A rapid and highly efficient sorghum transformation strategy using GRF4-GIF1/ternary vector system.

Sorghum is an important crop for food, forage, wine and biofuel production. To enhance its transformation efficiency without negative developmental by-effects, we investigated the impact of GRF4-GIF1 chimaera and GRF5 on sorghum transformation. Both GRF4-GIF1 and GRF5 effectively improved the transformation efficiency of sorghum and accelerated the transformation process of sorghum to less than 2 months which was not observed when using BBM-WUS. As agrobacterium  effectors increase the ability of T-DNA transfer into plant cells, we checked whether ternary vector system can additively enhance sorghum transformation. The combination of GRF4-GIF1 with helper plasmid pVS1-VIR2 achieved the highest transformation efficiency, reaching 38.28%, which is 7.71-fold of the original method. Compared with BBM-WUS, overexpressing GRF4-GIF1 caused no noticeable growth defects in sorghum. We further developed a sorghum CRISPR/Cas9 gene-editing tool based on this GRF4-GIF1/ternary vector system, which achieved an average gene mutation efficiency of 41.36%, and null mutants were created in the T0 generation.

Adsorption of tetracycline from aqueous solution by ZIF-8: Isotherms, kinetics and thermodynamics.

In this study, ZIF-8 nanoparticles were synthesized using a simple method at room temperature. The ZIF-8 nanoparticles were then characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET (Brunauer-Emmett-Teller) specific surface area, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and zeta potential. Subsequent batch adsorption experiments evaluated the adsorption performance of ZIF-8 on tetracycline, examining key pa-rameters like reaction time, pH, temperature, and adsorbent dosage. The results revealed a removal rate for TC of up to 90.59%. The adsorption data aligned with the Sips model, showcasing a maximum adsorption capacity of 359.61 mg/g at 303K. Further, the adsorption kinetics adhered to the pseudo-second-order kinetic model with an equilibrium adsorption capacity of 90 mg/g at 303K. The considerable specific surface area of ZIF-8, standing at 1674.169 m2/g, likely enhances the adsorption efficacy. Analysis using XRD and FTIR confirmed the adsorption of TC on the ma-terial's surface. Overall, the predominant driving forces behind the adsorption process were identified as electrostatic interactions and π-π stacking interactions.

The UBC27-AIRP3 ubiquitination complex modulates ABA signaling by promoting the degradation of ABI1 in Arabidopsis.

Abscisic acid (ABA) is the key phytohormone in plant drought tolerance and stress adaptation. The clade A protein phosphatase 2Cs (PP2Cs) like ABI1 (ABA-INSENSITIVE 1) work as coreceptors of ABA and regulate multiple ABA responses. Ubiquitination of ABI1 has been proven to play important regulatory roles in ABA signaling. However, the specific ubiquitin conjugating enzyme (E2) involved is unknown. Here, we report that UBC27 is an active E2 that positively regulates ABA signaling and drought tolerance. UBC27 forms the E2-E3 pair with the drought regulator RING E3 ligase AIRP3. Both UBC27 and AIRP3 interact with ABI1 and affect the ubiquitination and degradation of ABI1. ABA activates the expression of UBC27, inhibits the proteasome degradation of UBC27, and enhances the interaction between UBC27 and ABI1 to increase its activity. These findings uncover a regulatory mechanism in ABA signaling and drought response and provide a further understanding of the plant ubiquitination system and ABA signaling pathway.

GLABRA2-based selection efficiently enriches Cas9-generated nonchimeric mutants in the T1 generation.

