Silicon (Si) can alleviate salt stress by decreasing Na+ bypass flow in rice (Oryza sativa L.), however, the mechanisms underpinning remain veiled. In this study, we investigated the roles of OsLsi1 and OsLsi2 in Si-induced reduction of bypass flow and its resultant alleviation of salt stress by using lsi1 and lsi2 mutants (defective in OsLsi1 and OsLsi2, respectively) and their wild types (WTs). Under salt stress, Si promoted plant growth and decreased root-to-shoot Na+ translocation in WTs, but not in mutants. Simultaneously, quantitative estimation and fluorescent visualization of trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic (PTS, an apoplastic tracer) showed Si reduced bypass flow in WTs, but not in mutants. Energy-dispersive X-ray microanalysis (EDX) showed Si was deposited at root endodermis in WTs, but not in mutants. Moreover, results obtained from root split experiment using lsi1 WT showed down-regulated expression of Si transport genes (OsLsi1 and OsLsi2) in root accelerated Si deposition at root endodermis. In summary, our results reveal that Si deposition at root endodermis and its resultant reduction of Na+ bypass flow is modulated by OsLsi1 and OsLsi2 and regulated by the expression of OsLsi1 and OsLsi2, implying that root Si deposition could be an active and physiologically-regulated process in rice.Cinnamomum camphora (L.) Presl, rich in terpenoids, is an important commercial plant. https://www.selleckchem.com/products/CP-690550.html The monoterpenes borneol and camphor are highly desired compounds that have been widely and diversely used in medicine and spices since ancient times. However, the key enzymes in the biosynthetic pathway of borneol and camphor in C. camphora remains unknown, which limits access to these natural products. Here, the chirality of borneol and camphor were identified in C. camphora leaves. Besides the main (+)-borneol and (+)-camphor, C. camphora also contains small amounts of (-)-borneol and (-)-camphor. Then, CcBDH3 - an efficient (+)-borneol dehydrogenase (BDH) - was identified that catalyzed (+)-borneol into (+)-camphor in the presence of NAD+. The Km value was 25.1 μM with a kcat value of 5.4 × 10-3 s-1 at pH 8.5 and 30 °C. CcBDH3, which also yields (-)-camphor from (-)-borneol as a substrate, had a Km value of 36.9 μM with a kcat of 2.1 × 10-3 s-1, and pH of 8.0 and temperature of 32 °C. We further compared the conformational specificity of two other reported BDHs, ZSD1 and ADH2, and found that ZSD1 had the highest conversion rate with (-)-borneol. These findings provide a new way for the production of camphor with various optical activities by metabolic engineering, and the identified camphor biosynthesis pathway provides the foundation for using genetic engineering to improve the production and purity of (+)-borneol in planta.The limited availability of nutrient Fe severely impairs the health of almost all organisms. Endophytic actinobacteria can benefit the host plant in different ways. We previously inferred that the rice (Oryza) endophytic Streptomyces hygroscopicus OsiSh-2 possesses a highly efficient Fe-acquisition system. In this work, we first evaluated the effects of OsiSh-2 on the Fe-deficiency resilience of the host rice. The results demonstrated that the inoculation of OsiSh-2 considerably increased the plant biomass, Fe concentration and translocation factor, and chlorophyll content, and net leaf photosynthetic rate under Fe limiting condition. The expression of genes involved with Fe3+-reduction-related strategy in rice was up-regulated, while that involved with Fe3+-chelation-related strategy was down-regulated by OsiSh-2 treatment. Meanwhile, the OsiSh-2-rice symbiont showed enhancement of Fe3+-chelate reductase activity, total siderophore production, and acidification trend in the rhizosphere under Fe deficiency compared to plants without this endophyte. In conclusion, endophytic OsiSh-2 could protect plants against Fe-deficient stress by a sophisticated interaction with the host, including modulating Fe chelation, solubilization, reduction and translocation, ultimately leading to enhanced fitness of plant.Nitrate transporters (NRTs) participate in nitrate uptake, transport and allocation within the plant. However, this gene family has not been studied thoroughly in spinach. This study provided the general information about spinach SoNRTs and their transcriptional and functional responses to different levels of nitrate supplies. Resultes showed that fifty-seven NPF (also known as NRT1), nine NRT2 and one NRT3 were identified in spinach homologous to characterized Arabidopsis NRT genes. Phylogenetic analysis organized the SoNRT family into three clades NPF with three subclades, NRT2, and NRT3. The tested SoNRT genes showed the various expression profiles in relation to tissue specificity and nitrate supply, indicating their functional diversity in response to external nitrate supply. Among them, transgenic Arabidopsis plants overexpressing SoNPF30 showed improved biomass, decreased shoot nitrate contents but no significant difference of 15NO3- uptake rates when compared with those of the wild type in response to high N treatment. Under low N treatment, overexpressing of SoNRT3 significantly increased whole plant biomass, root nitrate contents and 15NO3- uptake rates. These demonstrated that SoNPF30 and SoNRT3 confer greater capacity for nitrate translocation or nitrate uptake, and could help to improve the ability of plant nitrogen utilization under those conditions. Our findings provide a valuable basis for future research on this family of genes in spinach.Persian poppy (Papaver bracteatum Lindl.) is a perennial medicinal plant belonging to the Papaveraceae family that is endemic to the mountainous areas in Northern Iran. It is known for high amounts of the valuable benzylisoquinoline alkaloid thebaine. The effects of induced polyploidy as well as the effect of methyl Jasmonate (MeJA) elicitation on the root production of thebaine and on the expression of five alkaloid biosynthesis related genes were studied. The in vitro tetraploidy induction caused a significant increased expression of norcoclaurine synthase (NCS) and salutaridinol (SAT), and a significant decreased expression of berberine bridge enzyme (BBE) in the leaves. In the root tissues, the BBE, NCS, and SAT showed an increased expression in tetraploid plants, while codeinone reductase (COR) showed a decreased expression. A similar alteration pattern was found in mixoploid plants when compared to their diploid counterparts. MeJA at concentrations of 0.1 and 0.5 mM caused a remarkable increase in the thebaine content in the roots of treated plants, where the highest thebaine content was identified in plants elicited with 0.