaline granitic rocks, and exhibit typical subduction-related geochemical signatures comprising light rare earth element (LREE) enrichment, high field strength element (HFSE) depletion, and low Sr/Y and La/Yb ratios. They are depleted in Nb–Ta–Ti, P, and Eu–Sr, yield moderate Mg# values (41.10–55.38), and show negative but near-zero εNd(t) values (−2.0 to −0.1) and variable positive εHf(t) values (+1.52 to +11.08). Geochemical constraints indicate that the Xiaotuergen granitoids are highly evolved I-type granites which were derived from strong fractional crystallization of a parental magma, mixed with materials derived from partial melting of both subducting oceanic sediments and the overlying mantle wedge. The Xiaotuergen granitoids are products of the same tectono-magmatic activity as that which produced the synchronous magmatic rocks of the Xinjiang Altay, having been formed in a continental arc setting during the early Devonian. The Xiaotuergen ore-bearing porphyries are identified as the shoshonite series, rather than the adakite series. Mantle-derived contributions played a crucial role in the formation of magmas with Cu and S contents that were high enough to produce economic mineralization. The mature arc environment and long-lived magmatism provided favorable conditions for the development of porphyry Cu mineralization.
Histone chaperone ASF1A has been reported to be dysregulated in multiple tumors; however, the underlying molecular mechanism that how the abundance and function of ASF1A are regulated remains ...unclear. Here we report that ASF1A is physically associated with USP52, which is previously identified as a pseudo-deubiquitinase. Interestingly, we demonstrate that USP52 is a bona fide ubiquitin-specific protease, and USP52 promotes ASF1A deubiquitination and stabilization. USP52-promoted ASF1A stabilization facilitates chromatin assembly and favors cell cycle progression. Additionally, we find that USP52 is overexpressed in breast carcinomas, and its level of expression correlates with that of ASF1A. Moreover, we reveal that impairment of USP52-promoted ASF1A stabilization results in growth arrest of breast cancer cells and sensitizes these cells to DNA damage. Our experiments identify USP52 as a truly protein deubiquitinase, uncover a molecular mechanism of USP52 in chromatin assembly, and reveal a potential role of USP52 in breast carcinogenesis.
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