The CRISPR/Cas9 system is a widely used tool for genome editing in plants. In Arabidopsis (Arabidopsis thaliana), egg cell-specific promoters driving Cas9 expression have been applied to reduce the proportion of T1 transformants that are chimeras; however, this approach generally leads to relatively low mutagenesis rates. In this study, a GLABRA2 mutation-based visible selection (GBVS) system was established to enrich nonchimeric mutants among T1 plants generated by an egg cell-specific CRISPR/Cas9 system. GBVS generally enhanced mutation screening, increasing the frequency by 2.58- to 7.50-fold, and 25%-48.15% of T1 plants selected through the GBVS system were homozygous or biallelic mutants, which was 1.71- to 7.86-fold higher than the percentage selected using the original system. The mutant phenotypes of T2 plants were not obviously affected by the glabrous background for all four target genes used in this study. Additionally, the nonchimeric pyrabactin resistance 1 (PYR1)/PYR1-like 1 (PYL1) and PYL2 triple mutant pyr1/pyl1/pyl2 could be obtained in the T1 generation with a ratio of 26.67% when GBVS was applied. Collectively, our results show that compared with the known CRISPR/Cas9 systems, the GBVS system described here saves more time and labor when used for the obtainment of homozygous or biallelic monogenic mutants and nonchimeric polygenic mutants in Arabidopsis.

A Detection and Tracking Method Based on Heterogeneous Multi-Sensor Fusion for Unmanned Mining Trucks.

There exist many difficulties in environmental perception in transportation at open-pit mines, such as unpaved roads, dusty environments, and high requirements for the detection and tracking stability of small irregular obstacles. In order to solve the above problems, a new multi-target detection and tracking method is proposed based on the fusion of Lidar and millimeter-wave radar. It advances a secondary segmentation algorithm suitable for open-pit mine production scenarios to improve the detection distance and accuracy of small irregular obstacles on unpaved roads. In addition, the paper also proposes an adaptive heterogeneous multi-source fusion strategy of filtering dust, which can significantly improve the detection and tracking ability of the perception system for various targets in the dust environment by adaptively adjusting the confidence of the output target. Finally, the test results in the open-pit mine show that the method can stably detect obstacles with a size of 30-40 cm at 60 m in front of the mining truck, and effectively filter out false alarms of concentration dust, which proves the reliability of the method.

The Promising Nanovectors for Gene Delivery in Plant Genome Engineering.

Highly efficient gene delivery systems are essential for genetic engineering in plants. Traditional delivery methods have been widely used, such as Agrobacterium-mediated transformation, polyethylene glycol (PEG)-mediated delivery, biolistic particle bombardment, and viral transfection. However, genotype dependence and other drawbacks of these techniques limit the application of genetic engineering, particularly genome editing in many crop plants. There is a great need to develop newer gene delivery vectors or methods. Recently, nanomaterials such as mesoporous silica particles (MSNs), AuNPs, carbon nanotubes (CNTs), and layer double hydroxides (LDHs), have emerged as promising vectors for the delivery of genome engineering tools (DNA, RNA, proteins, and RNPs) to plants in a species-independent manner with high efficiency. Some exciting results have been reported, such as the successful delivery of cargo genes into plants and the generation of genome stable transgenic cotton and maize plants, which have provided some new routines for genome engineering in plants. Thus, in this review, we summarized recent progress in the utilization of nanomaterials for plant genetic transformation and discussed the advantages and limitations of different methods. Furthermore, we emphasized the advantages and potential broad applications of nanomaterials in plant genome editing, which provides guidance for future applications of nanomaterials in plant genetic engineering and crop breeding.

Antiviral strategies: What can we learn from natural reservoirs?

Viruses cause many severe diseases in both plants and animals, urging us to explore new antiviral strategies. In their natural reservoirs, viruses live and replicate while causing mild or no symptoms. Some animals, such as bats, are the predicted natural reservoir of multiple viruses, indicating that they possess broad-spectrum antiviral capabilities. Mechanisms of host defenses against viruses are generally studied independently in plants and animals. In this article, we speculate that some antiviral strategies of natural reservoirs are conserved between kingdoms. To verify this hypothesis, we created null mutants of 10-formyltetrahydrofolate synthetase (AtTHFS), an Arabidopsis thaliana homologue of methylenetetrahydrofolate dehydrogenase, cyclohydrolase and formyltetrahydrofolate synthetase 1 (MTHFD1), which encodes a positive regulator of viral replication in bats. We found that disruption of AtTHFS enhanced plant resistance to three different types of plant viruses, including the tomato spotted wilt virus (TSWV), the cucumber mosaic virus (CMV) and the beet severe curly top virus (BSCTV). These results demonstrate a novel antiviral strategy for plant breeding. We further discuss the approaches used to identify and study natural reservoirs of plant viruses, especially those hosting many viruses, and highlight the possibility of discovering new antiviral strategies from them for plant molecular breeding and antiviral therapy.

