Transcription factor ZmEREB97 regulates nitrate uptake in maize (Zea mays) roots.

Maize (Zea mays L.) has very strong requirements for nitrogen. However, the molecular mechanisms underlying the regulations of nitrogen uptake and translocation in this species are not fully understood. Here, we report that an APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor ZmEREB97 functions as an important regulator in the N-signaling network in maize. Predominantly expressed and accumulated in main root and lateral root primordia, ZmEREB97 rapidly responded to nitrate treatment. By overlapping the analyses of differentially expressed genes and conducting a DAP-seq assay, we identified 1446 potential target genes of ZmEREB97. Among these, 764 genes were co-regulated in two lines of zmereb97 mutants. Loss of function of ZmEREB97 substantially weakened plant growth under both hydroponic and soil conditions. Physiological characterization of zmereb97 mutant plants demonstrated that reduced biomass and grain yield were both associated with reduced nitrate influx, decreased nitrate content and less N accumulation. We further demonstrated that ZmEREB97 directly targets and regulates the expression of six ZmNRT genes by binding to the GCC box-related sequences in gene promoters. Collectively, these data suggest that ZmEREB97 is a major positive regulator of the nitrate response and that it plays an important role in optimizing nitrate uptake, offering a target for improvement of nitrogen use efficiency in crops.

Gastrodin combined with electroacupuncture prevents the development of cerebral ischemia via rebalance of brain-derived neurotrophic factor and interleukin-6 in stroke model rats.

Traditional Chinese medicine (TCM) has long been used to treat various diseases, including cerebral ischemia. The specific molecular mechanism of TCM in the treatment of cerebral ischemia, however, is still unclear. This study investigated the effects of gastrodin, electroacupuncture and their combination on cerebral ischemic rats. We used Nissl staining, immunohistochemical staining and immunoblotting to detect the expression changes of brain-derived neurotrophic factor (BDNF) and interleukin-6 (IL-6) in the frontal cortex. The results showed that the combination therapy of gastrodin and electroacupuncture significantly increased the number of Nissl-positive neurons and improved cell morphology compared with other groups. Mechanistically, we found that the combination of gastrodin and electroacupuncture treatment group can restore the abnormal morphology of neuronal cells caused by cerebral ischemia by rebalancing the expression levels of BDNF and IL-6. Our research indicates that gastrodin combined with electroacupuncture has a significant protective effect on cerebral ischemic injury in rats, possibly by regulating the expression of BDNF and IL-6. This combination therapy is superior to single-drug or electroacupuncture therapy.

VrMYB90 Functions Synergistically with VrbHLHA and VrMYB3 to Regulate Anthocyanin Biosynthesis in Mung Bean.

Mung bean is an important grain-legume crop and its sprout is an economical and nutrient vegetable for the public, but the genetic regulation of anthocyanin production, which is an antioxidant in mung bean, remains elusive. In our study, we characterized a subgroup (SG) 6 R2R3-MYB anthocyanin activator VrMYB90 and a SG 4 R2R3-MYB anthocyanin repressor VrMYB3, which synergistically function in regulating anthocyanin synthesis with VrbHLHA transcription factor. The overexpressed VrMYB90 protein activates the expression of VrMYB3 and VrbHLHA in mung bean hair roots, and also promotes VrDFR and VrANS transcript levels by directly binding to the corresponding promoters at specific motifs (CAACTG and CCGTTG). VrMYB90 interacts with VrbHLHA to enhance its regulatory activities on VrDFR and VrANS. Furthermore, the interaction between VrMYB3 with VrMYB90 and VrbHLHA could result in the restriction of anthocyanin synthesis to prevent excessive anthocyanin accumulation. Our results demonstrate that the VrMYB90 protein, in conjunction with VrMYB3 and VrbHLHA, forms a key regulatory module to fine-tune anthocyanin synthesis in mung bean.

Indocyanine Green Reduces the Viability of Human Lens Epithelial Cells and Promotes Cytolysis: An Ex Vivo Study.

Purpose: To investigate the effects of indocyanine green (ICG) solution on the viability and cytolysis of human lens epithelial cells ex vivo. Methods: A total of 200 pieces of anterior capsules were obtained during cataract surgery, and 110 pieces of the anterior capsules were randomly divided into five groups and treated by immersion in different concentrations of ICG solution. The remaining 90 anterior capsules were also divided into five groups and treated with a combination of drug immersion and washing in balanced salt solution. Electron microscopy and trypan blue and eosin stains were used to analyze the cells. Percentage of dead, shedding, or living lens epithelial cells was estimated and used to demonstrate effects of the ICG on viability and cytolysis. Results: Compared with the control group, the percentage of dead and shedding lens epithelial cells increased while the percentage of living lens epithelial cells decreased in all the immersion groups. In the washing groups, the percentage of the living lens epithelial cells was 63.42% ± 2.49%, 54.04% ± 1.84%, 43.51% ± 2.63%, 29.21% ± 2.40%, and 15.73% ± 1.61% for the five groups and reflected a concentration-effect relationship. Electron microscopy showed that the higher the concentration of the ICG solution, the more severe the destruction of the lens epithelial cell structure. Conclusions: ICG could reduce the viability of the lens epithelial cells and promote cell cytolysis. Translational Relevance: Our study showed that ICG could directly reduce the viability of the lens epithelial cells in a concentration-dependent fashion, which can theoretically reduce the incidence of posterior capsule opacification.

A combinatorial variation in surface chemistry and pore size of three-dimensional porous poly(ε-caprolactone) scaffolds modulates the behaviors of mesenchymal stem cells.

Biomaterial properties play significant roles in controlling cellular behaviors. The objective of the present study was to investigate how pore size and surface chemistry of three-dimensional (3D) porous scaffolds regulate the fate of mesenchymal stem cells (MSCs) in vitro in combination. First, on poly(ε-caprolactone) (PCL) films, the hydrolytic treatment was found to stimulate the adhesion, spreading and proliferation of human MSCs (hMSCs) in comparison with pristine films, while the aminolysis showed mixed effects. Then, 3D porous PCL scaffolds with varying pore sizes (100-200µm, 200-300µm and 300-450µm) were fabricated and subjected to either hydrolysis or aminolysis. It was found that a pore size of 200-300µm with hydrolysis in 3D scaffolds was the most favorable condition for growth of hMSCs. Importantly, while a pore size of 200-300µm with hydrolysis for 1h supported the best osteogenic differentiation of hMSCs, the chondrogenic differentiation was greatest in scaffolds with a pore size of 300-450µm and treated with aminolysis for 1h. Taken together, these results suggest that surface chemistry and pore size of 3D porous scaffolds may potentially have a synergistic impact on the behaviors of MSCs.