LUX ARRHYTHMO links CBF pathway and jasmonic acid metabolism to regulate cold tolerance of tea plants.

Cold stress declines the quality and yield of tea, yet the molecular basis underlying cold tolerance of tea plants (Camellia sinensis) remains largely unknown. Here, we identified a circadian rhythm component LUX ARRHYTHMO (LUX) that potentially regulates cold tolerance of tea plants through a genome-wide association study and transcriptomic analysis. The expression of CsLUX phased with sunrise and sunset and was strongly induced by cold stress. Genetic assays indicated that CsLUX is a positive regulator of freezing tolerance in tea plants. CsLUX was directly activated by CsCBF1 and repressed the expression level of CsLOX2, which regulates the cold tolerance of tea plants through dynamically modulating jasmonic acid content. Furthermore, we showed that the CsLUX-CsJAZ1 complex attenuated the physical interaction of CsJAZ1 with CsICE1, liberating CsICE1 with transcriptional activities to withstand cold stress. Notably, a single-nucleotide variation of C-to-A in the coding region of CsLUX was functionally validated as the potential elite haplotype for cold response, which provided valuable molecular markers for future cold resistance breeding in tea plants.

Glufosinate-ammonium causes liver injury in zebrafish by blocking the Nrf2 pathway.

Glufosinate-ammonium (GLA) is a widely used herbicide, but less research has been done on its harmful effects on non-target organisms, especially aquatic organisms. In this study, 600 adult zebrafish were exposed to different concentration of GLA (0, 1.25, 2.5, 5, 10, and 20 mg/L) for 7 days, and the livers were dissected on the eighth day to examine the changes in liver structure, function, oxidative stress, inflammation, apoptosis, and Nrf2 pathway, and finally to clarify the mechanism of GLA induced liver injury in zebrafish. The levels of alanine aminotransferase, aspartate aminotransferase, reactive oxygen species, malondialdehyde, inflammatory factors (IL-6 and TNF-α), and caspase-3 gradually increased, while the levels of superoxide dismutase, catalase, glutathione, and glutathione peroxidase gradually decreased with the increase of GLA concentration. The Nrf2 pathway was activated at low concentrations (1.25-5 mg/L) and significantly inhibited at high concentrations (10 and 20 mg/L). These results suggested that GLA could cause oxidative stress, inflammation, and apoptosis in zebrafish liver. Therefore, GLA can cause liver injury in zebrafish, and at high concentrations, the inhibition of Nrf2 pathway is one of the important causes of liver injury.

Human Motion Enhancement and Restoration via Unconstrained Human Structure Learning.

Human motion capture technology, which leverages sensors to track the movement trajectories of key skeleton points, has been progressively transitioning from industrial applications to broader civilian applications in recent years. It finds extensive use in fields such as game development, digital human modeling, and sport science. However, the affordability of these sensors often compromises the accuracy of motion data. Low-cost motion capture methods often lead to errors in the captured motion data. We introduce a novel approach for human motion reconstruction and enhancement using spatio-temporal attention-based graph convolutional networks (ST-ATGCNs), which efficiently learn the human skeleton structure and the motion logic without requiring prior human kinematic knowledge. This method enables unsupervised motion data restoration and significantly reduces the costs associated with obtaining precise motion capture data. Our experiments, conducted on two extensive motion datasets and with real motion capture sensors such as the SONY (Tokyo, Japan) mocopi, demonstrate the method's effectiveness in enhancing the quality of low-precision motion capture data. The experiments indicate the ST-ATGCN's potential to improve both the accessibility and accuracy of motion capture technology.

Detecting Leadership Opportunities in Group Discussions Using Off-the-Shelf VR Headsets.

The absence of some forms of non-verbal communication in virtual reality (VR) can make VR-based group discussions difficult even when a leader is assigned to each group to facilitate discussions. In this paper, we discuss if the sensor data from off-the-shelf VR devices can be used to detect opportunities for facilitating engaging discussions and support leaders in VR-based group discussions. To this end, we focus on the detection of suppressed speaking intention in VR-based group discussions by using personalized and general models. Our extensive analysis of experimental data reveals some factors that should be considered to enable effective feedback to leaders. In particular, our results show the benefits of combining the sensor data from leaders and low-engagement participants, and the usefulness of specific HMD sensor features.

