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ABSTRACT A deep understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–host interactions is crucial to developing effective therapeutics and addressing the threat of emerging coronaviruses. The role of noncoding regions of viral RNA (ncrRNAs) has yet to be systematically scrutinized. We developed a method using MS2 affinity purification coupled with liquid chromatography-mass spectrometry and designed a diverse set of bait ncrRNAs to systematically map the interactome of SARS-CoV-2 ncrRNA in Calu-3, Huh7, and HEK293T cells. Integration of the results defined the core ncrRNA–host protein interactomes among cell lines. The 5′ UTR interactome is enriched with proteins in the small nuclear ribonucleoproteins family and is a target for the regulation of viral replication and transcription. The 3′ UTR interactome is enriched with proteins involved in the stress granules and heterogeneous nuclear ribonucleoproteins family. Intriguingly, compared with the positive-sense ncrRNAs, the negative-sense ncrRNAs, especially the negative-sense of 3′ UTR, interacted with a large array of host proteins across all cell lines. These proteins are involved in the regulation of the viral production process, host cell apoptosis, and immune response. Taken together, our study depicts the comprehensive landscape of the SARS-CoV-2 ncrRNA–host protein interactome and unveils the potential regulatory role of the negative-sense ncrRNAs, providing a new perspective on virus–host interactions and the design of future therapeutics. Given the highly conserved nature of UTRs in positive-strand viruses, the regulatory role of negative-sense ncrRNAs should not be exclusive to SARS-CoV-2. IMPORTANCE Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a pandemic affecting millions of lives. During replication and transcription, noncoding regions of the viral RNA (ncrRNAs) may play an important role in the virus–host interactions. Understanding which and how these ncrRNAs interact with host proteins is crucial for understanding the mechanism of SARS-CoV-2 pathogenesis. We developed the MS2 affinity purification coupled with liquid chromatography-mass spectrometry method and designed a diverse set of ncrRNAs to identify the SARS-CoV-2 ncrRNA interactome comprehensively in different cell lines and found that the 5′ UTR binds to proteins involved in U1 small nuclear ribonucleoprotein, while the 3′ UTR interacts with proteins involved in stress granules and the heterogeneous nuclear ribonucleoprotein family. Interestingly, negative-sense ncrRNAs showed interactions with a large number of diverse host proteins, indicating a crucial role in infection. The results demonstrate that ncrRNAs could serve diverse regulatory functions.

Density functional theory calculations are used to study the effect of several metal dopants (M = Ag, Cd, Co, Cu, Fe, Ni, Pt, Sc, Ti, and Zn) and metal–boron co‐dopants on the structure and catalytic property of g‐C3N4 2D monolayer. Using transition metals and boron (TM–B) as co‐dopants not only keeps the 2D structure stability of g‐C3N4 monolayer, but also alters the catalytic performance of the structures. The co‐doping of B in TM (TM = Pt, Zn, Cd, Ti, and Sc)‐doped g‐C3N4 leads to a significant increase in the hydrogen adsorption energy because hydrogen binding site changes from N to C. For TM–B (TM = Fe, Co, and Ni) co‐doped g‐C3N4, the hydrogen adsorption energy has no obvious change since the hydrogen binding site remains on C atom near the doped TM. However, the co‐doping of B in TM‐ (TM = Cu and Ag) doped g‐C3N4 leads to a significant reduction of hydrogen adsorption energy, making them good candidates for hydrogen evolution reaction. This study provides theoretical guidance for the experimental synthesis of TM–B co‐doped g‐C3N4 and paves a way for the design of a widely applicable non‐noble catalyst.

Primary hepatic carcinoma is a common malignant tumor. The classic molecular targeted drug sorafenib is costly and is only effective for some patients. Therefore, it is of great clinical significance to search for new molecular targeted drugs. Eupalinolide B (EB) from Eupatorium lindleyanum DC. is used to treat chronic tracheitis in clinical practice. However, the role of EB in hepatic carcinoma is unknown. In this study, we first measure the effect of EB on tumor growth in a xenograft model and PDX model. The cell proliferation and migration are also detected in human hepatocarcinoma cell lines (SMMC-7721 and HCCLM3). Then, we investigate cell cycle, cell apoptosis, cell necrosis, cell autophagy, and ferroptosis by flow cytometry, western blot analysis and electron microscopy. The results demonstrate that EB exerts anti-proliferative activity in hepatic carcinoma by blocking cell cycle arrest at S phase and inducing ferroptosis mediated by endoplasmic reticulum (ER) stress, as well as HO-1 activation. When HO-1 is inhibited, EB-induced cell death and ER protein expression are rescued. The migration-related mechanism consists of activation of the ROS-ER-JNK signaling pathway and is not connected to ferroptosis. In summary, we first discover that EB inhibits cell proliferation and migration in hepatic carcinoma, and thus EB is a promising anti-tumor compound that can be used for hepatic carcinoma.

