Genome-Wide Identification of the 14-3-3 Gene Family and Its Involvement in Salt Stress Response through Interaction with NsVP1 in Nitraria sibirica Pall.

14-3-3 proteins are widely distributed in eukaryotic cells and play an important role in plant growth, development, and stress tolerance. This study revealed nine 14-3-3 genes from the genome of Nitraria sibirica Pall., a halophyte with strong salt tolerance. The physicochemical properties, multiple sequence alignment, gene structure and motif analysis, and chromosomal distributions were analyzed, and phylogenetic analysis, cis-regulatory elements analysis, and gene transcription and expression analysis of Ns14-3-3s were conducted. The results revealed that the Ns14-3-3 gene family consists of nine members, which are divided into two groups: ε (four members) and non-ε (five members). These members are acidic hydrophilic proteins. The genes are distributed randomly on chromosomes, and the number of introns varies widely among the two groups. However, all genes have similar conserved domains and three-dimensional protein structures. The main differences are found at the N-terminus and C-terminus. The promoter region of Ns14-3-3s contains multiple cis-acting elements related to light, plant hormones, and abiotic stress responses. Transcriptional profiling and gene expression pattern analysis revealed that Ns14-3-3s were expressed in all tissues, although with varying patterns. Under salt stress conditions, Ns14-3-3 1a, Ns14-3-3 1b, Ns14-3-3 5a, and Ns14-3-3 7a showed significant changes in gene expression. Ns14-3-3 1a expression decreased in all tissues, Ns14-3-3 7a expression decreased by 60% to 71% in roots, and Ns14-3-3 1b expression increased by 209% to 251% in stems. The most significant change was observed in Ns14-3-3 5a, with its expression in stems increasing by 213% to 681%. The yeast two-hybrid experiments demonstrated that Ns14-3-3 5a interacts with NsVP1 (vacuolar H+-pyrophosphatase). This result indicates that Ns14-3-3 5a may respond to salt stress by promoting ionic vacuole compartmentalization in stems and leaves through interactions with NsVP1. In addition, N. sibirica has a high number of stems, allowing it to compartmentalize more ions through its stem and leaf. This may be a contributing factor to its superior salt tolerance compared to other plants.

Design and Fabrication of Stretchable Microwave Transmission Lines Based on a Quasi-Microstrip Structure.

Radio frequency (RF) electronics are vital components of stretchable electronics that require wireless capabilities, ranging from skin-interfaced wearable systems to implantable devices to soft robotics. One of the key challenges in stretchable electronics is achieving near-lossless transmission line technology that can carry high-frequency electrical signals between various RF components. Almost all existing stretchable interconnection strategies only demonstrate direct current or low-frequency electrical properties, limiting their use in high frequencies, especially in the MHz to GHz range. Here, we describe the design and fabrication of a simple stretchable RF transmission line strategy that integrates a quasi-microstrip structure into a stretchable serpentine microscale interconnection. We show the effects of quasi-microstrip structural dimensions on the RF performance based on detailed quantitative analysis and experimentally demonstrate the optimized device capable of carrying RF signals with frequencies of up to 40 GHz with near-lossless characteristics. To show the potential application of our transmission line in stretchable microwave electronics, we designed a single-stage power amplifier system with a gain of 9.8 dB at 9 GHz that fully utilizes our quasi-microstrip transmission line technology.

ALDH2 activation attenuates oxygen–glucose deprivation/reoxygenation-induced cell apoptosis, pyroptosis, ferroptosis and autophagy

