Gibberellins regulate masculinization through the SpGAI-SpSTM module in dioecious spinach.

The sex of dioecious plants is mainly determined by genetic factors, but it can also be converted by environmental cues such as exogenous phytohormones. Gibberellic acids (GAs) are well-known inducers of flowering and sexual development, yet the pathway of gibberellin-induced sex conversion in dioecious spinach (Spinacia oleracea L.) remains elusive. Based on sex detection before and after GA3 application using T11A and SSR19 molecular markers, we confirmed and elevated the masculinization effect of GA on a single female plant through exogenous applications of GA3, showing complete conversion and functional stamens. Silencing of GIBBERELLIC ACID INSENSITIVE (SpGAI), a single DELLA family protein that is a central GA signaling repressor, results in similar masculinization. We also show that SpGAI can physically interact with the spinach KNOX transcription factor SHOOT MERISTEMLESS (SpSTM), which is a homolog of the flower meristem identity regulator STM in Arabidopsis. The silencing of SpSTM also masculinized female flowers in spinach. Furthermore, SpSTM could directly bind the intron of SpPI to repress SpPI expression in developing female flowers. Overall, our results suggest that GA induces a female masculinization process through the SpGAI-SpSTM-SpPI regulatory module in spinach. These insights may help to clarify the molecular mechanism underlying the sex conversion system in dioecious plants while also elucidating the physiological basis for the generation of unisexual flowers so as to establish dioecy in plants.

Lineage-specific amplification and epigenetic regulation of LTR-retrotransposons contribute to the structure, evolution, and function of Fabaceae species.

BACKGROUND: Long terminal repeat (LTR)-retrotransposons (LTR-RTs) are ubiquitous and make up the majority of nearly all sequenced plant genomes, whereas their pivotal roles in genome evolution, gene expression regulation as well as their epigenetic regulation are still not well understood, especially in a large number of closely related species. RESULTS: Here, we analyzed the abundance and dynamic evolution of LTR-RTs in 54 species from an economically and agronomically important family, Fabaceae, and also selected two representative species for further analysis in expression of associated genes, transcriptional activity and DNA methylation patterns of LTR-RTs. Annotation results revealed highly varied proportions of LTR-RTs in these genomes (5.1%~68.4%) and their correlation with genome size was highly positive, and they were significantly contributed to the variance in genome size through species-specific unique amplifications. Almost all of the intact LTR-RTs were inserted into the genomes 4 Mya (million years ago), and more than 50% of them were inserted in the last 0.5 million years, suggesting that recent amplifications of LTR-RTs were an important force driving genome evolution. In addition, expression levels of genes with intronic, promoter, and downstream LTR-RT insertions of Glycine max and Vigna radiata, two agronomically important crops in Fabaceae, showed that the LTR-RTs located in promoter or downstream regions suppressed associated gene expression. However, the LTR-RTs within introns promoted gene expression or had no contribution to gene expression. Additionally, shorter and younger LTR-RTs maintained higher mobility and transpositional potential. Compared with the transcriptionally silent LTR-RTs, the active elements showed significantly lower DNA methylation levels in all three contexts. The distributions of transcriptionally active and silent LTR-RT methylation varied across different lineages due to the position of LTR-RTs located or potentially epigenetic regulation. CONCLUSION: Lineage-specific amplification patterns were observed and higher methylation level may repress the activity of LTR-RTs, further influence evolution in Fabaceae species. This study offers valuable clues into the evolution, function, transcriptional activity and epigenetic regulation of LTR-RTs in Fabaceae genomes.

Impact of LTR-Retrotransposons on Genome Structure, Evolution, and Function in Curcurbitaceae Species.

