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In this paper, we will conclude the results of Bufeng-1 (BF-1) A/B data processing, calibration workflow, and validation of the calibrated sea surface winds, land surface soil moisture, and sea surface height measurements. Since 2019, the BF-1 mission has operated in-orbit for over 4 years. The Earth reflected delay Doppler maps (DDMs) are continuously collected to perform global sea surface and land observations. At the same time, the intermediate frequency (IF) raw data are also obtained for 12 seconds every pass in diagnostic mode. To begin with, a brief description of the spaceborne Global Navigation Satellite System Reflectometry (GNSS-R) technique will be provided in the introduction. Next, we will present the overview of Chinese BF-1 mission and the data specifications used in our research. In the next section, the BF-1 mission-related spaceborne power calibration and validation are presented to show the support to power DDM observable production for sea surface and land surface applications. Then, the status of Chinese Beidou System (BDS) Equivalent Isotropic Radiated Power (EIRP) acquisition programme is then introduced. Furthermore, the latest sea surface height (SSH) measurements results including two modes (group delay and carrier phase) and wind speed derivation based on machine learning (ML) method will be spatial-temporal aligned and validated with auxiliary datasets including Denmark Technology University (DTU) mean sea surface (MSS) products and European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 reanalysis. The previous published results of sea surface winds retrieval under Hurricane conditions and soil moisture retrieval are also reviewed for the BF-1 mission applications. Finally, the conclusion of BF-1 derived results will be discussed to draw out ongoing/future works. [ABSTRACT FROM AUTHOR]

Oxidation of sulfide to sulfone is a fundamental process to produce many important pharmaceutical compounds. Formerly, efficient methods have been reported for the synthesis of sulfones from sulfides. Yet some limitations were identified, such as the unbalance use of metal catalysts and expensive oxidizing agent, low reaction yields and production of by-products. In this current research, oxidation of sulfides to sulfones is described in the presence of samarium oxide (Sm2O3) along with hydrogen peroxide. The SEM image showed the crystalline morphology of the Sm2O3 as a cubic single phase (ICSD 98-001-2948) with a size distribution between 120 and 300 nm. In the recyclability experiment, Sm2O3 catalyst can be reutilized for five successive cycles and afforded the desired end-products in great yields (97–95%). This current work is vital, as the usage of non-endangered metals in organic transformation is geared towards achieving the elemental sustainability concept. [ABSTRACT FROM AUTHOR]

Autophagy has emerged as a key regulator of cell metabolism. Recently, we have demonstrated that autophagy is involved in RNA metabolism by regulating ribosomal RNA (rRNA) synthesis. We found that autophagy-deficient cells display much higher 47S precursor rRNA level, which is caused by the accumulation of SQSTM1/p62 (sequestosome 1) but not other autophagy receptors. Mechanistically, SQSTM1 accumulation potentiates the activation of MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) signaling, which facilitates the assembly of RNA polymerase I pre-initiation complex at ribosomal DNA (rDNA) promoter regions and leads to the activation of rDNA transcription. Finally, we showed that SQSTM1 accumulation is responsible for the increase in protein synthesis, cell growth and cell proliferation in autophagy-deficient cells. Taken together, our findings reveal a regulatory role of autophagy and autophagy receptor SQSTM1 in rRNA synthesis and may provide novel mechanisms for the hyperactivated rDNA transcription in autophagy-related human diseases. Abbreviations: 5-FUrd: 5-fluorouridine; LAP: MAP1LC3/LC3-associated phagocytosis; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; PIC: pre-initiation complex; POLR1: RNA polymerase I; POLR1A: RNA polymerase I subunit A; rDNA: ribosomal DNA; RRN3: RRN3 homolog, RNA polymerase I transcription factor; rRNA: ribosomal RNA; SQSTM1/p62: sequestosome 1; TP53INP2: tumor protein p53 inducible nuclear protein 2; UBTF: upstream binding transcription factor. [ABSTRACT FROM AUTHOR]