Purpose It is previously reported that aldehyde dehydrogenase 2 family member (ALDH2) shows neuroprotective effects in cerebral ischemia/reperfusion injury. However, whether the protective effects are through mediating the programmed cell death is yet to be fully elucidated. Methods In vitro oxygen–glucose deprivation/reoxygenation (OGD/R) model was established in HT22 cells and mouse cortical neurons. Subsequently, ALDH2 expression were assessed by qRT-PCR and western blot. The methylation status was examined by methylation-specific PCR (MS-PCR). Then, ALDH2 expression was promoted and suppressed to explore the role of ALDH2 in OGD/R-treated cells. CCK-8 assay was applied to detect cell viability, and flow cytometry was applied to evaluate cell apoptosis. Western blot was applied to detect the apoptosis-related proteins (Caspase 3, Bcl-2 and Bax), necroptosis-related proteins (RIP3 and MLKL), pyroptosis-related proteins (NLRP3 and GSDMD), ferroptosis-related protein (ACSL4 and GPX4), and autophagy-related proteins (LC3B, and p62). IL-1β and IL-18 production was evaluated by ELISA assay. Reactive oxygen species production and Fe2+ content were evaluated by the corresponding detection kit. Results In OGD/R-treated cells, ALDH2 expression was decreased, which was due to the hypermethylation of ALDH2 in the promoter region. ALDH2 overexpression improved cell viability and ALDH2 knockdown suppressed cell viability in OGD/R-treated cells. We also found that ALDH2 overexpression attenuated OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy, while ALDH2 knockdown facilitated the OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy. Conclusions Collectively, our results implied that ALDH2 attenuated OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy to promote cell viability in HT22 cells and mouse cortical neurons (AU)

ALDH2 activation attenuates oxygen-glucose deprivation/reoxygenation-induced cell apoptosis, pyroptosis, ferroptosis and autophagy.

PURPOSE: It is previously reported that aldehyde dehydrogenase 2 family member (ALDH2) shows neuroprotective effects in cerebral ischemia/reperfusion injury. However, whether the protective effects are through mediating the programmed cell death is yet to be fully elucidated. METHODS: In vitro oxygen-glucose deprivation/reoxygenation (OGD/R) model was established in HT22 cells and mouse cortical neurons. Subsequently, ALDH2 expression were assessed by qRT-PCR and western blot. The methylation status was examined by methylation-specific PCR (MS-PCR). Then, ALDH2 expression was promoted and suppressed to explore the role of ALDH2 in OGD/R-treated cells. CCK-8 assay was applied to detect cell viability, and flow cytometry was applied to evaluate cell apoptosis. Western blot was applied to detect the apoptosis-related proteins (Caspase 3, Bcl-2 and Bax), necroptosis-related proteins (RIP3 and MLKL), pyroptosis-related proteins (NLRP3 and GSDMD), ferroptosis-related protein (ACSL4 and GPX4), and autophagy-related proteins (LC3B, and p62). IL-1ß and IL-18 production was evaluated by ELISA assay. Reactive oxygen species production and Fe2+ content were evaluated by the corresponding detection kit. RESULTS: In OGD/R-treated cells, ALDH2 expression was decreased, which was due to the hypermethylation of ALDH2 in the promoter region. ALDH2 overexpression improved cell viability and ALDH2 knockdown suppressed cell viability in OGD/R-treated cells. We also found that ALDH2 overexpression attenuated OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy, while ALDH2 knockdown facilitated the OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy. CONCLUSIONS: Collectively, our results implied that ALDH2 attenuated OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy to promote cell viability in HT22 cells and mouse cortical neurons.

Integrated metabolome and transcriptome analysis unveils novel pathway involved in the fruit coloration of Nitraria tangutorum Bobr.

BACKGROUND: The desert shrub Nitraria tangutorum Bobr. is important for its resistance to salt and alkali in Northwest China. It is an ecologically important species in this region and provides edible and medicinal berries. This study showed a mutant of N. tangutorum (named Jincan, JC) that has a strong yellow pericarp vs red in a wild type (represented by NT). RESULTS: In this study, the secondary metabolic and molecular mechanisms responsible for Nitraria fruit coloration were investigated using LC-MS-based widely targeted metabolomics and transcriptomics data. As a result of our study, 122 and 104 flavonoid metabolites were differentially expressed throughout the mature and transition stages between JC and NT, respectively. Furthermore, two cyanidin derivatives (cyanidin 3-O-glucoside and cyanidin-3-O-(2''-O-glucosyl) glucoside) and one pelargonidin derivative (pelargonidin-3-O-glucoside) were identified only in the NT phenotype. The functional genes F3H (flavanone 3-hydroxylase), F3'H (flavonoid 3'-hydroxylase) and UFGT (flavonoid 3-O-glucosyltransferase) and the transcription factors MYB, bHLH, NAC and bZIP were significantly downregulated in JC. Meanwhile, the activity of UFGT was extremely low in both periods of JC, with a five-fold higher enzymatic activity of UFGT in RT than in YT. In summary, due to the lack of catalysis of UGFT, yellow fruit of JC could not accumulate sufficient cyanidin and pelargonidin derivatives during fruit ripening. CONCLUSION: Taken together, our data provide insights into the mechanism for the regulation of anthocyanin synthesis and N. tangutorum fruit coloration and provide a theoretical basis to develop new strategies for developing bioactive compounds from N. tangutorum fruits.