Theanine transporters identified in tea plants (Camellia sinensis L.).

Theanine, a unique non-proteinogenic amino acid, is an important component of tea, as it confers the umami taste and relaxation effect of tea as a beverage. Theanine is primarily synthesized in tea roots and is subsequently transported to young shoots, which are harvested for tea production. Currently, the mechanism for theanine transport in the tea plant remains unknown. Here, by screening a yeast mutant library, followed by functional analyses, we identified the glutamine permease, GNP1 as a specific transporter for theanine in yeast. Although there is no GNP1 homolog in the tea plant, we assessed the theanine transport ability of nine tea plant amino acid permease (AAP) family members, with six exhibiting transport activity. We further determined that CsAAP1, CsAAP2, CsAAP4, CsAAP5, CsAAP6, and CsAAP8 exhibited moderate theanine affinities and transport was H+ -dependent. The tissue-specific expression of these six CsAAPs in leaves, vascular tissues, and the root suggested their broad roles in theanine loading and unloading from the vascular system, and in targeting to sink tissues. Furthermore, expression of these CsAAPs was shown to be seasonally regulated, coincident with theanine transport within the tea plant. Finally, CsAAP1 expression in the root was highly correlated with root-to-bud transport of theanine, in seven tea plant cultivars. Taken together, these findings support the hypothesis that members of the CsAAP family transport theanine and participate in its root-to-shoot delivery in the tea plant.

HAK/KUP/KT family potassium transporter genes are involved in potassium deficiency and stress responses in tea plants (Camellia sinensis L.): expression and functional analysis.

BACKGROUND: Tea plant is one of the most important non-alcoholic beverage crops worldwide. While potassium (K+) is an essential macronutrient and greatly affects the growth and development of plants, the molecular mechanism underlying K+ uptake and transport in tea plant root, especially under limited-K+ conditions, is still poorly understood. In plants, HAK/KUP/KT family members play a crucial role in K+ acquisition and translocation, growth and development, and response to stresses. Nevertheless, the biological functions of these genes in tea plant are still in mystery, especially their roles in K+ uptake and stress responses. RESULTS: In this study, a total of 21 non-redundant HAK/KUP/KT genes (designated as CsHAKs) were identified in tea plant. Phylogenetic and structural analysis classified the CsHAKs into four clusters (I, II, III, IV), containing 4, 8, 4 and 5 genes, respectively. Three major categories of cis-acting elements were found in the promoter regions of CsHAKs. Tissue-specific expression analysis indicated extremely low expression levels in various tissues of cluster I CsHAKs with the exception of a high root expression of CsHAK4 and CsHAK5, a constitutive expression of clusters II and III CsHAKs, and a moderate cluster IV CsHAKs expression. Remarkably, the transcript levels of CsHAKs in roots were significantly induced or suppressed after exposure to K+ deficiency, salt and drought stresses, and phytohormones treatments. Also notably, CsHAK7 was highly expressed in all tissues and was further induced under various stress conditions. Therefore, functional characterization of CsHAK7 was performed, and the results demostrated that CsHAK7 locates on plasma membrane and plays a key role in K+ transport in yeast. Taken together, the results provide promising candidate CsHAKs for further functional studies and contribute to the molecular breeding for new tea plants varieties with highly efficient utilization of K+. CONCLUSION: This study demonstrated the first genome-wide analysis of CsHAK family genes of tea plant and provides a foundation for understanding the classification and functions of the CsHAKs in tea plants.

LncWNT3-IT affects the proliferation of Sertoli cells by regulating the expression of the WNT3 gene in goat testis.