Macroautophagy/autophagy, a highly conserved lysosome-dependent degradation pathway, has been intensively studied in regulating cell metabolism by degradation of intracellular components. In this study, we link autophagy to RNA metabolism by uncovering a regulatory role of autophagy in ribosomal RNA (rRNA) synthesis. Autophagy-deficient cells exhibit much higher 47S precursor rRNA level, which is caused by the accumulation of SQSTM1/p62 (sequestosome 1) but not other autophagy receptors. Mechanistically, SQSTM1 accumulation potentiates the activation of MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) signaling and promotes the assembly of RNA polymerase I pre-initiation complex at ribosomal DNA (rDNA) promoters, which leads to an increase of 47S rRNA transcribed from rDNA. Functionally, autophagy deficiency promotes protein synthesis, cell growth and cell proliferation, both of which are dependent on SQSTM1 accumulation. Taken together, our findings suggest that autophagy deficiency is involved in RNA metabolism by activating rDNA transcription and provide novel mechanisms for the reprogramming of cell metabolism in autophagy-related diseases including multiple types of cancers. Abbreviations: 5-FUrd: 5-fluorouridine; AMPK: AMP-activated protein kinase; ATG: autophagy related; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; ChIP: chromatin immunoprecipitation; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAPK/ERK: mitogen-activated protein kinase; MTOR: mechanistic target of rapamycin kinase; NBR1: NBR1 autophagy cargo receptor; NFKB/NF-κB: nuclear factor kappa B; NFE2L2/NRF2: nuclear factor, erythroid 2 like 2; OPTN: optineurin; PIC: pre-initiation complex; POLR1: RNA polymerase I; POLR1A/RPA194: RNA polymerase I subunit A; POLR2A: RNA polymerase II subunit A; rDNA: ribosomal DNA; RPS6KB1/S6K1: ribosomal protein S6 kinase B1; rRNA: ribosomal RNA; RUBCN/Rubicon: rubicon autophagy regulator; SQSTM1/p62: sequestosome 1; STX17: syntaxin 17; SUnSET: surface sensing of translation; TAX1BP1: Tax1 binding protein 1; UBTF/UBF1: upstream binding transcription factor; WIPI2: WD repeat domain, phosphoinositide interacting 2; WT: wild-type. [ABSTRACT FROM AUTHOR]

The fusion of autophagosomes and endosomes/lysosomes, also called autophagosome maturation, ensures the degradation of autophagic cargoes. It is an important regulatory step of the macroautophagy/autophagy process. STX17 is the key autophagosomal SNARE protein that mediates autophagosome maturation. Here, we report that the acetylation of STX17 regulates its SNARE activity and autophagic degradation. The histone acetyltransferase CREBBP/CBP and the deacetylase HDAC2 specifically regulate the acetylation of STX17. In response to cell starvation and MTORC1 inhibition, the inactivation of CREBBP leads to the deacetylation of STX17 at its SNARE domain. This deacetylation promotes the interaction between STX17 and SNAP29 and the formation of the STX17-SNAP29-VAMP8 SNARE complex with no effect on the recruitment of STX17 to autophagosomal membranes. Deacetylation of STX17 also enhances the interaction between STX17 and the tethering complex HOPS, thereby further promoting autophagosome-lysosome fusion. Our study suggests a mechanism by which acetylation regulates the late-stage of autophagy, and possibly other STX17-related intracellular membrane fusion events. Abbreviations: ACTB: actin beta; CREBBP/CBP: CREB binding protein; Ctrl: control; GFP: green fluorescent protein; GST: glutathione S-transferase; HDAC: histone deacetylase; HOPS: homotypic fusion and protein sorting complex; KO: knockout; LAMP1/2: lysosomal associated membrane protein 1/2; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MEFs: mouse embryonic fibroblasts; MS: mass spectrometry; MTORC1: mechanistic target of rapamycin kinase complex 1; NAM: nicotinamide; PtdIns3K: phosphatidylinositol 3-kinase; RFP: red fluorescent protein; SNAP29: synaptosome associated protein 29; SNARE: soluble N-ethylamide-sensitive factor attachment protein receptor; SQSTM1/p62: sequestosome 1; STX17: syntaxin 17; TSA: trichostatin A; TSC1/2: TSC complex subunit 1/2; VAMP8: vesicle associated membrane protein 8; WT: wild type. [ABSTRACT FROM AUTHOR]

