Uncovering genomic and transcriptional variations facilitates utilization of wild resources in cotton disease resistance improvement.

BACKGROUND: Upland cotton wild/landraces represent a valuable resource for disease resistance alleles. Genetic differentiation between genotypes, as well as variation in Verticillium wilt (VW) resistance, has been poorly characterized for upland cotton accessions on the domestication spectrum (from wild/landraces to elite lines). RESULTS: To illustrate the effects of modern breeding on VW resistance in upland cotton, 37 wild/landraces were resequenced and phenotyped for VW resistance. Genomic patterns of differentiation were identified between wild/landraces and improved upland cotton, and a significant decline in VW resistance was observed in association with improvement. Four genotypes representing different degrees of improvement were used in a full-length transcriptome analysis to study the genetic basis of VW resistance. ROS signaling was highly conserved at the transcriptional level, likely providing the basis for VW resistance in upland cotton. ASN biosynthesis and HSP90-mediated resistance moderated the response to VW in wild/landraces, and loss of induction activity of these genes resulted in VW susceptibility. The observed genomic differentiation contributed to the loss of induction of some important VW resistance genes such as HSP90.4 and PR16. CONCLUSIONS: Besides providing new insights into the evolution of upland cotton VW resistance, this study also identifies important resistance pathways and genes for both fundamental research and cotton breeding.

Fucosyltransferase 9 promotes neuronal differentiation and functional recovery after spinal cord injury by suppressing the activation of Notch signaling.

Individuals with spinal cord injury (SCI) suffer from permanent disabilities such as severe motor, sensory and autonomic dysfunction. Neural stem cell transplantation has proven to be a potential strategy to promote regeneration of the spinal cord, since NSCs can produce neurotrophic growth factors and differentiate into mature neurons to reconstruct the injured site. However, it is necessary to optimize the differentiation of NSCs before transplantation to achieve a better regenerative outcome. Inhibition of Notch signaling leads to a transition from NSCs to neurons, while the underlying mechanism remains inadequately understood. Our results demonstrate that overexpression of fucosyltransferase 9 (Fut9), which is upregulated by Wnt4, promotes neuronal differentiation by suppressing the activation of Notch signaling through disruption of furin-like enzyme activity during S1 cleavage. In an in vivo study, Fut9-modified NSCs efficiently differentiates into neurons to promote functional and histological recovery after SCI. Our research provides insight into the mechanisms of Notch signaling and a potential treatment strategy for SCI.

Application of telemedicine system on the management of general patient in quarantine.

To limit the epidemic of COVID-19, most countries and regions have adopted the policy of quarantine, providing an opportunity for the development of telemedicine. This study aims to develop a telemedicine system within a quarantined district and validate its effectiveness and safety in managing a variety of diseases within the population. Appling the private network and specialized set, telemedicine system and service process were constructed in the quarantine district. Based on the patients' conditions, the staffs supplied kinds of medical service for the patients in the quarantine district. The basic characteristics and results of patients in the quarantine area who used telemedicine system during January to September 2022 were statistically analyzed. Within this period, 2410 cases were included in this study, among which, 1803 patients directly saw a doctor by the Internet hospital in the Internet hospital of telemedicine system, 607 patients used telemedicine system, 166 patients achieved referral to a specific hospital via telemedicine system, and 162 cases made further consultation, with no infection cases in the quarantine zone and no death cases. The six most occurred diseases were respiratory disease (20.6%), ophthalmology and otorhinolaryngology (12.9%), cardiovascular diseases (12.7%), digestive system disease (12.5%), dermatological diseases (10.6%), and metabolic and endocrine diseases (7.6%). The top three referred cases were obstetric diseases (19.3%), others (12.0%) and respiratory disease (10.2%). There were statistically significant differences between the diseases of the cases using telemedicine system with and without referral (P < 0.001). It is feasible, effective and efficient to construct and use telemedicine system in quarantine area. It is an approach to manage many patients by indirectly contact. With the solution of follow-up related problems and the application of novel technologies, telemedicine may usher in greater development.

A pair of readers of bivalent chromatin mediate formation of Polycomb-based "memory of cold" in plants.