Long terminal repeat (LTR)-retrotransposons (LTR-RTs) comprise a major portion of many plant genomes and may exert a profound impact on genome structure, function, and evolution. Although many studies have focused on these elements in an individual species, their dynamics on a family level remains elusive. Here, we investigated the abundance, evolutionary dynamics, and impact on associated genes of LTR-RTs in 16 species in an economically important plant family, Cucurbitaceae. Results showed that full-length LTR-RT numbers and LTR-RT content varied greatly among different species, and they were highly correlated with genome size. Most of the full-length LTR-RTs were amplified after the speciation event, reflecting the ongoing rapid evolution of these genomes. LTR-RTs highly contributed to genome size variation via species-specific distinct proliferations. The Angela and Tekay lineages with a greater evolutionary age were amplified in Trichosanthes anguina, whereas a recent activity burst of Reina and another ancient round of Tekay activity burst were examined in Sechium edule. In addition, Tekay and Retand lineages belonging to the Gypsy superfamily underwent a recent burst in Gynostemma pentaphyllum. Detailed investigation of genes with intronic and promoter LTR-RT insertion showed diverse functions, but the term of metabolism was enriched in most species. Further gene expression analysis in G.pentaphyllum revealed that the LTR-RTs within introns suppress the corresponding gene expression, whereas the LTR-RTs within promoters exert a complex influence on the downstream gene expression, with the main function of promoting gene expression. This study provides novel insights into the organization, evolution, and function of LTR-RTs in Cucurbitaceae genomes.

Protein Phosphatase 2A B'α and B'ß Protect Centromeric Cohesion during Meiosis I.

During meiosis, the stepwise release of sister chromatid cohesion is crucial for the equal distribution of genetic material to daughter cells, enabling generation of fertile gametophytes. However, the molecular mechanism that protects centromeric cohesion from release at meiosis I is unclear in Arabidopsis (Arabidopsis thaliana). Here, we report that the protein phosphatase 2A regulatory subunits B'α and B'ß participate in the control of sister chromatid separation. The double mutant b'αß exhibited severe male and female sterility, caused by the lack of a nucleus or presence of an abnormal nucleus in mature microspores and embryo sacs. 4',6-Diamidino-2-phenylindole staining revealed unequal amounts of DNA in the mononuclear microspores. Transverse sections of the anthers revealed unevenly sized tetrads with or without a nucleus, suggesting a defect in meiocyte meiosis. An analysis of chromosome spreads showed that the sister chromatids separated prematurely at anaphase I in b'αß Immunoblotting showed that AtRECOMBINATION DEFECTIVE8 (AtREC8), a key member of the cohesin complex, was hyperphosphorylated in b'αß anthers and pistils during meiosis but hypophosphorylated in the wild type. Furthermore, yeast two-hybrid and bimolecular fluorescence complementation assays showed that B'α and B'ß interact specifically with AtREC8, AtSHUGOSHIN1 (AtSGO1), AtSGO2, and PATRONUS1. Given that B'α was reported to localize to the centromere in meiotic cells, we propose that protein phosphatase 2A B'α and B'ß are recruited by AtSGO1/2 and PATRONUS1 to dephosphorylate AtREC8 at the site of centromere cohesion to shield it from cleavage until anaphase II, contributing to the balanced separation of sister chromatids at meiosis.

[Processing FBG Sensing Signals with Exponent Modified Gaussian Curve Fitting Peak Detection Method].

The system based on Fiber Bragg Grating (FBG) sensor is used in various fields, because of its advantages of high detection accuracy, good repeatability and adaptability. While the FBG sensor is a wavelength modulation type sensor, so the outside parameter detection is the center wavelength of FBG detection. At the same time, the FBG center wavelength corresponding to the peak value of the FBG reflection spectrum. Therefore, the core of demodulation system is the demodulation of FBG reflection spectrum during peak-seeking, and the high-precision peak detecting algorithm is the key technology of the system demodulation. The current peak detecting algorithms has a precondition for peak detection on FBG reflective spectrum, that the FBG reflective spectrum was a standard Gaussian model. But FBG reflective spectrum is not a standard Gaussian spectrum owing to the practical manufacture process and the individual environment; actually, it is an asymmetrical Gaussian spectrum. The experiment would achieve a lower accuracy because of this asymmetric property during peak-seeking. Based on the defect of the existing algorithm, an Exponent Modified Gaussian (EMG) Curve Fitting peak detecting algorithm is proposed in this paper. In the proposed algorithm, the coarse location was first determined by three times judgments and it can remove the false peak and peak invalid at the same time. Based on this, as the center of the coarse localization point to reconstruct the spectrum, and using the integral to judge the peak bias; then according to different peak bias, it revised the peak by the prepared exponential modified function. Simulation results show that at normal temperature or under variable temperature conditions, by comparing with direct peak searching algorithm, Gaussian fitting algorithm and the algorithm proposed by literature, the error of EMG peak detection algorithm is the minimum and high peak detecting precision. The algorithm proposed in this paper considers the FBG reflection spectrum characteristic of asymmetric effect. From its spectrum character, the EMG algorithm solves the problem of the limits of traditional peak detecting algorithm, meanwhile also guarantees a high-precision peak search results.