Selection and validation of appropriate reference genes for RT-qPCR analysis of Nitraria sibirica under various abiotic stresses.

BACKGROUND: Nitraria sibirica Pall. is a halophytic shrub with strong environmental adaptability that can survive in extremely saline-alkali and drought-impacted environments. Gene expression analysis aids in the exploration of the molecular mechanisms of plant responses to abiotic stresses. RT-qPCR is the most common technique for studying gene expression. Stable reference genes are a prerequisite for obtaining accurate target gene expression results in RT-qPCR analysis. RESULTS: In this study, a total of 10 candidate reference genes were selected from the transcriptome of N. sibirica, and their expression stability in leaves and roots under different treatment conditions (salt, alkali, drought, cold, heat and ABA) was evaluated with the geNorm, NormFinder, BestKeeper, comparative ΔCt and RefFinder programs. The results showed that the expression stability of the candidate reference genes was dependent on the tissue and experimental conditions tested. ACT7 combined with R3H, GAPDH, TUB or His were the most stable reference genes in the salt- or alkali-treated leaves, salt-treated roots and drought-treated roots, respectively; R3H and GAPDH were the most suitable combination for drought-treated leaves, heat-treated root samples and ABA-treated leaves; DIM1 and His maintained stable expression in roots under alkali stress; and TUB combined with R3H was stable in ABA-treated roots. TBCB and GAPDH exhibited stable expression in heat-treated leaves; TBCB, R3H, and ERF3A were stable in cold-treated leaves; and the three most stable reference genes for cold-treated roots were TBCB, ACT11 and DIM1. The reliability of the selected reference genes was further confirmed by evaluating the expression patterns of the NsP5CS gene under the six treatment conditions. CONCLUSION: This study provides a theoretical reference for N. sibirica gene expression standardization and quantification under various abiotic stress conditions and will help to reveal the molecular mechanisms that confer stress tolerance to N. sibirica.

Populus euphratica Phospholipase Dδ Increases Salt Tolerance by Regulating K+/Na+ and ROS Homeostasis in Arabidopsis.

Phospholipase Dα (PLDα), which produces signaling molecules phosphatidic acid (PA), has been shown to play a critical role in plants adapting to salt environments. However, it is unclear whether phospholipase Dδ (PLDδ) can mediate the salt response in higher plants. PePLDδ was isolated from salt-resistant Populus euphratica and transferred to Arabidopsis thaliana to testify the salt tolerance of transgenic plants. The NaCl treatment (130 mM) reduced the root growth and whole-plant fresh weight of wild-type (WT) A. thaliana, vector controls (VC) and PePLDδ-overexpressed lines, although a less pronounced effect was observed in transgenic plants. Under salt treatment, PePLDδ-transgenic Arabidopsis exhibited lower electrolyte leakage, malondialdehyde content and H2O2 levels than WT and VC, resulting from the activated antioxidant enzymes and upregulated transcripts of genes encoding superoxide dismutase, ascorbic acid peroxidase and peroxidase. In addition, PePLDδ-overexpressed plants increased the transcription of genes encoding the plasma membrane Na+/H+ antiporter (AtSOS1) and H+-ATPase (AtAHA2), which enabled transgenic plants to proceed with Na+ extrusion and reduce K+ loss under salinity. The capacity to regulate reactive oxygen species (ROS) and K+/Na+ homeostasis was associated with the abundance of specific PA species in plants overexpressing PePLDδ. PePLDδ-transgenic plants retained a typically higher abundance of PA species, 34:2 (16:0-18:2), 34:3 (16:0-18:3), 36:4 (18:2-18:2), 36:5 (18:2-18:3) and 36:6 (18:3-18:3), under control and saline conditions. It is noteworthy that PA species 34:2 (16:0-18:2), 34:3 (16:0-18:3), 36:4 (18:2-18:2) and 36:5 (18:2-18:3) markedly increased in response to NaCl in transgenic plants. In conclusion, we suppose that PePLDδ-derived PA enhanced the salinity tolerance by regulating ROS and K+/Na+ homeostasis in Arabidopsis.