The Polycomb-group chromatin modifiers play important roles to repress or switch off gene expression in plants and animals. How the active chromatin state is switched to a Polycomb-repressed state is unclear. In Arabidopsis, prolonged cold induces the switching of the highly active chromatin state at the potent floral repressor FLC to a Polycomb-repressed state, which is epigenetically maintained when temperature rises to confer "cold memory," enabling plants to flower in spring. We report that the cis-acting cold memory element (CME) region at FLC bears bivalent marks of active histone H3K4me3 and repressive H3K27me3 that are read and interpreted by an assembly of bivalent chromatin readers to drive cold-induced switching of the FLC chromatin state. In response to cold, the 47-bp CME and its associated bivalent chromatin feature drive the switching of active chromatin state at a recombinant gene to a Polycomb-repressed domain, conferring cold memory. We reveal a paradigm for environment-induced chromatin-state switching at bivalent loci in plants.

Exercise combined with administration of adipose-derived stem cells ameliorates neuropathic pain after spinal cord injury.

Experimental studies have shown that exercise and human adipose-derived stem cells (ADSCs) play positive roles in spinal cord injury (SCI). However, whether ADSCs and/or exercise have a positive effect on SCI-induced neuropathic pain is still unclear. Thus, there is a need to explore the effects of exercise combined with administration of ADSCs on neuropathic pain after SCI. In this study, a thoracic 11 (T11) SCI contusion model was established in adult C57BL/6 mice. Exercise was initiated from 7 days post-injury and continued to 28 days post-injury, and approximately 1 × 105 ADSCs were transplanted into the T11 spinal cord lesion site immediately after SCI. Motor function and neuropathic pain-related behaviors were assessed weekly using the Basso Mouse Scale, von Frey filament test, Hargreaves method, and cold plate test. Histological studies (Eriochrome cyanine staining and immunohistochemistry) were performed at the end of the experiment (28 days post-injury). Exercise combined with administration of ADSCs partially improved early motor function (7, 14, and 21 days post-injury), mechanical allodynia, mechanical hypoalgesia, thermal hyperalgesia, and thermal hypoalgesia. Administration of ADSCs reduced white and gray matter loss at the lesion site. In addition, fewer microglia and astrocytes (as identified by expression of ionized calcium-binding adapter molecule 1 and glial fibrillary acidic protein, respectively) were present in the lumbar dorsal horn in the SCI + ADSCs and SCI + exercise + ADSCs groups compared with the sham group. Our findings suggest that exercise combined with administration of ADSCs is beneficial for the early recovery of motor function and could partially ameliorate SCI-induced neuropathic pain.

Transplantation of Wnt4-modified neural stem cells mediate M2 polarization to improve inflammatory micro-environment of spinal cord injury.

Neural stem cells (NSCs) transplantation has been considered as a potential strategy to reconnect the neural circuit after spinal cord injury (SCI) but the therapeutic effect was still unsatisfied because of the poor inflammatory micro-environment of SCI. Previous study reported that neuroprotection and inflammatory immunomodulation were considered to be most important mechanism of NSCs transplantation. In addition, Wnt4 has been considered to be neurogenesis and anti-inflammatory so that it would be an essential assistant agent for NSCs transplantation. Our single cells sequence indicates that macrophages are the most important contributor of inflammatory response after SCI and the interaction between macrophages and astrocytes may be the most crucial to inflammatory microenvironment of SCI. We further report the first piece of evidence to confirm the interaction between Wnt4-modified NSCs and macrophages using NSCs-macrophages co-cultured system. Wnt4-modified NSCs induce M2 polarization and inhibit M1 polarization of macrophages through suppression of TLR4/NF-κB signal pathway; furthermore, M2 cells promote neuronal differentiation of NSCs through MAPK/JNK signal pathway. In vivo, transplantation of Wnt4-modified NSCs improves inflammatory micro-environment through induce M2 polarization and inhibits M1 polarization of macrophages to promote axonal regeneration and tissue repair. The current study indicated that transplantation of Wnt4-modified NSCs mediates M2 polarization of macrophages to promote spinal cord injury repair. Our novel findings would provide more insight of SCI and help with identification of novel treatment strategy.

Meta-Analysis on the Anesthetic Effects of Remifentanil plus Dexmedetomidine versus Remifentanil Alone in Cardiac Surgery.