Abstract Background CCCH zinc finger family is one of the largest transcription factor families related to multiple biotic and abiotic stresses. Brassica napus L., an allotetraploid oilseed crop formed by natural hybridization between two diploid progenitors, Brassica rapa and Brassica oleracea. A systematic identification of rapeseed CCCH family genes is missing and their functional characterization is still in infancy. Results In this study, 155 CCCH genes, 81 from its parent B. rapa and 74 from B. oleracea, were identified and divided into 15 subfamilies in B. napus. Organization and syntenic analysis explained the distribution and collinearity relationship of CCCH genes, the selection pressure and evolution of duplication gene pairs in B. napus genome. 44 diploid duplication gene pairs and 4 triple duplication gene groups were found in B. napus of CCCH family and the segmental duplication is attributed to most CCCH gene duplication events in B. napus. Nine types of CCCH motifs exist in B. napus CCCH family members, and motif C-X7/8-C-X5-C-X3-H is the most common and a new conserved CCH motif (C-X5-C-X3-H) has been identified. In addition, abundant stress-related cis-elements exist in promoters of 27 subfamily IX (RR-TZF) genes and their expression profiles indicated that RR-TZF genes could be involved in responses to hormone and abiotic stress. Conclusions The results provided a foundation to understand the basic characterization and genes evolution of CCCH gene family in B. napus, and provided potential targets for genetic engineering in Brassicaceae crops in pursuit of stress-tolerant traits.

Plants dynamically manipulate their gene expression in acclimation to the challenging environment. Hereinto, the histone methylation tunes the gene transcription via modulation of the chromatin accessibility to transcription machinery. Osmotic stress, which is caused by water deprivation or high concentration of ions, can trigger remarkable changes in histone methylation landscape and genome-wide reprogramming of transcription. However, the dynamic regulation of genes, especially how stress-inducible genes are timely epi-regulated by histone methylation remains largely unclear. In this review, recent findings on the interaction between histone (de)methylation and osmotic stress were summarized, with emphasis on the effects on histone methylation profiles imposed by stress and how histone methylation works to optimize the performance of plants under stress.

Ascorbate peroxidase (APX) plays an important role in scavenging H2O2 and balancing ROS content in plant cells, which is of great significance for the growth and development of life and resistance to external stress. However, up to now, APXs in Brassica napus (B. napus) have not been systematically characterized. In this study, a total of 26 BnaAPX genes were identified, which were distributed on 13 chromosomes and divided into five phylogenetic branches. Gene structure analysis showed that they had a wide varied number of exons while BnaAPXs proteins contained more similar motifs in the same phylogenetic branches. qRT-PCR analysis of 26 BnaAPX gene expression patterns showed that three putative cytosol BnaAPX genes BnaAPX1, BnaAPX2, BnaAPX9, two putatice microsomal genes BnaAPX18 and BnaAPX25 were up-regulated rapidly and robustly under high salt, water shortage and high temperature stresses. In addition, the above three abiotic stresses led to a significant increase in APX activity. The results provide basic and comprehensive information for further functional characterization of APX gene family in B. napus.

Abstract Methodological choices can have strong effects on projections of climate change impacts on hydrology. In this study, we investigate the ways in which four different steps in the modeling chain influence the spread in projected changes of different aspects of hydrology. To form the basis of these analyses, we constructed an ensemble of 160 simulations from permutations of two Representative Concentration Pathways, 10 global climate models, two downscaling methods, and four hydrologic model implementations. The study is situated in the Pacific Northwest of North America, which has relevance to a diverse, multinational cast of stakeholders. We analyze the effects of each modeling decision on changes in gridded hydrologic variables of snow water equivalent and runoff, as well as streamflow at point locations. Results show that the choice of representative concentration pathway or global climate model is the driving contributor to the spread in annual streamflow volume and timing. On the other hand, hydrologic model implementation explains most of the spread in changes in low flows. Finally, by grouping the results by climate region the results have the potential to be generalized beyond the Pacific Northwest. Future hydrologic impact assessments can use these results to better tailor their modeling efforts.

