Cross-modality interaction in sensory perception is advantageous for animals’ survival. How cortical sensory processing is cross-modally modulated and what are the underlying neural circuits remain ...poorly understood. In mouse primary visual cortex (V1), we discovered that orientation selectivity of layer (L)2/3, but not L4, excitatory neurons was sharpened in the presence of sound or optogenetic activation of projections from primary auditory cortex (A1) to V1. The effect was manifested by decreased average visual responses yet increased responses at the preferred orientation. It was more pronounced at lower visual contrast and was diminished by suppressing L1 activity. L1 neurons were strongly innervated by A1-V1 axons and excited by sound, while visual responses of L2/L3 vasoactive intestinal peptide (VIP) neurons were suppressed by sound, both preferentially at the cell’s preferred orientation. These results suggest that the cross-modality modulation is achieved primarily through L1 neuron- and L2/L3 VIP-cell-mediated inhibitory and disinhibitory circuits.
•Layer (L)5 neurons in A1 project directly to superficial layers of V1•Sound sharpens orientation selectivity of V1 L2/L3 pyramidal neurons•V1 L1 neurons, strongly innervated by A1 axons, mediate the sharpening effect•Visual responses of V1 L2/L3 VIP neurons are differentially suppressed by sound
Cross-modality interaction in sensory perception is advantageous for animals’ survival. Ibrahim et al. show that sound concurrent with visual stimuli sharpens orientation selectivity of primary visual cortical principal neurons, achieved through auditory cortex projections to layer 1 of visual cortex.
The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using ...short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa.
A major challenge in modern rice production is to achieve the dual goals of high yield and good quality with low environmental costs. This study was designed to determine whether optimized nitrogen ...(N) fertilization could fulfill these multiple goals. In two-year experiments, two high yielding 'super' rice cultivars were grown with different N fertilization management regimes, including zero N input, local farmers' practice (LFP) with heavy N inputs, and optimized N fertilization (ONF). In ONF, by reducing N input, increasing planting density, and optimizing the ratio of urea application at different stages, N use efficiency and the physicochemical and textural properties of milled rice were improved at higher yield levels. Compared with LFP, yield and partial factor productivity of applied N (PFP) under ONF were increased (on average) by 1.70 and 13.06％, respectively. ONF increased starch and amylose content, and significantly decreased protein content. The contents of the short chains of A chain (degree of polymerization (DP) 6–12) and B1 chain (DP 13–25) of amylopectin were significantly increased under ONF, which resulted in a decrease in the stability of rice starch crystals. ONF increased viscosity values and improved the thermodynamic properties of starch, which resulted in better eating and cooking quality of the rice. Thus, ONF could substantially compensate the negative effects caused by N fertilizer and achieve the multiple goals of higher grain quality and nitrogen use efficiency (NUE) at high yield levels. These results will be useful for applications of high quality rice production at high yield levels.
Increasing evidence has shown that cancer stem cells or tumor initiating cells are the 'root cause' of malignant cancers. However, the exact origin of cancer stem cells still remains obscure in ...thyroid research. EMT has been implicated in the initiation and conversion of early-stage tumors into invasive malignancies and is associated with the stemness of cancer cells. Based on these facts, a new hypothesis was suggested that EMT induces cancer stem cell generation and tumor progression in human thyroid cancer cells in vitro. In the present study, FTC133 cells identified as EMT-negative cells were used for EMT induction by HIF‑1α transfection. Overexpression of HIF-1α induced FTC133 cells to undergo EMT, downregulated the epithelial markers E-cadherin, upregulated the mesenchymal marker vimentin, and associated with highly invasive and metastatic properties. Most importantly, the induction of EMT promoted the stem-like side population cell proportion in the FTC133 cells. These results indicate that EMT induction promotes CSC traits and cell proportions in the thyroid cancer cells, which implies that EMT could induce cancer stem cell generation and tumor progression in thyroid cancers. Further understanding of the role of EMT and cancer stem cells in cancer progression may reveal new targets for the prevention or therapy of thyroid cancers.
Cortical sensory processing is modulated by behavioral and cognitive states. How this modulation is achieved by changing synaptic circuits remains largely unknown. In awake mouse auditory cortex, we ...found that sensory-evoked spike responses of layer 2/3 (L2/3) excitatory cells were scaled down with preserved sensory tuning when mice transitioned from quiescence to active behaviors, including locomotion, whereas L4 and thalamic responses were unchanged. Whole-cell voltage-clamp recordings revealed that tone-evoked synaptic excitation and inhibition exhibited a robust functional balance. The change to active states caused scaling down of excitation and inhibition at approximately equal levels in L2/3 cells, but resulted in no synaptic changes in L4 cells. This lamina-specific gain control could be attributed to an enhancement of L1-mediated inhibitory tone, with L2/3 parvalbumin inhibitory neurons also being suppressed. Thus, L2/3 circuits can adjust the salience of output in accordance with momentary behavioral demands while maintaining the sensitivity and quality of sensory processing.