In this study, we performed a meta-analysis to investigate the anesthesia effects of remifentanil plus dexmedetomidine versus remifentanil alone in cardiac surgery. Literature search was performed on PubMed, Web of Science, Embase, China Knowledge Infrastructure, Wanfang Data, and other databases for relevant literature published in English or Chinese before October 2021. A total of 17 studies, consisting of 1350 patients, were included in this study. Of these, 10 studies showed that remifentanil plus dexmedetomidine had a good anesthesia effect in cardiac surgery (OR = 3.61, 95% CI: 1.73, 7.52, P < 0.001), and 8 studies showed that the Ramsay score test of anesthesia (SMD = 0.88; 95% CI: -0.77, 2.53; P < 0.001) in the experimental group was better than that in the control group. In addition, changes in the hemodynamic heart rate (SMD = -0.74; 95% CI: -1.41, -0.07; P < 0.001) and mean arterial pressure (SMD = -0.18; 95% CI: -0.72, 0.36; P < 0.001) of the two groups of anesthesia were counted in 17 studies, which also showed that the anesthesia effect of remifentanil plus dexmedetomidine was good. Thus, remifentanil plus dexmedetomidine may be a more promising option for cardiac surgery anesthesia than remifentanil alone.

WKYMVm/FPR2 Alleviates Spinal Cord Injury by Attenuating the Inflammatory Response of Microglia.

Spinal cord injury (SCI) is a common traumatic disease of the nervous system. The pathophysiological process of SCI includes primary injury and secondary injuries. An excessive inflammatory response leads to secondary tissue damage, which in turn exacerbates cellular and organ dysfunction. Due to the irreversibility of primary injury, current research on SCI mainly focuses on secondary injury, and the inflammatory response is considered the primary target. Thus, modulating the inflammatory response has been suggested as a new strategy for the treatment of SCI. In this study, microglial cell lines, primary microglia, and a rat SCI model were used, and we found that WKYMVm/FPR2 plays an anti-inflammatory role and reduces tissue damage after SCI by suppressing the extracellular signal-regulated kinases 1 and 2 (ERK1/2) and nuclear factor-κB (NF-κB) signaling pathways. FPR2 was activated by WKYMVm, suppressing the secretion of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) by inhibiting M1 microglial polarization. Moreover, FPR2 activation by WKYMVm could reduce structural disorders and neuronal loss in SCI rats. Overall, this study illustrated that the activation of FPR2 by WKYMVm repressed M1 microglial polarization by suppressing the ERK1/2 and NF-κB signaling pathways to alleviate tissue damage and locomotor decline after SCI. These findings provide further insight into SCI and help identify novel treatment strategies.

Giant photoinduced inverse spin Hall effect of the surface states in three dimensional topological insulators Bi2Te3 with different thickness.

The photoinduced inverse spin Hall effect (PISHE) has been studied in three dimensional (3D) topological insulator (TI) Bi2Te3 thin films with different thicknesses (3, 5, 12 and 20 quintuple layer (QL)). The sign of the PISHE current flips only once in the 3- and 20-QL Bi2Te3 films, but it flips three times in the 5-, 7- and 12-QL samples. The three-times sign flip is due to the superposition of the PISHE current of the top and bottom surface states in Bi2Te3 films. By analyzing the x-ray photoelectron spectroscopy (XPS) of the Bi2Te3 films, we find that the top surface of the 3- and 20-QL Bi2Te3 films are severely oxidized, leading to only one sign flip in the PISHE. The PISHE contributed by the top and bottom surface states in Bi2Te3 films have been successfully separated by fitting a theoretical model to the PISHE current. The impact of the bulk states on PISHE current has been determined. The PISHE current is also measured at different light powers, and all the measurement results are in good agreement with the theoretical model. In addition, it is found that the PISHE current in Bi2Te3 films grown on Si substrate is more than two orders larger than that grown on SrTiO3 substrates, which can be attributed to the larger absorption coefficient for Bi2Te3/Si samples. It is revealed that the PISHE current in 3D TI Bi2Te3 is as large as 140 nA/W in the 3-QL Bi2Te3 film grown on Si substrate, which is more than one order larger than that reported in GaAs/AlGaAs heterojunction (about 2 nA/W) and GaN/AlGaN heterojunction (about 1.7 nA/W). The giant PISHE current demonstrates that the TIs with strong SOC may have good application prospects in spintronic devices with high spin-to-charge conversion efficiency.

Current-Induced Spin Photocurrent in GaAs at Room Temperature.

Circularly polarized photocurrent, observed in p-doped bulk GaAs, varies nonlinearly with the applied bias voltage at room temperature. It has been explored that this phenomenon arises from the current-induced spin polarization in GaAs. In addition, we found that the current-induced spin polarization direction of p-doped bulk GaAs grown in the (001) direction lies in the sample plane and is perpendicular to the applied electric field, which is the same as that in GaAs quantum well. This research indicates that circularly polarized photocurrent is a new optical approach to investigate the current-induced spin polarization at room temperature.