Full-Length Transcriptome Analysis of the Halophyte Nitraria sibirica Pall.

BACKGROUND: Nitraria sibirica Pall. is one of the pioneer tree species in saline-alkali areas due to its extreme salt tolerance. However, the lack of information on its genome limits the further exploration of the molecular mechanisms in N. sibirica under salt stress. METHODS: In this study, we used single-molecule real-time (SMRT) technology based on the PacBio Iso-Seq platform to obtain transcriptome data from N. sibirica under salt treatment for the first time, which is helpful for our in-depth analysis of the salt tolerance and molecular characteristics of N. sibirica. RESULTS: Our results suggested that a total of 234,508 circular consensus sequences (CCSs) with a mean read length of 2121 bp were obtained from the 19.26 Gb raw data. Furthermore, based on transcript cluster analysis, 93,713 consensus isoforms were obtained, including 92,116 high-quality isoforms. After removing redundant sequences, 49,240 non-redundant transcripts were obtained from high-quality isoforms. A total of 37,261 SSRs, 1816 LncRNAs and 47,314 CDSs, of which 40,160 carried complete ORFs, were obtained. Based on our transcriptome data, we also analyzed the coding genes of H+-PPase, and the results of both bioinformatics and functional analyses indicated that the gene prediction via full-length transcripts obtained by SMRT technology is reliable and effective. In summary, our research data obtained by SMRT technology provides more reliable and accurate information for the further analysis of the regulatory network and molecular mechanism of N. sibirica under salt stress.

Ectomycorrhizal Fungal Strains Facilitate Cd2+ Enrichment in a Woody Hyperaccumulator under Co-Existing Stress of Cadmium and Salt.

Cadmium (Cd2+) pollution occurring in salt-affected soils has become an increasing environmental concern in the world. Fast-growing poplars have been widely utilized for phytoremediation of soil contaminating heavy metals (HMs). However, the woody Cd2+-hyperaccumulator, Populus × canescens, is relatively salt-sensitive and therefore cannot be directly used to remediate HMs from salt-affected soils. The aim of the present study was to testify whether colonization of P. × canescens with ectomycorrhizal (EM) fungi, a strategy known to enhance salt tolerance, provides an opportunity for affordable remediation of Cd2+-polluted saline soils. Ectomycorrhization with Paxillus involutus strains facilitated Cd2+ enrichment in P. × canescens upon CdCl2 exposures (50 µM, 30 min to 24 h). The fungus-stimulated Cd2+ in roots was significantly restricted by inhibitors of plasmalemma H+-ATPases and Ca2+-permeable channels (CaPCs), but stimulated by an activator of plasmalemma H+-ATPases. NaCl (100 mM) lowered the transient and steady-state Cd2+ influx in roots and fungal mycelia. Noteworthy, P. involutus colonization partly reverted the salt suppression of Cd2+ uptake in poplar roots. EM fungus colonization upregulated transcription of plasmalemma H+-ATPases (PcHA4, 8, 11) and annexins (PcANN1, 2, 4), which might mediate Cd2+ conductance through CaPCs. EM roots retained relatively highly expressed PcHAs and PcANNs, thus facilitating Cd2+ enrichment under co-occurring stress of cadmium and salinity. We conclude that ectomycorrhization of woody hyperaccumulator species such as poplar could improve phytoremediation of Cd2+ in salt-affected areas.

Populus euphratica Apyrases Increase Drought Tolerance by Modulating Stomatal Aperture in Arabidopsis.