Abstract Millions of people died due to famines in India in the nineteenth and twentieth centuries; however, the relationship of historical famines with drought is complicated and not well understood. Using station‐based observations and simulations, we reconstruct soil moisture (agricultural) drought in India for the period 1870–2016. We show that over this century and a half period, India experienced seven major drought periods (1876–1882, 1895–1900, 1908–1924, 1937–1945, 1982–1990, 1997–2004, and 2011–2015) based on severity‐area‐duration analysis of reconstructed soil moisture. Out of six major famines (1873–74, 1876, 1877, 1896–97, 1899, and 1943) that occurred during 1870–2016, five are linked to soil moisture drought, and one (1943) was not. The three most deadly droughts (1877, 1896, and 1899) were linked with the positive phase of El Niño–Southern Oscillation. Five major droughts were not linked with famine, and three of those five nonfamine droughts occurred after Indian independence in 1947.

Abstract Crosslinking immunoprecipitation sequencing (CLIP-seq) technologies have enabled researchers to characterize transcriptome-wide binding sites of RNA-binding protein (RBP) with high resolution. We apply a soft-clustering method, RBPgroup, to various CLIP-seq datasets to group together RBPs that specifically bind the same RNA sites. Such combinatorial clustering of RBPs helps interpret CLIP-seq data and suggests functional RNA regulatory elements. Furthermore, we validate two RBP–RBP interactions in cell lines. Our approach links proteins and RNA motifs known to possess similar biochemical and cellular properties and can, when used in conjunction with additional experimental data, identify high-confidence RBP groups and their associated RNA regulatory elements.

Photocatalytic water splitting, which directly converts solar energy into hydrogen, is one of the most desirable solar-energy-conversion approaches. The ultimate target of photocatalysis is to explore efficient and stable photocatalysts for solar water splitting. Tantalum (oxy)nitride-based materials are a class of the most promising photocatalysts for solar water splitting because of their narrow bandgaps and sufficient band energy potentials for water splitting. Tantalum (oxy)nitride-based photocatalysts have experienced intensive exploration, and encouraging progress has been achieved over the past years. However, the solar-to-hydrogen (STH) conversion efficiency is still very far from its theoretical value. The question of how to better design these materials in order to further improve their water-splitting capability is of interest and importance. This review summarizes the development of tantalum (oxy)nitride-based photocatalysts for solar water spitting. Special interest is paid to important strategies for improving photocatalytic water-splitting efficiency. This paper also proposes future trends to explore in the research area of tantalum-based narrow bandgap photocatalysts for solar water splitting.

Artemisia annua is an important medicinal plant producing the majority of the antimalarial compound artemisinin. Jasmonates are potent inducers of artemisinin accumulation in Artemisisa annua plants. As the receptor of jasmonates, the F-box protein COI1 is critical to the JA signaling required for plant development, defense, and metabolic homeostasis. AaCOI1 from Artemisia annua, homologous to Arabidopsis AtCOI1, encodes a F-box protein located in the nuclei. Expressional profiles of the AaCOI1 in the root, stem, leaves, and inflorescence was investigated. The mRNA abundance of AaCOI1 was the highest in inflorescence, followed by in the leaves. Upon mechanical wounding or MeJA treatment, expression of AaCOI1 was upregulated after 6 h. When ectopically expressed, driven by the native promoter from Arabidopsis thaliana, AaCOI1 could partially complement the JA sensitivity and defense responses, but fully complemented the fertility, and the JA-induced anthocyanin accumulation in a coi1-16 loss-of-function mutant. Our study identifies the paralog of AtCOI1 in Artemisia annua, and revealed its implications in development, hormone signaling, defense, and metabolism. The results provide insight into JA perception in Artemisia annua, and pave the way for novel molecular breeding strategies in the canonical herbs to manipulate the anabolism of pharmaceutic compounds on the phytohormonal level.

Washington State experienced widespread drought in 2015 and the largest burned area in the observational record, attributable in part to exceptionally low winter snow accumulation and high summer temperatures. We examine 2015 drought severity in the Cascade and Olympic mountains relative to the historical climatology (1950–present) and future climate projections (mid-21st century) for a mid-range global greenhouse gas emissions scenario. Although winter precipitation was near normal, the regional winter temperature anomaly was +2.1 °C (+2.0σ) in 2015, consistent with projections of a +2.3 °C (+2.2σ) temperature change and near normal precipitation in the future, relative to the climatology. April 1 snow water equivalent in 2015, −325 mm (−1.5σ), and the future, −252 mm (−1.1σ), were substantially lower than the climatology. Wildfire potential, as indicated by dead fuel moisture content, was higher in 2015 than mid-21st century mean projections. In contrast to most historical droughts, which have been driven by precipitation deficits, our results suggest that 2015 is a useful analog of typical conditions in the Pacific Northwest by the mid-21st century.