The proliferation and differentiation ability of testicular Sertoli cells directly affects spermatogenesis and male reproductive development. WNT proteins are involved in the regulation of cell proliferation, differentiation and spermatogenesis. Therefore, to study whether lncRNAs, which regulate the expression of WNT proteins during cell proliferation and differentiation, are worthwhile. In this study, testicular tissue from the Dazu black goat (Capra, goat, Chongqing, China) at neonatal time (less than 7 days old), early puberty time (45 days old) and sexual maturity time (90 days old) at three ages was subjected to high-throughput sequencing to predict testicular growth and development associated with WNT lncRNA. The final screening of lncWNT3-IT may be targeted to regulate the expression of WNT3. At the same time, the expression of WNT3 was verified by lncWNT3-IT by paraffin sectioning, fluorescence in situ hybridization, interference, overexpression, cytotoxicity assay, Western blotting and qPCR. The following results were obtained: lncWNT3-IT was expressed in the testicular Sertoli cells and played a role in the Sertoli cell cytoplasm. Fluorescence in situ hybridization localization analysis showed that lncWNT3-IT positively regulated the expression of WNT3, and through cell viability and cell proliferation experiments, it was found that the expression of lncWNT3-IT assisted in Sertoli cell proliferation. In summary, lncWNT3-IT can influence the proliferation of Sertoli cells by positively regulating the expression of WNT3.

Toxic effects of hydrogen sulfide donor NaHS induced liver apoptosis is regulated by complex IV subunits and reactive oxygen species generation in rats.

In recent years, the protective effect of hydrogensulfide donor sodium hydrosulfide(NaHS) on multiple organs has been widely reported. The study aimed to explorethe effect of commonly used concentration of NaHS on theliver and its potential damage mechanism. Rats divided into 4 groups: control, NaHS I (1 mg/kg), II (3 mg/kg) and III(5 mg/kg) groups, and each group is divided into four-timepoints (2, 6, 12, and 24 hours). Results showed that H2S concentration increased, mitochondrial complex IV activity inhibited, the COX I and IV subunits and mitochondrial apoptosis pathway-related proteins expression increased in atime- and dose-dependent manner. We confirmed that 1 mg/kg NaHS had no injuryeffect on the liver, 3 and 5 mg/kg NaHS inhibitsthe activity of mitochondrial complex IV by promoting COX I and IV subunits expression, leading to the increase in ROS and ultimately inducing apoptosis and liver injury.

Dexmedetomidine ameliorates lipopolysaccharide-induced acute kidney injury in rats by inhibiting inflammation and oxidative stress via the GSK-3ß/Nrf2 signaling pathway.

Acute kidney injury (AKI) is a frequent and serious complication of sepsis; however, there are currently no effective therapies. Inflammation and oxidative stress are the major mechanisms implicated in lipopolysaccharide (LPS)-induced AKI. Dexmedetomidine (DEX) has been reported to have remarkable anti-inflammatory and antioxidant effects. Here, we examined the renoprotective effects of DEX and potential underlying mechanisms in rats with LPS-induced AKI. We analyzed renal function and structure; serum inflammatory cytokine; renal oxidant and antioxidant levels; and renal expression of glycogen synthase kinase-3ß (GSK-3ß)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway-related proteins in rats 4 hr after administration of LPS. Pretreatment with DEX improved renal function and significantly reduced the levels of inflammatory cytokines and oxidative stress markers. Treatment with DEX and the GSK-3ß inhibitor SB216367 promoted phosphorylation of GSK-3ß, induced Nrf2 nuclear translocation, and increased transcription of the Nrf2 target genes heme oxygenase-1 and NAD(P)H quinone oxidoreductase-1, primarily in renal tubules. Alpha-2-adrenergic receptor (α2-AR) antagonist atipamezole and imidazoline I 2 receptor (I 2 R) antagonist idazoxan reversed the effects of DEX. These results suggest that the renoprotective effects of DEX are mediated via α2-AR and I 2 R-dependent pathways that reduce inflammation and oxidative stress through GSK-3ß/Nrf2 signaling.

Significantly increased amino acid accumulation in a novel albino branch of the tea plant (Camellia sinensis).