Stomatal regulation is crucial to reduce water consumption under drought conditions. Extracellular ATP (eATP) serves as a signaling agent in stomatal regulation; however, it is less known whether the eATP mediation of stomatal aperture is linked to apyrases (APYs), the principal enzymes that control the concentration of eATP. To clarify the role of APYs in stomatal control, PeAPY1 and PeAPY2 were isolated from Populus euphratica and transferred into Arabidopsis. Compared with the wild-type Arabidopsis and loss-of-function mutants (Atapy1 and Atapy2), PeAPY1- and PeAPY2-transgenic plants decreased stomatal aperture under mannitol treatment (200 mM, 2 h) and reduced water loss during air exposure (90 min). The role of apyrase in stomatal regulation resulted from its control in eATP-regulated stomatal movements and increased stomatal sensitivity to ABA. The bi-phasic dose-responses to applied nucleotides, i.e., the low ATP (0.3-1.0 mM)-promoted opening and high ATP (>2.0 mM)-promoted closure, were both restricted by P. euphratica apyrases. It is noteworthy that eATP at a low concentration (0.3 mM) counteracted ABA action in the regulation of stomatal aperture, while overexpression of PeAPY1 or PeAPY2 effectively diminished eATP promotion in opening, and consequently enhanced ABA action in closure. We postulate a speculative model of apyrase signaling in eATP- and ABA-regulated stomatal movements under drought.

S- to X-Band Stretchable Inductors and Filters for Gigahertz Soft and Epidermal Electronics.

To fulfill the increasing demand for radiofrequency (RF) wireless communication capacity for epidermal electronics, stretchable integrated circuits (ICs) in the gigahertz (GHz) range are desirable. Lumped RF inductors, as a key component in RFICs, typically dominate a large portion of the circuit/chip area and therefore make such inductors mechanically stretchable is critical for GHz-frequency stretchable RFICs. Most of the reported stretchable inductors operate in the MHz frequency range. The only GHz stretchable inductor shows a quality factor of about 2, limiting its potential RF applications. Here, stretchable inductors with a high quality factor of Q > 12.6 and resonance operation frequency of fres > 11.6 GHz are demonstrated by combining microspirals with stretchable structures, overcoming all of the shortcomings of previous demonstrations. Furthermore, a stretchable 1.5-2.6 GHz filter with a peak insertion loss of -2.3 dB at 1.8 GHz is developed, showing negligible performance changes under stretching or on the skin to demonstrate the utility in practical wireless applications like GSM and Bluetooth (2.45 GHz) bands. The demonstrations can facilitate multiple GHz epidermal RFICs in the future.

Antioxidant Enzymatic Activity and Osmotic Adjustment as Components of the Drought Tolerance Mechanism in Carex duriuscula.

Drought stress is a major environmental constraint for plant growth. Climate-change-driven increases in ambient temperatures resulted in reduced or unevenly distributed rainfalls, leading to increased soil drought. Carex duriuscula C. A. Mey is a typical drought-tolerant sedge, but few reports have examined the mechanisms conferring its tolerant traits. In the present study, the drought responses of C. duriuscula were assessed by quantifying activity of antioxidant enzymes in its leaf and root tissues and evaluating the relative contribution of organic and inorganic osmolyte in plant osmotic adjustment, linking it with the patterns of the ion acquisition by roots. Two levels of stress-mild (MD) and severe (SD) drought treatments-were used, followed by re-watering. Drought stress caused reduction in a relative water content and chlorophyll content of leaves; this was accompanied by an increase in the hydrogen peroxide (H2O2) and superoxide (O2-) contents in leaves and roots. Under MD stress, the activities of catalase (CAT), peroxidase (POD), and glutathione peroxidase (GPX) increased in leaves, whereas, in roots, only CAT and POD activities increased. SD stress led to an increase in the activities of CAT, POD, superoxide dismutase (SOD), and GPX in both tissues. The levels of proline, soluble sugars, and soluble proteins in the leaves also increased. Under both MD and SD stress conditions, C. duriuscula increased K+, Na+, and Cl- uptake by plant roots, which resulted in an increased K+, Na+, and Cl- concentrations in leaves and roots. This reliance on inorganic osmolytes enables a cost-efficient osmotic adjustment in C. duriuscula. Overall, this study revealed that C. duriuscula was able to survive arid environments due to an efficient operation of its ROS-scavenging systems and osmotic adjustment mechanisms.

