Molecular protocol to develop β-carotene-biofortified rice events via molecular optimization.

Providing food with nutrition and functionality is crucial for sustaining human life. Rice (Oryza sativa L.) is a representative staple crop with high carbohydrate content but low amounts of essential amino acids, micronutrients, and carotenoids such as provitamin A.

The rice NUCLEAR FACTOR-YA5 and MICRORNA169a module promotes nitrogen utilization during nitrogen deficiency.

Nitrogen (N) is essential for plant growth and development. Therefore, understanding its utilization is essential for improving crop productivity. However, much remains to be learned about plant N sensing and signaling.

DROUGHT-INDUCED BRANCHED-CHAIN AMINO ACID AMINOTRANSFERASE enhances drought tolerance in rice.

Plants accumulate several metabolites in response to drought stress, including branched-chain amino acids (BCAAs). However, the roles of BCAAs in plant drought responses and the underlying molecular mechanisms for BCAA accumulation remain elusive. Here, we demonstrate that rice (Oryza sativa) DROUGHT-INDUCED BRANCHED-CHAIN AMINO ACID AMINOTRANSFERASE (OsDIAT) mediates the accumulation of BCAAs in rice in response to drought stress.

Rice NAC17 transcription factor enhances drought tolerance by modulating lignin accumulation.

Land plants have developed a comprehensive system to cope with the drought stress, and it is operated by intricate signaling networks, including transcriptional regulation. Herein, we identified the function of OsNAC17, a member of NAC (NAM, ATAF, and CUC2) transcription factor family, in drought tolerance. OsNAC17 is localized to the nucleus, and its expression was significantly induced under drought conditions.

Rice module enhances drought tolerance by regulation of flavonoid biosynthesis genes.

Plants have evolved sophisticated defense systems to enhance drought tolerance. These include the microRNA (miRNA) group of small noncoding RNAs that act as post-transcriptional regulators; however, details of the mechanisms by which they confer drought tolerance are not well understood. Here, we show that , a member of - gene family, is mainly expressed in response to drought stress and regulates the transcript levels of () and in rice ().

Transcriptional activation of rice CINNAMOYL-CoA REDUCTASE 10 by OsNAC5, contributes to drought tolerance by modulating lignin accumulation in roots.

Drought is a common abiotic stress for terrestrial plants and often affects crop development and yield. Recent studies have suggested that lignin plays a crucial role in plant drought tolerance; however, the underlying molecular mechanisms are still largely unknown. Here, we report that the rice (Oryza sativa) gene CINNAMOYL-CoA REDUCTASE 10 (OsCCR10) is directly activated by the OsNAC5 transcription factor, which mediates drought tolerance through regulating lignin accumulation.

Overexpression of , a Vascular Tissue-Specific Transcription Factor Gene, Confers Drought Tolerance in Rice.

Abiotic stresses severely affect plant growth and productivity. To cope with abiotic stresses, plants have evolved tolerance mechanisms that are tightly regulated by reprogramming transcription factors (TFs). APETALA2/ethylene-responsive factor (AP2/ERF) transcription factors are known to play an important role in various abiotic stresses.

Application of Upstream Open Reading Frames (uORFs) Editing for the Development of Stress-Tolerant Crops.

Global population growth and climate change are posing increasing challenges to the production of a stable crop supply using current agricultural practices. The generation of genetically modified (GM) crops has contributed to improving crop stress tolerance and productivity; however, many regulations are still in place that limit their commercialization. Recently, alternative biotechnology-based strategies, such as gene-edited (GE) crops, have been in the spotlight.

The Rice GLYCINE-RICH PROTEIN 3 Confers Drought Tolerance by Regulating mRNA Stability of ROS Scavenging-Related Genes.

Background: Plant glycine-rich proteins are categorized into several classes based on their protein structures. The glycine-rich RNA binding proteins (GRPs) are members of class IV subfamily possessing N-terminus RNA-recognition motifs (RRMs) and proposed to be involved in post-transcriptional regulation of its target transcripts. GRPs are involved in developmental process and cellular stress responses, but the molecular mechanisms underlying these regulations are still elusive.

2A-linked bi-, tri-, and quad-cistrons for the stepwise biosynthesis of β-carotene, zeaxanthin, and ketocarotenoids in rice endosperm.

Foot-and-mouth disease virus (FMDV) 2A constructs have been successfully used for the production of "Golden Rice", a β-carotene producing rice strain. However, to allay public fears and opposition to plants carrying a mammalian pathogenic viral sequence, 2A-like synthetic sequences from virus and Infectious myonecrosis virus were used to coordinate the coexpression of carotenoid biosynthetic genes. Here, up to four carotenogenic genes encoding PSY, CRTI, BCH and BKT were concatenated and produced β-carotene, zeaxanthin, and ketocarotenoids (astaxanthin and adonixanthin) in transgenic rice seeds displaying color variation due to the difference in carotenoid content and composition.

, a Ribonucleoprotein Gene, Regulates Chloroplast mRNA Stability That Confers Drought and Cold Tolerance.

Chloroplast ribonucleoproteins (cpRNPs) are nuclear-encoded and highly abundant proteins that are proposed to function in chloroplast RNA metabolism. However, the molecular mechanisms underlying the regulation of chloroplast RNAs involved in stress tolerance are poorly understood. Here, we demonstrate that (), a rice () cpRNP gene, is essential for stabilization of RNAs from the NAD(P)H dehydrogenase (NDH) complex, which in turn enhances drought and cold stress tolerance.