MAIN CONCLUSION: A normal tea plant with one albino branch was discovered. RNA sequencing, albinism phenotype and ultrastructural observations provided a valuable understanding of the albino mechanism in tea plants. Tea plants with a specific color (white or yellow) have been studied extensively. A normal tea plant (Camellia sinensis cv. quntizhong) with one albino branch was discovered in a local tea plantation in Huangshan, Anhui, China. The pure albino leaves on this special branch had accumulated a fairly high content of amino acids, especially theanine (45.31 mg/g DW), and had a low concentration of polyphenols and an extremely low chlorophyll (Chl) content compared with control leaves. Ultrastructural observation of an albino leaf revealed no chloroplasts, whereas it was viable in the control leaf. RNA sequencing and differentially expressed gene (DEG) analysis were performed on the albino leaves and on control leaves from a normal green branch. The related genes involved in theanine and polyphenol biosynthesis were also investigated in this study. DEG expression patterns in Chl biosynthesis or degradation, carotenoid biosynthesis or degradation, chloroplast development, and biosynthesis were influenced in the albino leaves. Chloroplast deletion in albino leaves had probably destroyed the balance of carbon and nitrogen metabolism, leading to a high accumulation of free amino acids and a low concentration of polyphenols in the albino leaves. The obtained results can provide insight into the mechanism underlying this special albino branch phenotype, and are a valuable contribution toward understanding the albino mechanism in tea plants.

Integrated analysis of miRNAs and their targets reveals that miR319c/TCP2 regulates apical bud burst in tea plant (Camellia sinensis).

MAIN CONCLUSION: The roles of microRNA-mediated epigenetic regulation were highlighted in the bud dormancy-activity cycle, implying that certain differentially expressed miRNAs play crucial roles in apical bud burst, such as csn-miR319c/TCP2. microRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression by targeting mRNA transcripts for cleavage or directing translational inhibition. To investigate whether miRNAs regulate bud dormancy-activation transition in tea plant, which largely affects the yield and price of tea products and adaptability of tea trees, we constructed small RNA libraries from three different periods of bud dormancy-burst transition. Through sequencing analysis, 262 conserved and 83 novel miRNAs were identified, including 118 differentially expressed miRNAs. Quantitative RT-PCR results for randomly selected miRNAs exhibited that our comprehensive analysis is highly reliable and accurate. The content of caffeine increased continuously from the endodormancy bud to flushing bud, and differentially expressed miRNAs coupling with their targets associated with bud burst were identified. Remarkably, csn-miR319c was downregulated significantly from the quiescent bud to burst bud, while its target gene CsnTCP2 (TEOSINTE BRANCHED/CYCLOIDEA/PROLIFERATING CELL FACTOR 2) displayed opposite expression patterns. Co-transformation experiment in tobacco demonstrated that csn-miR319c can significantly suppress the functions of CsnTCP2. This study on miRNAs and the recognition of target genes could provide new insights into the molecular mechanism of the bud dormancy-activation transition in tea plant.

A WRKY transcription factor PbrWRKY53 from Pyrus betulaefolia is involved in drought tolerance and AsA accumulation.

WRKY comprises a large family of transcription factors in plants, but most WRKY members are still poorly understood. In this study, we report the identification and functional characterization of PbrWRKY53 isolated from Pyrus betulaefolia. PbrWRKY53 was greatly up-regulated by drought and abscisic acid, but slightly induced by salt and cold. Subcellar localization analyses showed that PbrWRKY53 was located in the nucleus. Ectopic expression of PbrWRKY53 in tobacco and Pyrus ussuriensis conferred enhanced tolerance to drought stress. The transgenic plants exhibited better water status, less reactive oxygen species generation and higher levels of antioxidant enzyme activities and metabolites than the wild type. In addition, overexpression of PbrWRKY53 in transgenic tobacco resulted in enhanced expression level of PbrNCED1, and led to the increase in larger amount of vitamin C accumulation in comparison to WT. Knock-down of PbrWRKY53 in P. ussuriensis down-regulated PbrNCED1 abundance, accompanied by compromised drought tolerance. Yeast one-hybrid assay, EMSA and transient expression analysis demonstrated that PbrWRKY53 could bind to the W-box element in the promoter region of PbrNCED1. Taken together, these results demonstrated that PbrWRKY53 plays a positive role in drought tolerance, which might be, at least in part, promoting production of vitamin C via regulating PbrNCED1 expression.

Differential gene expression and transport functionality in the bundle sheath versus mesophyll - a potential role in leaf mineral homeostasis.