Examining the Effects of Biochar Application on Soil Phosphorus Levels and Phosphatase Activities with Visible and Fluorescence Spectroscopy

Biochar could be got from crop straw which contain rich carbon under oxygen free or oxygen limited conditions at low temperature. The application of biochar into soil is beneficial to ease the pressure of handling straw, reduce pollution, reduce greenhouse gas emissions and improve soil quality. This study was carried out in a cornfield containing meadow brown soil at the lower reaches of Liao River which was treated with different amounts of biochar (0, 360, 1 800, 3 600 kg·ha-1) and fertilizer. We investigated the contents of soil available phosphorus (AP), organic P (OP) and total P (TP). We also investigated the enzyme activities of soil acid phosphatase (AcP), alkaline phosphatase (AlP) and phosphodiesterase (PD) via a fluorescence spectroscopy method by using a fluorescent conjugated polymer as the substrate. Soil AP contents increased drastically with the increasing application of biochar, whereas the OP and TP contents exhibited little change. The increase in AP contents was ascribed to the introduction of P into the soil via biochar. Soil AlP and PD activities increased with increasing biochar application. Soil AcP activity increased significantly after the application of the appropriate amount of biochar (1 800 kg·ha-1), whereas it was inhibited by the application of high levels of biochar (3 600 kg·ha-1), perhaps due to the intrinsic alkalinity of biochar. The effect of Biochar inputs on soil phosphorus element and phosphatase activity is the comprehensive embodiment of the soil physical properties, chemical properties, and microbial community structure and metabolic capacity. We should further study such item. The fluorescent microplate method used in this study has many advantages, such as accuracy, rapidness and simple to perform.

Identification of BZR1-interacting proteins as potential components of the brassinosteroid signaling pathway in Arabidopsis through tandem affinity purification.

Brassinosteroids (BRs) are essential phytohormones for plant growth and development. BRs are perceived by the cell surface receptor kinase BRI1, and downstream signal transduction through multiple components leads to activation of the transcription factors BZR1 and BZR2/BES1. BZR1 activity is highly controlled by BR through reversible phosphorylation, protein degradation, and nucleocytoplasmic shuttling. To further understand the molecular function of BZR1, we performed tandem affinity purification of the BZR1 complex and identified BZR1-associated proteins using mass spectrometry. These BZR1-associated proteins included several known BR signaling components, such as BIN2, BSK1, 14-3-3λ, and PP2A, as well as a large number of proteins with previously unknown functions in BR signal transduction, including the kinases MKK5 and MAPK4, histone deacetylase 19, cysteine proteinase inhibitor 6, a DEAD-box RNA helicase, cysteine endopeptidases RD21A and RD21B, calmodulin-binding transcription activator 5, ubiquitin protease 12, cyclophilin 59, and phospholipid-binding protein synaptotagmin A. Their interactions with BZR1 were confirmed by in vivo and in vitro assays. Furthermore, MKK5 was found to phosphorylate BZR1 in vitro. This study demonstrates an effective method for purifying proteins associated with low-abundance transcription factors, and identifies new BZR1-interacting proteins with potentially important roles in BR response.

Effect of Exogenous Phytase Addition on Soil Phosphatase Activities: a Fluorescence Spectroscopy Study.