Molecular basis of CONSTANS oligomerization in FLOWERING LOCUS T activation.

The transcription factor CONSTANS (CO) integrates day-length information to induce the expression of florigen FLOWERING LOCUS T (FT) in Arabidopsis. We recently reported that the C-terminal CCT domain of CO forms a complex with NUCLEAR FACTOR-YB/YC to recognize multiple cis-elements in the FT promoter, and the N-terminal tandem B-box domains form a homomultimeric assembly. However, the mechanism and biological function of CO multimerization remained unclear. Here, we report that CO takes on a head-to-tail oligomeric configuration via its B-boxes to mediate FT activation in long days. The crystal structure of B-boxesCO reveals a closely connected tandem B-box fold forming a continuous head-to-tail assembly through unique CDHH zinc fingers. Mutating the key residues involved in CO oligomerization resulted in a non-functional CO, as evidenced by the inability to rescue co mutants. By contrast, a transgene encoding a human p53-derived tetrameric peptide in place of the B-boxesCO rescued co mutant, emphasizing the essential role of B-boxesCO -mediated oligomerization. Furthermore, we found that the four TGTG-bearing cis-elements in FT proximal promoter are required for FT activation in long days. Our results suggest that CO forms a multimer to bind to the four TGTG motifs in the FT promoter to mediate FT activation.

Structural insights into the multivalent binding of the Arabidopsis FLOWERING LOCUS T promoter by the CO-NF-Y master transcription factor complex.

Flowering plants sense various environmental and endogenous signals to trigger the floral transition and start the reproductive growth cycle. CONSTANS (CO) is a master transcription factor in the photoperiod floral pathway that integrates upstream signals and activates the florigen gene FLOWERING LOCUS T (FT). Here, we performed comprehensive structural and biochemical analyses to study the molecular mechanism underlying the regulation of FT by CO in Arabidopsis thaliana. We show that the four previously characterized cis-elements in the FT promoter proximal region, CORE1, CORE2, P1, and P2, are all direct CO binding sites. Structural analysis of CO in complex with NUCLEAR FACTOR-YB/YC (NF-YB/YC) and the CORE2 or CORE1 elements revealed the molecular basis for the specific recognition of the shared TGTG motifs. Biochemical analysis suggested that CO might form a homomultimeric assembly via its N-terminal B-Box domain and simultaneously occupy multiple cis-elements within the FT promoter. We suggest that this multivalent binding gives the CO-NF-Y complex high affinity and specificity for FT promoter binding. Overall, our data provide a detailed molecular model for the regulation of FT by the master transcription factor complex CO-NF-Y during the floral transition.

Control of Circular Photogalvanic Effect of Surface States in the Topological Insulator Bi2Te3 via Spin Injection.

The circular photogalvanic effect (CPGE) provides a method utilizing circularly polarized light to control spin photocurrent and will also lead to novel opto-spintronic devices. The CPGE of three-dimensional topological insulator Bi2Te3 with different substrates and thicknesses has been systematically investigated. It is found that the CPGE current can be dramatically tuned by adopting different substrates. The CPGE current of the Bi2Te3 films on Si substrates are more than two orders larger than that on SrTiO3 substrates when illuminated by 1064 nm light, which can be attributed to the modulation effect due to the spin injection from Si substrate to Bi2Te3 films, larger light absorption coefficient, and stronger inequivalence between the top and bottom surface states for Bi2Te3 films grown on Si substrates. The excitation power dependence of the CPGE current of Bi2Te3 films on Si substrates shows a saturation at high power especially for thicker samples, whereas that on SrTiO3 substrates almost linearly increases with excitation power. Temperature dependence of the CPGE current of Bi2Te3 films on Si substrates first increases and then decreases with decreasing temperature, whereas that on SrTiO3 substrates changes monotonously with temperature. These interesting phenomena of the CPGE current of Bi2Te3 films on Si substrates are related to the spin injection from Si substrates to Bi2Te3 films. Our work not only intrigues new physics but also provides a method to effectively manipulate the helicity-dependent photocurrent via spin injection.

Genetic and Epigenetic Understanding of the Seasonal Timing of Flowering.