Under fluctuating ambient conditions, the ability of plants to maintain hydromineral homeostasis requires the tight control of long distance transport. This includes the control of radial transport within leaves, from veins to mesophyll. The bundle sheath is a structure that tightly wraps around leaf vasculature. It has been suggested to act as a selective barrier in the context of radial transport. This suggestion is based on recent physiological transport assays of bundle sheath cells (BSCs), as well as the anatomy of these cells.We hypothesized that the unique transport functionality of BSCs is apparent in their transcriptome. To test this, we compared the transcriptomes of individually hand-picked protoplasts of GFP-labeled BSCs and non-labeled mesophyll cells (MCs) from the leaves of Arabidopsis thaliana. Of the 90 genes differentially expressed between BSCs and MCs, 45% are membrane related and 20% transport related, a prominent example being the proton pump AHA2. Electrophysiological assays showed that the major AKT2-like membrane K+ conductances of BSCs and MCs had different voltage dependency ranges. Taken together, these differences may cause simultaneous but oppositely directed transmembrane K+ fluxes in BSCs and MCs, in otherwise similar conditions.

Anion Channel Inhibitor NPPB-Inhibited Fluoride Accumulation in Tea Plant (Camellia sinensis) Is Related to the Regulation of Ca²âº, CaM and Depolarization of Plasma Membrane Potential.

Tea plant is known to be a hyper-accumulator of fluoride (F). Over-intake of F has been shown to have adverse effects on human health, e.g., dental fluorosis. Thus, understanding the mechanisms fluoride accumulation and developing potential approaches to decrease F uptake in tea plants might be beneficial for human health. In the present study, we found that pretreatment with the anion channel inhibitor NPPB reduced F accumulation in tea plants. Simultaneously, we observed that NPPB triggered Ca(2+) efflux from mature zone of tea root and significantly increased relative CaM in tea roots. Besides, pretreatment with the Ca(2+) chelator (EGTA) and CaM antagonists (CPZ and TFP) suppressed NPPB-elevated cytosolic Ca(2+) fluorescence intensity and CaM concentration in tea roots, respectively. Interestingly, NPPB-inhibited F accumulation was found to be significantly alleviated in tea plants pretreated with either Ca(2+) chelator (EGTA) or CaM antagonists (CPZ and TFP). In addition, NPPB significantly depolarized membrane potential transiently and we argue that the net Ca(2+) and H⁺ efflux across the plasma membrane contributed to the restoration of membrane potential. Overall, our results suggest that regulation of Ca(2+)-CaM and plasma membrane potential depolarization are involved in NPPB-inhibited F accumulation in tea plants.

Al(3+) -promoted fluoride accumulation in tea plants (Camellia sinensis) was inhibited by an anion channel inhibitor DIDS.

BACKGROUND: Generally, tea plants are grown in acid soil which is rich in aluminum (Al) and fluoride (F). A recent publication showed that pretreatment with Al(3+) promoted F accumulation in tea plants by increasing endogenous Ca(2+) and calmodulin (CaM). A high level of F in tea leaves not only impairs tea quality but also might pose a health risk for people drinking tea regularly. Therefore it is important to try to find some clues which might be beneficial in controlling F accumulation in tea plants grown in acid soil (Al(3+) ). RESULTS: It was found that diisothiocyanostilbene-2,2-disulfonic acid (DIDS) significantly reduced Al(3+) -promoted F accumulation in tea plants. Additionally, Al(3+) plus DIDS treatment stimulated significantly higher Ca(2+) efflux and decreased the CaM level in tea roots compared with Al(3+) treatment. Besides, significantly higher depolarization of membrane potential was shown in tea roots treated with Al(3+) plus DIDS than in those treated with Al(3+) , as well as higher net total H(+) efflux and plasma membrane H(+) -ATPase activity. CONCLUSION: Al(3+) -promoted F accumulation in tea plants was inhibited by an anion channel inhibitor DIDS. Ca(2+) /CaM and membrane potential depolarization may be the components involved in this process. © 2016 Society of Chemical Industry.

The role of a potassium transporter OsHAK5 in potassium acquisition and transport from roots to shoots in rice at low potassium supply levels.