Serum Monokine Induced by Gamma Interferon Is Associated With Severity of Coronary Artery Disease.

The immune system may play important roles in the pathogenesis of cardiovascular disease. T-cell mediated immune responses in human progression of atherosclerotic disease and hypertension have recently been revealed, but the significance of T-cell specific chemokines in coronary artery heart disease has not been confirmed. In our study, we sought to examine the association between serum levels of the monokine induced by gamma interferon (MIG)/CXCL9 and the severity of coronary artery disease. We studied 117 patients with coronary heart disease and 80 patients with no coronary heart disease. The severity of coronary artery disease was assessed via coronary artery angiography and the Gensini score was calculated. Clinical and biochemical indices, including serum levels of MIG, CD40L, and IFN-γ were analyzed in all subjects. Finally, we found there was a significant correlation between serum MIG levels and the severity of coronary artery disease, quantified by the Gensini score (r = 0.122, P = 0.009). Furthermore, multivariate regression analysis revealed that serum MIG levels were independently associated with the severity of coronary artery disease, quantified by the Gensini score (ß = 0.100, P = 0.021). Our findings could indicate the potential clinical implication of MIG with respect to early coronary artery atherosclerosis in humans.

Transfer of orbital angular momentum through sub-wavelength waveguides.

Data capacity of optical communication is achieving its limit owing to the non-linear effect of optical fiber. As an effective alternative, light carrying orbital angular momentum can greatly increase the capacity for its unprecedented degree of freedom. We demonstrate the propagation of orbital angular momentum with topological charge of 1 and 2 in plasmonic circular waveguide with sub-wavelength diameter with little propagation loss of 2.73 dB/µm, which has never been observed in optical fibers with sub-wavelength diameter. We also confirm that lights carrying orbital angular momentum can be maintained in sharp bended sub-wavelength waveguide. This plasmonic waveguide may serve as a key component in on-chip systems involving OAM.

Optical phased array radiating optical vortex with manipulated topological charges.

Optical antennas are key elements in quantum optics emitting and sensing, and behave wide range applications in optical domain. However, integration of optical antenna radiating orbital angular momentum is still a challenge in nano-scale. We theoretically demonstrate a sub-wavelength phased optical antenna array, which manipulates the distribution of the orbital angular momentum in the near field. Orbital angular momentum with topological charge of 4 can be obtained by controlling the phase distribution of the fundamental mode orbital angular momentum in each antenna element. Our results indicate this phased array may be utilized in high integrated optical communication systems.

[Comparison of the outcomes of microscopic varicocelectomy and laparoscopic varicocelectomy].

OBJECTIVE: To compare and analyze semen quality improvement between the patients with microscopic varicocelectomy and laparoscopic varicocelectomy. METHODS: A total of 291 patients with varicocele were included in this study, of whom 176 underwent microscopic varicocelectomy and 115 laparoscopic varicocelectomy. The improvement rates of semen quality and pregnancy rates between the two groups were compared. RESULTS: The improvement rate of sperm density in microscopic group was significantly higher than that of laparoscopic group (87.6% vs. 73.7%, P = 0.006). Spouse pregnancy rate of microscopic group was significantly higher than that of laparoscopic group (45.4% vs. 30.3%, P = 0.017). CONCLUSION: The effect of microscopic varicocelectomy was superior to that of laparoscopic varicocelectomy.

Time series single-cell transcriptional atlases reveal cell fate differentiation driven by light in Arabidopsis seedlings.