Ribosomal DNA (rDNA) transcription drives cell growth and cell proliferation via the product ribosomal RNA (rRNA), the essential component of ribosome. Given the fundamental role of rRNA in ribosome biogenesis, rDNA transcription has emerged as one of the effective targets for a number of human diseases including various types of cancers. In this study, we identify curcumin, an ancient drug, as a novel natural inhibitor of rDNA transcription. Curcumin treatment impairs the assembly of the RNA polymerase I preinitiation complex at rDNA promoters and represses rDNA promoter activity, which leads to the decrease of rRNA synthesis. In addition, curcumin treatment stimulates autophagosome formation and promotes autophagic degradation in cells. Mechanistically, curcumin inactivates the mechanistic target of rapamycin complex 1 (mTORC1), the upstream regulator of rDNA transcription and autophagy induction, by inhibiting mTOR lysosomal localization. Functionally, curcumin treatment inhibits protein synthesis, cell growth and cell proliferation. Taken together, these findings identify curcumin as an effective inhibitor of rDNA transcription and provide novel mechanisms for the anticancer properties of curcumin. Abbreviations: Atg: autophagy-related; GFP: green fluorescent protein; LAMP2: lysosomal associated membrane protein 2; LC3: microtubule-associated protein 1 light chain 3; MEF: mouse embryonic fibroblast; mTORC1: mechanistic target of rapamycin complex 1; rDNA: ribosomal DNA; rRNA: ribosomal RNA; TP53INP2: tumor protein p53 inducible nuclear protein 2. [ABSTRACT FROM AUTHOR]

Phospholipase D1 (PLD1) is an enzyme of the phospholipase D (PLD) superfamily. It is involved in the occurrence of various tumors. However, its role in multiple myeloma (MM) remained undefined. This study aimed to investigate the mechanism of PLD1 in the therapy of myeloma disease. Cell lines U266 and H929 were treated with PLD1 specific inhibitor VU0359595 combined bortezomib, a proteasome inhibitor. Their effects on MM cell proliferation, apoptosis, and relevant signal pathways of apoptosis were determined by cell counting kit-8 (CCK-8), real-time polymerase reaction chain (RT–PCR), ATP assay, and western blot. PLD1 was highly expressed in U266 and H929 cells. VU0359595 didn't affect the proliferation and apoptosis of MM cells. However, VU0359595 could enhance growth inhibition, decreasing mitochondrial membrane potentials (MMPs) and ATP levels of bortezomib treated MM cells. VU0359595 also strengthened bortezomib-induced apoptosis via activating caspase-8, caspase-9, caspase-3; and down-regulating the expressions of anti-apoptosis proteins BCL-2. In addition, the bortezomib-induced cytotoxicity on MM cells was significantly augmented by VU0359595 through efficient suppression of the mTOR/NF-κB signal pathway. PLD1 inhibition can remarkably exert antitumor effects with bortezomib on MM, which is a novel potentially targeting therapeutic agent, especially for drug-resistant MM patients. [ABSTRACT FROM AUTHOR]