In plants, K transporter (KT)/high affinity K transporter (HAK)/K uptake permease (KUP) is the largest potassium (K) transporter family; however, few of the members have had their physiological functions characterized in planta. Here, we studied OsHAK5 of the KT/HAK/KUP family in rice (Oryza sativa). We determined its cellular and tissue localization and analyzed its functions in rice using both OsHAK5 knockout mutants and overexpression lines in three genetic backgrounds. A ß-glucuronidase reporter driven by the OsHAK5 native promoter indicated OsHAK5 expression in various tissue organs from root to seed, abundantly in root epidermis and stele, the vascular tissues, and mesophyll cells. Net K influx rate in roots and K transport from roots to aerial parts were severely impaired by OsHAK5 knockout but increased by OsHAK5 overexpression in 0.1 and 0.3 mm K external solution. The contribution of OsHAK5 to K mobilization within the rice plant was confirmed further by the change of K concentration in the xylem sap and K distribution in the transgenic lines when K was removed completely from the external solution. Overexpression of OsHAK5 increased the K-sodium concentration ratio in the shoots and salt stress tolerance (shoot growth), while knockout of OsHAK5 decreased the K-sodium concentration ratio in the shoots, resulting in sensitivity to salt stress. Taken together, these results demonstrate that OsHAK5 plays a major role in K acquisition by roots faced with low external K and in K upward transport from roots to shoots in K-deficient rice plants.

Rice potassium transporter OsHAK1 is essential for maintaining potassium-mediated growth and functions in salt tolerance over low and high potassium concentration ranges.

Potassium (K) absorption and translocation in plants rely upon multiple K transporters for adapting varied K supply and saline conditions. Here, we report the expression patterns and physiological roles of OsHAK1, a member belonging to the KT/KUP/HAK gene family in rice (Oryza sativa L.). The expression of OsHAK1 is up-regulated by K deficiency or salt stress in various tissues, particularly in the root and shoot apical meristem, the epidermises and steles of root, and vascular bundles of shoot. Both oshak1 knockout mutants in comparison to their respective Dongjin or Manan wild types showed a dramatic reduction in K concentration and stunted root and shoot growth. Knockout of OsHAK1 reduced the K absorption rate of unit root surface area by ∼50-55 and ∼30%, and total K uptake by ∼80 and ∼65% at 0.05-0.1 and 1 mm K supply level, respectively. The root net high-affinity K uptake of oshak1 mutants was sensitive to salt stress but not to ammonium supply. Overexpression of OsHAK1 in rice increased K uptake and K/Na ratio. The positive relationship between K concentration and shoot biomass in the mutants suggests that OsHAK1 plays an essential role in K-mediated rice growth and salt tolerance over low and high K concentration ranges.

Dexmedetomidine Alleviates Acute Stress-Induced Acute Kidney Injury by Attenuating Inflammation and Oxidative Stress via Inhibiting the P2X7R/NF-κB/NLRP3 Pathway in Rats.

This study aimed to investigate the potential protective effects of Dexmedetomidine (DEX) against acute kidney injury (AKI) induced by acute stress (AS). Wistar rats were divided into five groups: Control, DEX, AS, AS + DEX, and AS + A438079. The results showed that AS led to AKI by increasing inflammatory biomarkers and oxidative stress-related indicators. The acute stress model in rats was successfully established. Renal function, histopathology, oxidative stress, and inflammation were assessed. Localization of P2X7 receptor (P2X7R) was determined by immunofluorescence. Additionally, the key inflammatory proteins of the P2X7R/NF-κB/NLRP3 signaling pathway were measured by Western blotting. DEX significantly improved kidney function, alleviated kidney injury, and reduced oxidative stress and inflammation. DEX inhibited the activation of the P2X7R, decreased the expression of NF-κB, NLRP3 inflammasome, and Caspase-1, and inhibited the expression of interleukin-1ß (IL-1ß) and tumor necrosis factor α (TNFα). Furthermore, DEX also alleviated AS-induced AKI by inhibiting the excessive production of reactive oxygen species (ROS) and reducing oxidative stress. In conclusion, DEX attenuates AS-induced AKI by mitigating inflammation and oxidative stress through the inhibition of the P2X7R/NF-κB/NLRP3 pathway in rats.