Light serves as the energy source for plants as well as a signal for growth and development during their whole life cycle. Seedling de-etiolation is the most dramatic manifestation of light-regulated plant development processes, as massive reprogramming of the plant transcriptome occurs at this time. Although several studies have reported about organ-specific development and expression induced by light, a systematic analysis of cell-type-specific differentiation and the associated transcriptional regulation is still lacking. Here we obtained single-cell transcriptional atlases for etiolated, de-etiolating and light-grown Arabidopsis thaliana seedlings. Informative cells from shoot and root tissues were grouped into 48 different cell clusters and finely annotated using multiple markers. With the determination of comprehensive developmental trajectories, we demonstrate light modulation of cell fate determination during guard cell specialization and vasculature development. Comparison of expression atlases between wild type and the pifq mutant indicates that phytochrome-interacting factors (PIFs) are involved in distinct developmental processes in endodermal and stomatal lineage cells via controlling cell-type-specific expression of target genes. These results provide information concerning the light signalling networks at the cell-type resolution, improving our understanding of how light regulates plant development at the cell-type and genome-wide levels. The obtained information could serve as a valuable resource for comprehensively investigating the molecular mechanism of cell development and differentiation in response to light.

Establishment of an Efficient Genome Editing System in Lettuce Without Sacrificing Specificity.

The efficiency of the CRISPR/Cas9 genome editing system remains limited in many crops. Utilizing strong promoters to boost the expression level of Cas9 are commonly used to improve the editing efficiency. However, these strategies also increase the risk of off-target mutation. Here, we developed a new strategy to utilize intron-mediated enhancement (IME)-assisted 35S promoter to drive Cas9 and sgRNA in a single transcript, which escalates the editing efficiency by moderately enhancing the expression of both Cas9 and sgRNA. In addition, we developed another strategy to enrich cells highly expressing Cas9/sgRNA by co-expressing the developmental regulator gene GRF5, which has been proved to ameliorate the transformation efficiency, and the transgenic plants from these cells also exhibited enhanced editing efficiency. This system elevated the genome editing efficiency from 14-28% to 54-81% on three targets tested in lettuce (Lactuca sativa) without increasing the off-target editing efficiency. Thus, we established a new genome editing system with highly improved on-target editing efficiency and without obvious increasement in off-target effects, which can be used to characterize genes of interest in lettuce and other crops.

A simple and efficient strategy to produce transgene-free gene edited plants in one generation using paraquat resistant 1 as a selection marker.

Introduction: DNA integration is a key factor limiting the marketing of CRISPR/Cas9-mediated gene edited crops. Several strategies have been established to obtain transgene-free gene edited plants; however, these strategies are usually time-consuming, technically difficult, providing low mutagenesis efficiency, and/or including a narrow host range. Method: To overcome such issues, we established a paraquat resistant 1 (PAR1)-based positive screening (PARS) strategy, which achieved efficient screening of transgene-free gene edited plants. Results: With PARS, the screening efficiency of mutant increased by 2.81-fold on average, and approximately 10% of T1 plants selected via PARS were transgenefree. Moreover, heritable transgene-free mutations at target loci were identified in the T1 generation. Discussion: Based on the previous reports and our data, we know that paraquat is toxic to all green plants, PAR1 is conserved among all plant species tested, and the transient expression of Cas9 editor can produce transgene-free gene edited plants. Thus, we assume that the PARS strategy established here has the potential to be widely used to screen transgene-free mutants in various crops using diverse CRISPR/Cas9 delivery approaches.

Efficient genetic transformation and CRISPR/Cas9-mediated genome editing of watermelon assisted by genes encoding developmental regulators.

Cucurbitaceae is an important family of flowering plants containing multiple species of important food plants, such as melons, cucumbers, squashes, and pumpkins. However, a highly efficient genetic transformation system has not been established for most of these species (Nanasato and Tabei, 2020). Watermelon (Citrullus lanatus), an economically important and globally cultivated fruit crop, is a model species for fruit quality research due to its rich diversity of fruit size, shape, flavor, aroma, texture, peel and flesh color, and nutritional composition (Guo et al., 2019). Through pan-genome sequencing, many candidate loci associated with fruit quality traits have been identified (Guo et al., 2019). However, few of these loci have been validated. The major barrier is the low transformation efficiency of the species, with only few successful cases of genetic transformation reported so far (Tian et al., 2017; Feng et al., 2021; Wang JF et al., 2021; Wang YP et al., 2021). For example, Tian et al. (2017) obtained only 16 transgenic lines from about 960 cotyledon fragments, yielding a transformation efficiency of 1.67%. Therefore, efficient genetic transformation could not only facilitate the functional genomic studies in watermelon as well as other horticultural species, but also speed up the transgenic and genome-editing breeding.