TP53INP2/DOR (tumor protein p53-inducible nuclear protein 2) contributes to mammalian macroautophagy/autophagy by carrying nuclear deacetylated MAP1LC3/LC3 to the cytoplasm. Here, we report that in the cytoplasm, TP53INP2 further functions in autophagosome biogenesis by promoting LC3B-ATG7 interaction. Cytoplasmic expression of the N-terminal region of TP53INP2, which includes the LC3-interacting region, effectively triggered LC3B–PE production and autophagosome formation. In the cytoplasm, TP53INP2 colocalized to early autophagic membrane structures containing ATG14, ZFYVE1/DFCP1 or WIPI2. While knockdown of TP53INP2 did not affect the formation of these autophagic structures, deletion of BECN1 or Atg5, or mutations preventing TP53INP2 from LC3 interaction, disrupted the membrane binding of TP53INP2. TP53INP2 interacted directly with ATG7 to form a LC3B-TP53INP2-ATG7 complex in the cytoplasm. Loss of TP53INP2-LC3 or TP53INP2-ATG7 interaction significantly reduced LC3B-ATG7 binding. Together, these results suggest that after shifting from the nucleus, cytoplasmic TP53INP2 is targeted to early autophagic membranes accompanied by LC3, where it contributes to autophagosome biogenesis by mediating LC3-ATG7 interaction. Abbreviations: 3-MA, 3-methyladenine; 3NES, 3 repeated nuclear export signal; 3NLS, 3 repeated nuclear localization signal; ACTB, actin beta; ATG, autophagy related; BECN1, Beclin 1; mCherry, monomeric red fluorescent protein mCherry; GFP, green fluorescent protein; GST, glutathione S-transferase; KO, knockout; LC3B/MAP1LC3B, microtubule-associated protein 1 light chain 3 beta; LC3B[G120], LC3B mutant lacking amino acids after glycine 120; LDH, lactate dehydrogenase; LMNB1, lamin B1; LIR, LC3-interacting region; MTORC1, mechanistic target of rapamycin complex 1; PE, phosphatidylethanolamine; PtdIns3K, phosphatidylinositol 3-kinase; PtdIns3P, phosphatidylinositol 3-phosphate; rDNA, ribosomal DNA; RFP, red fluorescent protein; RNAi, RNA interference; SQSTM1, sequestosome 1; TP53INP2, tumor protein p53-inducible nuclear protein 2; TP53INP2[1-28], TP53INP2 mutant containing amino acids 1 to 28; TP53INP2[28-45], TP53INP2 mutant containing amino acids 28 to 45; TP53INP2[LIRΔ], TP53INP2 mutant lacking amino acids 1 to 144; TP53INP2[NLSΔ], TP53INP2 mutant lacking amino acids 145 to 221; TP53INP2W35,I38A, TP53INP2 mutant in which tryptophan 35 and isoleucine 38 are replaced with alanine; TP53INP2W35,I38A[NLSΔ], TP53INP2 mutant lacking amino acids 145 to 221, and tryptophan 35 and isoleucine 38 are replaced with alanine; TP53INP2W35,I38A[Δ1-28],[NLSΔ], TP53INP2 mutant lacking amino acids 1 to 28 and amino acids 145 to 221, and tryptophan 35 and isoleucine 38 are replaced with alanine; TP53INP2[Δ1-28],[NLSΔ], TP53INP2 mutant lacking amino acids 1 to 28 and amino acids 145 to 221; TP53INP2[Δ67-111],[NLSΔ], TP53INP2 mutant lacking amino acids 67 to 111 and amino acids 145 to 221; TP53INP2[Δ112-144],[NLSΔ], TP53INP2 mutant lacking amino acids 112 to 144 and amino acids 145 to 221; TUBB, tubulin beta class I; ULK1, unc-51 like autophagy activating kinase 1; VMP1, vacuole membrane protein 1; WIPI2, WD repeat domain phosphoinositide-interacting 2; WT, wild-type; ZFYVE1/DFCP1, zinc finger FYVE-type containing 1. [ABSTRACT FROM AUTHOR]

This study uses a simultaneous equation model based on a three-stage least squares estimation to offer new empirical evidence that investors are hedgers or speculators during South Korea's elections. Major investor groups include individuals, securities companies, and foreigners in the Korea Composite Stock Price Index (KOSPI 200) market. The results show that cash market volatility and futures market activity have lead behaviors with one another. However, the contemporaneous variables of cash market volatility and options market activity have only unidirectional causality. Most investors will trade futures and options contracts for speculating within the entire sample period. During political election periods, investors prefer to trade options contracts for hedging rather than futures contracts. [ABSTRACT FROM AUTHOR]