Tissue tolerance mechanisms conferring salinity tolerance in a halophytic perennial species Nitraria sibirica Pall.

Plant salt tolerance relies on a coordinated functioning of different tissues and organs. Salinity tissue tolerance is one of the key traits that confer plant adaptation to saline environment. This trait implies maintenance low cytosolic Na+/K+ ratio in metabolically active cellular compartments. In this study, we used Nitraria sibirica Pall., a perennial woody halophyte species, to understand the mechanistic basis of its salinity tissue tolerance. The results showed that the growth of seedlings was stimulated by 100-200 mM NaCl treatment. The ions distribution analysis showed that the leaves act as an Na+ sink, while the plant roots possess superior K+ retention. The excessive Na+ absorbed from the soil was mainly transported to the shoot and was eventuallysequestrated into mesophyll vacuoles in the leaves. As a result, N. sibirica could keep the optimal balance of K+/Na+ at a tissue- and cell-specific level under saline condition. To enable this, N. sibirica increased both vacuolar H+-ATPase and H+-PPase enzymes activities and up-regulated the expressions of NsVHA, NsVP1 and NsNHX1 genes. Vacuolar Na+ sequestration in the leaf mesophyll, mediated by NsVHA, NsVP1 and NsNHX1, reduced the Na+ concentration in cytosol and inhibited further K+ loss. Meanwhile, N. sibirica enhanced the Two Pore K+ expression at the transcriptional level to promote K+ efflux from vacuole into cytoplasm, assisting in maintaining cytosolic K+ homeostasis. It is concluded that the tissue tolerance traits such as vacuolar Na+ sequestration and intracellular K+ homeostasis are critical to confer adaptation of N. sibirica to soil salinity.

Populus euphratica annexin1 facilitates cadmium enrichment in transgenic Arabidopsis.

Phytoremediation offers a great potential for affordable remediation of heavy metal (HM)-polluted soil and water. Screening and identifying candidate genes related to HM uptake and transport is prerequisite for improvement of phytoremediation by genetic engineering. Using the cadmium (Cd)-hypersensitive Populus euphratica, an annexin encoding gene facilitating Cd enrichment was identified in this study. With a 12 h exposure to CdCl2 (50-100 µM), P. euphratica cells down-regulated transcripts of annexin1 (PeANN1). PeANN1 was homologue to Arabidopsis annexin1 (AtANN1) and localized mainly to the plasma membrane (PM) and cytosol. Compared with wild type and Atann1 mutant, PeANN1 overexpression in Arabidopsis resulted in a more pronounced decline in survival rate and root length after a long-term Cd stress (10 d, 50 µM), due to a higher cadmium accumulation in roots. PeANN1-transgenic roots exhibited enhanced influx conductance of Cd2+ under cadmium shock (30 min, 50 µM) and short-term stress (12 h, 50 µM). Noteworthy, the PeANN1-facilitated Cd2+ influx was significantly inhibited by a calcium-permeable channel (CaPC) inhibitor (GdCl3) but was promoted by 1 mM H2O2, indicating that Cd2+ entered root cells via radical-activated CaPCs in the PM. Therefore, PeANN1 can serve as a candidate gene for improvement of phytoremediation by genetic engineering.

A Salt-Signaling Network Involving Ethylene, Extracellular ATP, Hydrogen Peroxide, and Calcium Mediates K+/Na+ Homeostasis in Arabidopsis.