The utilization of organic phosphorus (P) has directly or indirectly improved after exogenous phytase was added to soil. However, the mechanism by which exogenous phytase affected the soil phosphatases (phosphomonoesterase and phosphodiesterase) activities was not clear. The present work was aimed to study red soil, brown soil and cinnamon soil phosphomonoesterase (acid and alkaline) (AcP and AlP) and phosphodiesterase (PD) activities responding to the addition of exogenous phytase (1 g phytase/50 g air dry soil sample) based on the measurements performed via a fluorescence detection method combined with 96 microplates using a TECAN Infinite 200 Multi-Mode Microplate Reader. The results indicated that the acid phosphomonoesterase activity was significantly enhanced in red soil (p≤0. 01), while it was significantly reduced in cinnamon soil; alkaline phosphomonoesterase activity was significantly enhanced in cinnamon soil (p≤ 0. 01), while it was significantly reduced in red soil; phosphodiesterase activity was increased in three soils but it was significantly increased in brown soil (p≤0. 01) after the addition of exogenous phytase. The activities still remained strong after eight days in different soils, which indicated that exogenous phytase addition could be enhance soil phosphatases activities effectively. This effect was not only related to soil properties, such as pH and phosphorus forms, but might also be related to the excreted enzyme amount of the stimulating microorganism. Using fluorescence spectroscopy to study exogenous phytase addition influence on soil phosphatase activities was the first time at home and abroad. Compared with the conventional spectrophotometric method, the fluorescence microplate method is an accurate, fast and simple to use method to determine the relationships among the soil phosphatases activities.

In vitro and in vivo antitumor activity of scutebarbatine A on human lung carcinoma A549 cell lines.

During our systematic study on the anticancer activities of Scutellaria barbata, scutebarbatine A (SBT-A), one of the major alkaloids in S. barbata, was found to have antitumor effects on A549 cells. Thus, we designed the present study to investigate in detail the antitumor effects of SBT-A. The cytotoxic effect of SBT-A on A549 in vitro were determined by an MTT assay and evaluated by IC50 values. Furthermore, results of Hoechst 33258 and Annexin V/PI staining assays demonstrated that SBT-A had significant antitumor effects on A549 cells via apoptosis, in a concentration-dependent manner. What's more, the mechanism was explored by western blotting, and our study revealed that SBT-A can up-regulate the expressions of cytochrome c, caspase-3 and 9, and down-regulate the levels of Bcl-2 in A549 cells. Finally, the antitumor effects of SBT-A were evaluated in vivo by using transplanted tumor nude mice, and the results confirmed that SBT-A has a notable antitumor effect on A549 cancer via mitochondria-mediated apoptosis. Collectively, our results demonstrated that SBT-A showed significant antitumor effects on A549 cells in vivo and in vitro via mitochondria-mediated apoptosis by up-regulating expressions of caspase-3 and 9, and down-regulating Bcl-2.

[Change in soil enzymes activities after adding biochar or straw by fluorescent microplate method].

The present work was aimed to study soil a-glucosidase and beta-glucosidase activities of and red soils based on fluorescence detection method combined with 96 microplates with TECAN Infinite 200 Multi-Mode Microplate Reader. We added biochar or straw (2.5 g air dry sample/50g air dry soil sample) into and red soils and the test was carried under fixed temperature and humidity condition (25 degrees C, 20% soil moisture content). The results showed that straw addition enhances soil alpha-glucosidase and beta-glucosidase activities, beta-glucosidase activity stimulated by rice straw treatment was higher than that of corn straw treatment, and activity still maintains strong after 40 days, accounting for increasing soil carbon transformation with straw inputting. Straw inputting increased soil nutrients contents and may promote microbial activity, which also lead to the increase oin enzyme Straw inputting increased soil nutrients contents and may promote microbial activity, which also lead to the increase oin enzyme activities. Different effects of straw kinds may be related to material source that needs further research. However, biochar inputting has little effect on soil alpha-glucosidase and beta-glucosidase activity. Biochar contains less available nutrients than straw and have degradation-resistant characteristics. Compared with the conventional spectrophotometric method, fluorescence microplate method is more sensitive to soil enzyme activities in suspension liquid, which can be used in a large number of samples. In brief, fluorescence microplate method is fast, accurate, and simple to determine soil enzymes activities.

Microdeletion on Xq27.1 in a Chinese VACTERL-Like Family with Kidney and Anal Anomalies.