Sucrose phosphate synthase (SPS) is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase (SPP) for sucrose synthesis, and it plays an essential role in energy ...provisioning during growth and development in plants as well as improving fruit quality. However, studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking. In the present study, a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1. The gene structures and their promoter cis-elements, protein conserved motifs, subcellular localizations, physiological functions and biochemical properties were analyzed. A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication (WGD) and segmental duplication played vital roles in MdSPS gene family expansion. The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication. Furthermore, three SPS gene subfamilies were classified based on phylogenetic relationships, and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies. In addition, a major gene related to sucrose accumulation (MdSPSA2.3) was identified according to the highly consistent trends in the changes of its expression in four apple varieties (‘Golden Delicious’, ‘Fuji’, ‘Qinguan’ and ‘Honeycrisp’) and the correlation between gene expression and soluble sugar content during fruit development. Furthermore, the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit. The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.
An online survey conducted March 18–19, 2020 on the official China CDC WeChat account platform was used to evaluate the effect of public education about masks usage during the new coronavirus disease ...2019 (COVID-19) epidemic. Chinese nationals older than 18 were eligible for the survey. The survey collected 5,761 questionnaires from the 31 provinces, municipalities, and autonomous regions of mainland China. 99.7% and 97.2% of the respondents answered correctly that respiratory droplets and direct contact were the main transmission routes. 73.3% of the respondents considered COVID-19 to be ‘serious’ or ‘very serious’. When going to the hospital, 96.9% (2,885/2,976 had gone to a hospital) used a mask during the COVID-19 epidemic, while 41.1% (2,367/5,761) did not use a mask before the epidemic. Among the respondents that used public transportation and went shopping, 99.6% and 99.4%, respectively, wore masks. Among respondents who returned to work, 75.5% wore a mask at the workplace, while 86.3% of those who have not returned to work will choose to use masks when they return to the workplace. The Chinese public is highly likely to use a mask during COVID-19 epidemic, and the mask usage changed greatly since the COVID-19 outbreak. Therefore, public education has played an important role during the COVID-19 epidemic.
ABSTRACT
Mitochondrial retrograde regulation (MRR) is the transduction of mitochondrial signals to mediate nuclear gene expression. It is not clear whether MRR is a common regulation mechanism in ...plant abiotic stress response. In this study, we analysed the early abiotic stress response of the rice OsAOX1 genes, and the induction of OsAOX1a and OsAOX1b (OsAOX1a/b) was selected as a working model for the stress‐induced MRR studies. We found that the induction mediated by the superoxide ion (O2·‐)‐generating chemical methyl viologen was stronger than that of hydrogen peroxide (H2O2). The addition of reactive oxygen species (ROS) scavengers demonstrated that the stress induction was reduced by eliminating O2·‐. Furthermore, the stress induction did not rely on chloroplast‐ or cytosol‐derived O2·‐. Next, we generated transgenic plants overexpressing the superoxide dismutase (SOD) gene at different subcellular locations. The results suggest that only the mitochondrial SOD, OsMSD, attenuated the stress induction of OsAOX1a/b specifically. Therefore, our findings demonstrate that abiotic stress initiates the MRR on OsAOX1a/b and that mitochondrial O2·– is involved in the process.
Mitochondrial retrograde regulation (MRR) is the transduction of mitochondrial signals to mediate nuclear gene expression. Here, we showed the stress induction of MRR model gene AOX1 could be attenuated by a Mitochondrial superoxide dismutase in rice. Our results suggested the plants could initiate MRR in response to abiotic stress.
A central goal of genetics is to understand the links between genetic variation and disease. Intuitively, one might expect disease-causing variants to cluster into key pathways that drive disease ...etiology. But for complex traits, association signals tend to be spread across most of the genome—including near many genes without an obvious connection to disease. We propose that gene regulatory networks are sufficiently interconnected such that all genes expressed in disease-relevant cells are liable to affect the functions of core disease-related genes and that most heritability can be explained by effects on genes outside core pathways. We refer to this hypothesis as an “omnigenic” model.
Many complex genetic traits arise from large numbers of variants, each with small effects. This Perspective argues that risk is ultimately driven by an even larger number of genes with no direct impact on the phenotype or disease whose effects are propagated through regulatory networks.
•The carbonation resistance of fly ash (FA) & blast furnace slag (BFS)-based geopolymer (GP) concrete were investigated in detail by theoretical analysis and the accelerated carbonation ...test.•Carbonation rates of the ambient cured GP concrete and GP mortar were modeled by power functions.•The influencing factors of carbonation rate of GP concrete were clarified, including retarder addition, BFS’s ratio and fineness, NaOH content, and curing temperature, etc.•The relationship between carbonation resistance and compressive strength of GP concrete was discussed.
For putting geopolymer (GP) to practical use in reinforced concrete, the carbonation resistance of GP concrete should be clarified. In this study, the carbonation depths of various GP concrete and GP mortar, of which the aluminosilicate materials were fly ash (FA) and ground blast furnace slag (BFS), were measured by the accelerated carbonation test at different elapsed times. The relationship between the carbonation depth and the elapsed time were further examined based on the experimental results and by theoretical analysis. A root function was proposed to describe the carbonation rate of FA&BFS-based GP concrete. Finally, the influencing factors of carbonation resistance of FA&BFS-based GP concrete were discussed through a comparison of carbonation rate coefficients. It is mainly concluded that the carbonation resistance of FA&BFS-based GP concrete cured at room temperature is lower than usual concrete using Ordinary Portland Cement (OPC). The carbonation resistance increases with the increase of BFS ratio in active fillers (AF), NaOH content in active activator solution (AS), and BFS fineness, or with the decrease of AS/AF ratio, and water/AF ratio. Moreover, heat curing and the use of the retarder are benefit to the carbonation resistance of FA&BFS-based GP concrete.
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