The developmental transition to flowering in many plants is timed by changing seasons, which enables plants to flower at a season that is favorable for seed production. Many plants grown at high latitudes perceive the seasonal cues of changing day length and/or winter cold (prolonged cold exposure), to regulate the expression of flowering-regulatory genes through the photoperiod pathway and/or vernalization pathway, and thus align flowering with a particular season. Recent studies in the model flowering plant Arabidopsis thaliana have revealed that diverse transcription factors engage various chromatin modifiers to regulate several key flowering-regulatory genes including FLOWERING LOCUS C (FLC) and FLOWERING LOCUS T (FT) in response to seasonal signals. Here, we summarize the current understanding of molecular and chromatin-regulatory or epigenetic mechanisms underlying the vernalization response and photoperiodic control of flowering in Arabidopsis. Moreover, the conservation and divergence of regulatory mechanisms for seasonal flowering in crops and other plants are briefly discussed.

HISTONE DEACETYLASE 9 Functions with Polycomb Silencing to Repress FLOWERING LOCUS C Expression.

Polycomb repressive complex 2 (PRC2) catalyzes repressive histone 3 Lys-27 trimethylation (H3K27me3) to mediate genome-wide transcriptional repression in plants and animals. PRC2 controls various developmental processes in plants and plays a critical role in the developmental transition to flowering. FLOWERING LOCUS C (FLC), first identified in Arabidopsis (Arabidopsis thaliana), is a potent floral repressor in crucifers and some other plants that is subjected to complex regulation. Here, we show that HISTONE DEACETYLASE 9 (HDA9)-mediated H3K27 deacetylation is required for PRC2-mediated H3K27me3 in Arabidopsis. We further demonstrate that through physical association with the epigenome readers VP1/ABI3-LIKE 1 (VAL1) and VAL2, which recognize a cis-regulatory element at the FLC locus, HDA9 and PRC2 function in concert to mediate H3K27 deacetylation and subsequent trimethylation at this residue. This leads to FLC repression in the rapid-cycling Arabidopsis accessions. Our study uncovers roles for HDA9 in PRC2-mediated H3K27me3, FLC repression, and flowering-time regulation.

Observation of Extrinsic Photo-Induced Inverse Spin Hall Effect in a GaAs/AlGaAs Two-Dimensional Electron Gas.

The inverse spin Hall effect induced by circularly polarized light has been observed in a GaAs/AlGaAs two-dimensional electron gas. The spin transverse force has been determined by fitting the photo-induced inverse spin Hall effect (PISHE) current to a theoretical model. The PISHE current is also measured at different light power and different light spot profiles, and all the measurement results are in good agreement with the theoretical calculations. We also measure the PISHE current at different temperatures (i.e., from 77 to 300 K). The temperature dependence of the PISHE current indicates that the extrinsic mechanism plays a dominant role, which is further confirmed by the weak dependence of the PISHE current on the crystal orientation of the sample.

Inverse spin Hall effect induced by linearly polarized light in the topological insulator Bi2Se3.

The inverse spin Hall effect (ISHE) induced by the normal incidence of linearly-polarized infrared radiation has been observed in the topological insulator Bi2Se3. A model has been proposed to explain the phenomenon, and the spin transverse force has been determined by the model fitting. The anomalous linear photogalvanic effect (ALPGE) is also observed, and the photoinduced momentum anisotropy is extracted. Furthermore, the ISHE and ALPGE are investigated at different temperatures between 77 and 300 K, and the temperature dependence of the spin transverse force and photoinduced momentum anisotropy are obtained. This study suggests a new way to investigate the inverse spin Hall effect via linearly polarized light even at room temperature.

Photoinduced Inverse Spin Hall Effect of Surface States in the Topological Insulator Bi2Se3.

The three-dimensional (3D) topological insulator (TI) Bi2Se3 exhibits topologically protected, linearly dispersing Dirac surface states (SSs). To access the intriguing properties of these SSs, it is important to distinguish them from the coexisting two-dimensional electron gas (2DEG) on the surface. Here, we use circularly polarized light to induce the inverse spin Hall effect in a Bi2Se3 thin film at different temperatures (i.e., from 77 to 300 K). It is demonstrated that the photoinduced inverse spin Hall effect (PISHE) of the top SSs and the 2DEG can be separated based on their opposite signs. The temperature and power dependence of the PISHE also confirms our method. Furthermore, it is found that the PISHE in the 2DEG is dominated by the extrinsic mechanism, as revealed by the temperature dependence of the PISHE.

Some results on random smoothness.

Based on the analysis of stratification structure on random normed modules, we first present the notion of random smoothness in random normed modules. Then, we establish the relations between random smoothness and random strict convexity. Finally, a type of Gâteaux differentiability is defined for random norms, and its relation to random smoothness is given. The results are helpful in the further study of geometry of random normed modules.