Objective: VATER/VACTERL-like association is associated with adverse pregnancy outcomes. Genetic evidence of this disorder is sporadic. In this study, we aimed to provide genetic insights to improve the diagnosis of VACTERL. Methods: We have described a Chinese family in which four members were affected by renal defects or agenesis, anal atresia, and anovaginal fistula, which is consistent with the diagnosis of a VACTERL-like association. Pedigree and genetic analyses were conducted using genome and exome sequencing. Results: Segregation analysis revealed the presence of a recessive X-linked microdeletion in two living affected individuals, harboring a 196-380 kb microdeletion on Xq27.1, which was identified by familial exome sequencing. Genome sequencing was performed on the affected male, confirming a -196 kb microdeletion in Xq27.1, which included a 28% loss of the CDR-1 gene. Four family members were included in the co-segregation analysis, and only VACTERL-like cases with microdeletions were reported in X27.1. Conclusion: These results suggest that the 196-380 kb microdeletion in Xq27.1 could be a possible cause of the VATER/VACTERL-like association. However, further genetic and functional analyses are required to confirm or rule out genetic background as the definitive cause of the VACTERL association.

Clinical and molecular epidemiology of enterovirus D68 from 2013 to 2020 in Shanghai.

Enterovirus D68 (EV-D68) is an emerging pathogen that has caused outbreaks of severe respiratory disease worldwide, especially in children. We aim to investigate the prevalence and genetic characteristics of EV-D68 in children from Shanghai. Nasopharyngeal swab or bronchoalveolar lavage fluid samples collected from children hospitalized with community-acquired pneumonia were screened for EV-D68. Nine of 3997 samples were EV-D68-positive. Seven of nine positive samples were sequenced and submitted to GenBank. Based on partial polyprotein gene (3D) or complete sequence analysis, we found the seven strains belong to different clades and subclades, including three D1 (detected in 2013 and 2014), one D2 (2013), one D3 (2019), and two B3 (2014 and 2018). Overall, we show different clades and subclades of EV-D68 spread with low positive rates (0.2%) among children in Shanghai between 2013 and 2020. Amino acid mutations were found in the epitopes of the VP1 BC and DE loops and C-terminus; similarity analysis provided evidence for recombination as an important mechanism of genomic diversification. Both single nucleotide mutations and recombination play a role in evolution of EV-D68. Genetic instability within these clinical strains may indicate large outbreaks could occur following cumulative mutations.

A bimetallic (Ni/Co) metal-organic framework with excellent oxidase-like activity for colorimetric sensing of ascorbic acid.

A novel nanozyme of bimetallic (Ni/Co) metal-organic framework (Ni/Co-MOF) was synthesized using a simultaneous precipitation and acid etching method with a zeolitic imidazolate framework ZIF-67 as the template. The as-synthesized Ni/Co-MOF catalyst presented a three-dimensional hollow nanocage structure and exhibited excellent intrinsic oxidase-like activity. It was demonstrated that Ni/Co-MOF could directly catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue product (oxidized TMB, oxTMB) in the absence of H2O2. The mechanisms and kinetics of this nanozyme activity were investigated, and it was determined that the catalytic activity of Ni/Co-MOF was closely related to temperature and solution pH. Owing to its strong reducibility, ascorbic acid (AA) could reduce oxTMB, and the blue color of the reaction mixture faded over time. Therefore, a novel colorimetric platform was constructed to detect AA based on the oxidase-like activity of Ni/Co-MOF. Under optimal conditions, the absorbance of ox-TMB at 652 nm decreased linearly over the 0.015-50 µM AA range with a detection limit of 0.004 µM.

Strategy To Assess Zoonotic Potential Reveals Low Risk Posed by SARS-Related Coronaviruses from Bat and Pangolin.