This work aimed at investigating the interactive effects of salt-signaling molecules, i.e., ethylene, extracellular ATP (eATP), H2O2, and cytosolic Ca2+ ([Ca2+]cyt), on the regulation of K+/Na+ homeostasis in Arabidopsisthaliana. The presence of eATP shortened Col-0 hypocotyl length under no-salt conditions. Moreover, eATP decreased relative electrolyte leakage and lengthened root length significantly in salt-treated Col-0 plants but had no obvious effects on the ethylene-insensitive mutants etr1-1 and ein3-1eil1-1. Steady-state ionic flux kinetics showed that exogenous 1-aminocyclopropane-1-carboxylic acid (ACC, an ethylene precursor) and eATP-Na2 (an eATP donor) significantly increased Na+ extrusion and suppressed K+ loss during short-term NaCl treatment. Moreover, ACC remarkably raised the fluorescence intensity of salt-elicited H2O2 and cytosolic Ca2+. Our qPCR data revealed that during 12 h of NaCl stress, application of ACC increased the expression of AtSOS1 and AtAHA1, which encode the plasma membrane (PM) Na+/H+ antiporters (SOS1) and H+-ATPase (H+ pumps), respectively. In addition, eATP markedly increased the transcription of AtEIN3, AtEIL1, and AtETR1, and ACC treatment of Col-0 roots under NaCl stress conditions caused upregulation of AtRbohF and AtSOS2/3, which directly contribute to the H2O2 and Ca2+ signaling pathways, respectively. Briefly, ethylene was triggered by eATP, a novel upstream signaling component, which then activated and strengthened the H2O2 and Ca2+ signaling pathways to maintain K+/Na+ homeostasis under salinity.

Heterogeneously integrated flexible microwave amplifiers on a cellulose nanofibril substrate.

Low-cost flexible microwave circuits with compact size and light weight are highly desirable for flexible wireless communication and other miniaturized microwave systems. However, the prevalent studies on flexible microwave electronics have only focused on individual flexible microwave elements such as transistors, inductors, capacitors, and transmission lines. Thinning down supporting substrate of rigid chip-based monolithic microwave integrated circuits has been the only approach toward flexible microwave integrated circuits. Here, we report a flexible microwave integrated circuit strategy integrating membrane AlGaN/GaN high electron mobility transistor with passive impedance matching networks on cellulose nanofibril paper. The strategy enables a heterogeneously integrated and, to our knowledge, the first flexible microwave amplifier that can output 10 mW power beyond 5 GHz and can also be easily disposed of due to the use of cellulose nanofibril paper as the circuit substrate. The demonstration represents a critical step forward in realizing flexible wireless communication devices.

A pH-responsive silica-metal-organic framework hybrid nanoparticle for the delivery of hydrophilic drugs, nucleic acids, and CRISPR-Cas9 genome-editing machineries.

Efficient delivery of hydrophilic drugs, nucleic acids, proteins, and any combination thereof is essential for various biomedical applications. Herein, we report a straightforward, yet versatile approach to efficiently encapsulate and deliver various hydrophilic payloads using a pH-responsive silica-metal-organic framework hybrid nanoparticle (SMOF NP) consisting of both silica and zeolitic imidazole framework (ZIF). This unique SMOF NP offers a high loading content and efficiency, excellent stability, and robust intracellular delivery of a variety of payloads, including hydrophilic small molecule drugs (e.g., doxorubicin hydrochloride), nucleic acids (e.g., DNA and mRNA), and genome-editing machineries (e.g., Cas9-sgRNA ribonucleoprotein (RNP), and RNP together with donor DNA (e.g., RNP + ssODN)). The superior drug delivery/gene transfection/genome-editing efficiencies of the SMOF NP are attributed to its pH-controlled release and endosomal escape capabilities due to the proton sponge effect enabled by the imidazole moieties in the SMOF NPs. Moreover, the surface of the SMOF NP can be easily customized (e.g., PEGylation and ligand conjugation) via various functional groups incorporated into the silica component. RNP-loaded SMOF NPs induced efficient genome editing in vivo in murine retinal pigment epithelium (RPE) tissue via subretinal injection, providing a highly promising nanoplatform for the delivery of a wide range of hydrophilic payloads.

Phytochrome-interacting factors regulate seedling growth through ABA signaling.