Regulation of Ubiquitination Is Central to the Phosphate Starvation Response.

As sessile organisms, plants have developed numerous strategies to overcome the limiting availability of the essential nutrient phosphate in nature. Recent studies reveal that post-translational modification (PTM) by ubiquitination is an important and central regulation mechanism in the plant phosphate starvation response (PSR). Ubiquitination precisely modulates the stability and trafficking of proteins in response to the heterogeneous phosphate supplement. Induction of autophagy provides novel insights into the molecular mechanisms under phosphate starvation. In this review, we present and discuss novel findings on the regulation of diverse PSRs through ubiquitination. Resolving these regulation mechanisms will pave the way to improve phosphate acquisition and utilization efficiency in crops.

Dynamical beam manipulation based on 2-bit digitally-controlled coding metasurface.

Recently, a concept of digital metamaterials has been proposed to manipulate field distribution through proper spatial mixtures of digital metamaterial bits. Here, we present a design of 2-bit digitally-controlled coding metasurface that can effectively modulate the scattered electromagnetic wave and realize different far-field beams. Each meta-atom of this metasurface integrates two pin diodes, and by tuning their operating states, the metasurface has four phase responses of 0, π/2, π, and 3π/2, corresponding to four basic digital elements "00", "01", "10", and "11", respectively. By designing the coding sequence of the above digital element array, the reflected beam can be arbitrarily controlled. The proposed 2-bit digital metasurface has been demonstrated to possess capability of achieving beam deflection, multi-beam and beam diffusion, and the dynamical switching of these different scattering patterns is completed by a programmable electric source.

Multi-spectral Metasurface for Different Functional Control of Reflection Waves.

Metasurface have recently generated much interest due to its strong manipulation of electromagnetic wave and its easy fabrication compared to bulky metamaterial. Here, we propose the design of a multi-spectral metasurface that can achieve beam deflection and broadband diffusion simultaneously at two different frequency bands. The metasurface is composed of two-layered metallic patterns backed by a metallic ground plane. The top-layer metasurface utilizes the cross-line structures with two different dimensions for producing 0 and π reflection phase response, while the bottom-layer metasurface is realized by a topological morphing of the I-shaped patterns for creating the gradient phase distribution. The whole metasurface is demonstrated to independently control the reflected waves to realize different functions at two bands when illuminated by a normal linear-polarized wave. Both simulation and experimental results show that the beam deflection is achieved at K-band with broadband diffusion at X-Ku band.

Dynamical manipulation of electromagnetic polarization using anisotropic meta-mirror.

Polarization control of electromagnetic wave is very important in many fields. Here, we propose an active meta-mirror to dynamically manipulate electromagnetic polarization state at a broad band. This meta-mirror is composed of a double-layered metallic pattern backed by a metallic flat plate, and the active elements of PIN diodes are integrated into the meta-atom to control the reflection phase difference between two orthogonal polarization modes. Through switching the operating state of the PIN diodes, the meta-mirror is expected to achieve three polarization states which are left-handed, right-handed circular polarizations and linear polarization, respectively. We fabricated this active meta-mirror and validated its polarization conversion performance by measurement. The linearly polarized incident wave can be dynamically converted to right-handed or left-handed circular polarization in the frequency range between 3.4 and 8.8 GHz with the average loss of 1 dB. Furthermore, it also can keep its initial linear polarization state.

Combining the absorptive and radiative loss in metasurfaces for multi-spectral shaping of the electromagnetic scattering.

The absorptive and radiative losses are two fundamental aspects of the electromagnetic responses, which are widely occurring in many different systems such as waveguides, solar cells, and antennas. Here we proposed a metasurface to realize the control of the absorptive and radiative loss and to reduce the radar cross section (RCS) in multi-frequency bands. The anti-phase gradient and absorptive metasurfaces were designed that consists of metallic square patch and square loop structure inserted with resistors, acting as an phase gradient material in the X and Ku band, while behaving as an absorber in the S band. The simulation and experiment results verified the double-band, wideband and polarization-independent RCS reduction by the absorptive and anti-phase gradient metasurfaces.