In the last 2 decades, pathogens originating in animals may have triggered three coronavirus pandemics, including the coronavirus disease 2019 pandemic. Thus, evaluation of the spillover risk of animal severe acute respiratory syndrome (SARS)-related coronavirus (SARSr-CoV) is important in the context of future disease preparedness. However, there is no analytical framework to assess the spillover risk of SARSr-CoVs, which cannot be determined by sequence analysis alone. Here, we established an integrity framework to evaluate the spillover risk of an animal SARSr-CoV by testing how viruses break through key human immune barriers, including viral cell tropism, replication dynamics, interferon signaling, inflammation, and adaptive immune barriers, using human ex vivo lung tissues, human airway and nasal organoids, and human lung cells. Using this framework, we showed that the two pre-emergent animal SARSr-CoVs, bat BtCoV-WIV1 and pangolin PCoV-GX, shared similar cell tropism but exhibited less replicative fitness in the human nasal cavity or airway than did SARS-CoV-2. Furthermore, these viruses triggered fewer proinflammatory responses and less cell death, yet showed interferon antagonist activity and the ability to partially escape adaptive immune barriers to SARS-CoV-2. Collectively, these animal viruses did not fully adapt to spread or cause severe diseases, thus causing successful zoonoses in humans. We believe that this experimental framework provides a path to identifying animal coronaviruses with the potential to cause future zoonoses. IMPORTANCE Evaluation of the zoonotic risk of animal SARSr-CoVs is important for future disease preparedness. However, there are misconceptions regarding the risk of animal viruses. For example, an animal SARSr-CoV could readily infect humans. Alternately, human receptor usage may result in spillover risk. Here, we established an analytical framework to assess the zoonotic risk of SARSr-CoV by testing a series of virus-host interaction profiles. Our data showed that the pre-emergent bat BtCoV-WIV1 and pangolin PCoV-GX were less adapted to humans than SARS-CoV-2 was, suggesting that it may be extremely rare for animal SARSr-CoVs to break all bottlenecks and cause successful zoonoses.

[Analysis of the character of film decomposition of starch acetate (SA) coated urea by infrared spectrum].

The degradability characteristics of film with 4 kinds of starch acetate coated and inhibitors amended urea were analyzed by FTIR, which was purposed to supply theoretical basis for applying starch acetate coated urea fertilizers in farming. The result showed that the chemical component, molecule structure and material form of the membrane were not changed because of adding different inhibitors to urea. The main peaks of the film degradation process were brought by the H--O, --OH, CO2, C==O, --CH2, --CH3, C--O, C--O--H and C--O--C vibrancy in asymmetry and symmetry. In brown soil, the trend of absorbing value of the most high peak was 0>15>30>60>90>120>150>310 d. The infrared spectra of 4 kinds of fertilizers were not different remarkably, and the film was comparatively slowly degraded before 15 d. But a majority of the film had been already degraded after 150 days. The main components of film materials were degraded fastest in 310 days. The speed of film degradation wasn't more impacted by different inhibitors. The characteristic of starch acetate film degradation may be monitored entirely and degradation speed difference of the film could be represented through infrared spectrum.

[Analysis of the character of film decomposition of methyl methacrylate (MMA) coated urea by infrared spectrum].

The degradability characteristics of film with 4 kinds of methyl methacrylate coated urea amended with inhibitors were analyzed by FITR, which was purposed to supply theoretical basis for applying the FITR analysis method to film decomposition and methyl methacrylate coated urea fertilizers on farming. The result showed that the chemical component, molecule structure and material form of the membrane were not changed because of adding different inhibitors to urea. the main peaks of expressing film degradation process were brought by the -C-H of CH3 & CH2, -OH, C-O, C-C, C-O-C, C=O, C=C flexing vibrancy in asymmetry and symmetry in 3 479-3 195, 2 993--2 873, 1 741-1 564, 1 461-925 and 850-650 cm(-1). The peak value changed from smooth to tip, and from width to narrow caused by chemical structural transform of film The infrared spectrum of 4 kinds of fertilizers was not different remarkably before 60 days, and the film was slowly degraded. But degradation of the film was expedited after 60 days, it was most quickened at 120 day, and the decomposition rate of film was decreased at 310 day. The substantiality change of film in main molecule structure of 4 kinds of fertilizers didn't happen in 310 days. The main component of film materials was degraded most slowly in brown soil. The speed of film degradation wasn't heavily impacted by different inhibitors. The characteristic of film degradation may be monitored entirely by infrared spectrum. The degradation dynamic, chemical structure change, degradation speed difference of the film could be represented through infrared spectrum.

[Study of photosynthetic characteristics of transgenic barley based on reflectance of single leaf].