There is a growing body of evidence that abscisic acid (ABA) and the phytochrome-interacting factor (PIF) family of transcription factors interact in light signaling, the regulation of plant growth development, and adaptation to environmental stimuli. In this study, we investigate the role that PIFs play in the regulation of ABA signaling in Arabidopsis thaliana seedlings grown under long-day conditions. We showed that PIFs positively regulate ABA signaling in post-germination seedling growth. We analyzed the DNA-binding sites for PIF3 and PIF5 by DNA-affinity purification sequencing (DAP-seq) genome-wide. The DAP-seq data showed that G-box motif is the direct binding site of PIF3 and PIF5, and a number of ABA responsive genes are potential targets of PIFs, including PYL3, PYL6, PYL12, SnRK2.2, CPK4, CPK6, ABI5, ABF3, and KIN1. Our results provide a basis for understanding the mechanism for PIFs in regulating ABA signal transduction.

Populus euphratica remorin 6.5 activates plasma membrane H+-ATPases to mediate salt tolerance.

Remorins (REMs) play an important role in the ability of plants to adapt to adverse environments. PeREM6.5, a protein of the REM family in Populus euphratica (salt-resistant poplar), was induced by NaCl stress in callus, roots and leaves. We cloned the full-length PeREM6.5 from P. euphratica and transformed it into Escherichia coli and Arabidopsis thaliana. PeREM6.5 recombinant protein significantly increased the H+-ATPase hydrolytic activity and H+ transport activity in P. euphratica plasma membrane (PM) vesicles. Yeast two-hybrid assay showed that P. euphratica REM6.5 interacted with RPM1-interacting protein 4 (PeRIN4). Notably, the PeREM6.5-induced increase in PM H+-ATPase activity was enhanced by PeRIN4 recombinant protein. Overexpression of PeREM6.5 in Arabidopsis significantly improved salt tolerance in transgenic plants in terms of survival rate, root growth, electrolyte leakage and malondialdehyde content. Arabidopsis plants overexpressing PeREM6.5 retained high PM H+-ATPase activity in both in vivo and in vitro assays. PeREM6.5-transgenic plants had reduced accumulation of Na+ due to the Na+ extrusion promoted by the H+-ATPases. Moreover, the H+ pumps caused hyperpolarization of the PM, which reduced the K+ loss mediated by the depolarization-activated channels in the PM of salinized roots. Therefore, we conclude that PeREM6.5 regulated H+-ATPase activity in the PM, thus enhancing the plant capacity to maintain ionic homeostasis under salinity.

A unique temporary collateral pathway between carotid-vertebrobasilar arteries in a carotid dissection patient.

BACKGROUND: In adults, the anastomosis between carotid and vertebrobasilar arteries is usually the posterior communicating artery, sometimes the primitive trigeminal artery. In this case, the basilar artery fed the internal carotid artery through the pontine-to-tentorial artery anastomosis after severe stenosis from traumatic carotid dissection. CASE PRESENTATION: A 32-year-old female was diagnosed with ischemic stroke caused by traumatic carotid artery dissection. Aspirin (100 mg/day) and clopidogrel (75 mg/day) were prescribed. Digital subtraction angiography performed 6 days after stroke onset showed a dissection in the cervical segment of left internal carotid artery with severe local stenosis, and a collateral pathway from BA to the cavernous segment of internal carotid artery through the lateral pontine and tentorial artery. Without interventional therapy, clinical symptoms improved significantly within 10 days after onset. At 3-month follow-up, left common carotid artery angiography showed the stenosis had been significantly improved with a residual aneurysm. There was no collateral pathway between carotid-vertebrobasilar arteries, and a residual small artery originated from the posterior vertical segment of cavernous internal carotid artery. The small artery was clearly visualized by 3-dimensional rotational angiography and identified the tentorial artery. CONCLUSION: To the author's knowledge, this is the first report of a collateral pathway between carotid vertebrobasilar arteries through the pontine-to-tentorial artery anastomosis. Meanwhile, tentorial artery origination directly from the cavernous segment of internal carotid artery is rare and easily mistaken for persistent primitive trigeminal artery. 3-dimensional rotational angiography can provide sensitive and accurate diagnostic assessment of the small artery, and may be a useful tool for screening of abnormal small arteries.