Analysis of leaf reflectance can provide a rich source of information about plant physiological process, surface properties of the leaf, as well as internal structure. In the present paper, the changes of reflectance spectra and spectral indices for transgenic barley and non-transgenic control variety based on measurements of single leaf were studied. The results showed that the ratio spectra that calculated by dividing one reflectance spectrum of transgenic barley by its' non-transgenic counterpart spectra were better to illustrate fine differences among spectra of leaves from different barley varieties. Ratio spectra varied between each pairs, but for most ratio spectrum indicated the reflectance differences between transgenic barley and non-transgenic counterpart were most obvious in the red spectrum around the chlorophyll peak and red edge (650-700 nm) and nearly identical in the green spectrum near 550 nm and within the near infrared region (beyond 750 nm). Across the entire calculated spectrum, the changes of reflectance within the region from 650 to 700 nm seem to be very sensitive to respond to possible unintended effects of genetic modification. Six published reflectance indices, the red edge (lambdaRE), the modified normalized difference vegetation index (mND), the structure-independent pigment index (SIPI), the ratio of reflectance in the red and green regions of the spectrum (R(Red)/R(Green)), the photochemical reflectance index (PRI) and the near-infrared reflectance at 800 nm (NIRR(800)) were used to make comparisons possible between species. The analyses of changes of these indices indicated that they were highly dependent on growth stages and barley varieties. Once indices described above have significant changes will mean that photosynthetic process, function and status of plants may be changed.

ACE2-independent infection of T lymphocytes by SARS-CoV-2.

SARS-CoV-2 induced marked lymphopenia in severe patients with COVID-19. However, whether lymphocytes are targets of viral infection is yet to be determined, although SARS-CoV-2 RNA or antigen has been identified in T cells from patients. Here, we confirmed that SARS-CoV-2 viral antigen could be detected in patient peripheral blood cells (PBCs) or postmortem lung T cells, and the infectious virus could also be detected from viral antigen-positive PBCs. We next prove that SARS-CoV-2 infects T lymphocytes, preferably activated CD4 + T cells in vitro. Upon infection, viral RNA, subgenomic RNA, viral protein or viral particle can be detected in the T cells. Furthermore, we show that the infection is spike-ACE2/TMPRSS2-independent through using ACE2 knockdown or receptor blocking experiments. Next, we demonstrate that viral antigen-positive T cells from patient undergone pronounced apoptosis. In vitro infection of T cells induced cell death that is likely in mitochondria ROS-HIF-1a-dependent pathways. Finally, we demonstrated that LFA-1, the protein exclusively expresses in multiple leukocytes, is more likely the entry molecule that mediated SARS-CoV-2 infection in T cells, compared to a list of other known receptors. Collectively, this work confirmed a SARS-CoV-2 infection of T cells, in a spike-ACE2-independent manner, which shed novel insights into the underlying mechanisms of SARS-CoV-2-induced lymphopenia in COVID-19 patients.

[Degradation characteristics of transgenic cotton residues in soil by Fourier transform infrared spectroscopy].

After transgenic cotton residues incubated in soil 430 d, the contents and structural characteristics of soil humus fractions, fulvic acid, humic acid and humin were measured by potassium dichromate titrimetric method and Fourier transform infrared spectroscopy. The results showed that all soil humus fractions increased after the degradation of cotton residues, and the most relative increase was with humin and the least was with fulvic acid. Compared to their near-isogenic non-transgenic cottons, soil humus content for transgenic Bt cotton residue decreased, and that forr transgenic Bt+CpTI cotton Z41 was approximate, but that for transgenic Bt+CpTI cotton SGK321 increased. Infrared spectroscopy of fulvic acid, humic acid and humin showed the addition of cotton residue decreased the content of oxygenous groups, and increased the alkyl and amide groups. There were differences in the speed to form soil humus among three transgenic cottons. Transgenic Bt cotton was slower than its counterpart, transgenic Bt+CpTI cotton Z41 was approximate to its counterpart, but transgenic Bt+CpTI cotton SGK321 was faster than its counterpart.

Construction of α-Amino Azines via Thianthrenation-Enabled Photocatalyzed Hydroarylation of Azine-Substituted Enamides with Arenes.

α-Amino azines are widely found in pharmaceuticals and ligands. Herein, we report a practical method for accessing this class of compounds via photocatalyzed hydroarylation of azine-substituted enamides with the in situ-generated aryl thianthrenium salts as the radical precursor. This reaction features a broad substrate scope, good functional group tolerance, and mild conditions and is suitable for the late-stage installation of α-amino azines in complex structures.