Efficiency of Recombinant CRISPR/rCas9-Mediated miRNA Gene Editing in Rice.

Drought is one of the major environmental stresses adversely affecting crop productivity worldwide. Precise characterization of genes involved in drought response is necessary to develop new crop varieties with enhanced drought tolerance. Previously, we identified 66 drought-induced miRNAs in rice plants.

Overexpression of , a CCCH-Zinc Finger, Improves Drought Tolerance in Rice by Regulating Stress-Related Genes.

CCCH zinc finger proteins are members of the zinc finger protein family, and are known to participate in the regulation of development and stress responses via the posttranscriptional regulation of messenger RNA in animals and yeast. However, the molecular mechanism of CCCHZF-mediated drought tolerance is not well understood. We analyzed the functions of , a member of the rice CCCHZF family.

Nitrogen molecular sensors and their use for screening mutants involved in nitrogen use efficiency.

Nitrogen (N) is an essential macronutrient that is required for plant growth and development and has a major impact on crop yield and biomass. However, excessive application of N-based fertilizer results in environmental pollution and increases cultivation cost. A significant target of crop biotechnology is to develop crop varieties with improved N use efficiency (NUE), thereby overcoming these issues.

Gibberellin Promotes Bolting and Flowering via the Floral Integrators and under Marginal Vernalization in Radish.

Gibberellic acid (GA) is one of the factors that promotes flowering in radish ( L.), although the mechanism mediating GA activation of flowering has not been determined. To identify this mechanism in radish, we compared the effects of GA treatment on late-flowering (NH-JS1) and early-flowering (NH-JS2) radish lines.

Transgenic Breeding Approaches for Improving Abiotic Stress Tolerance: Recent Progress and Future Perspectives.

The recent rapid climate changes and increasing global population have led to an increased incidence of abiotic stress and decreased crop productivity. Environmental stresses, such as temperature, drought, nutrient deficiency, salinity, and heavy metal stresses, are major challenges for agriculture, and they lead to a significant reduction in crop growth and productivity. Abiotic stress is a very complex phenomenon, involving a variety of physiological and biochemical changes in plant cells.

OsFKBP20-1b interacts with the splicing factor OsSR45 and participates in the environmental stress response at the post-transcriptional level in rice.

Sessile plants have evolved distinct mechanisms to respond and adapt to adverse environmental conditions through diverse mechanisms including RNA processing. While the role of RNA processing in the stress response is well understood for Arabidopsis thaliana, limited information is available for rice (Oryza sativa). Here, we show that OsFKBP20-1b, belonging to the immunophilin family, interacts with the splicing factor OsSR45 in both nuclear speckles and cytoplasmic foci, and plays an essential role in post-transcriptional regulation of abiotic stress response.

An isoform of the plastid RNA polymerase-associated protein FSD3 negatively regulates chloroplast development.

Background: Plastid-encoded RNA polymerase (PEP) plays an essential role in chloroplast development by governing the expression of genes involved in photosynthesis. At least 12 PEP-associated proteins (PAPs), including FSD3/PAP4, regulate PEP activity and chloroplast development by modulating formation of the PEP complex.

Results: In this study, we identified FSD3S, a splicing variant of FSD3; the FSD3 and FSD3S transcripts encode proteins with identical N-termini, but different C-termini.

Jasmonate Zim-Domain Protein 9 Interacts With Slender Rice 1 to Mediate the Antagonistic Interaction Between Jasmonic and Gibberellic Acid Signals in Rice.

The jasmonic acid (JA) and gibberellic acid (GA) signaling pathways interact to coordinate stress responses and developmental processes. This coordination affects plant growth and yield, and is mediated by interactions between the repressors of each pathway, the JASMONATE ZIM-DOMAIN PROTEIN (JAZ) and DELLA proteins. In this study we attempted to identify rice () JAZs that interact with rice DELLAs such as SLENDER RICE 1 (SLR1).

Allantoin accumulation through overexpression of ureide permease1 improves rice growth under limited nitrogen conditions.

In legumes, nitrogen (N) can be stored as ureide allantoin and transported by ureide permease (UPS) from nodules to leaves where it is catabolized to release ammonium and assimilation to amino acids. In non-leguminous plants especially rice, information on its roles in N metabolism is scarce. Here, we show that OsUPS1 is localized in plasma membranes and are highly expressed in vascular tissues of rice.

Stepwise pathway engineering to the biosynthesis of zeaxanthin, astaxanthin and capsanthin in rice endosperm.

Carotenoid pigments are valuable components of the human diet. A notable example is β-carotene, or provitamin A, which is converted into the derivatives astaxanthin and capsanthin, via the common intermediate zeaxanthin. To generate rice varieties producing diverse carotenoids beyond β-carotene, we specifically used a Capsicum β-carotene hydroxylase gene, B (CaBch) and a codon optimized version of the same gene, stB (stBch) to increase zeaxanthin synthesis.

NGS sequencing reveals that many of the genetic variations in transgenic rice plants match the variations found in natural rice population.

Background: As the transformation process can induce mutations in host plants, molecular characterization of the associated genomic changes is important not only for practical food safety but also for understanding the fundamental theories of genome evolution.

Objectives: To investigate a population-scale comparative study of the genome-wide spectrum of sequence variants in the transgenic genome with the variations present in 3000 rice varieties.

Results: On average, we identified 19,273 SNPs (including Indels) per transgenic line in which 10,729 SNPs were at the identical locations in the three transgenic rice plants.

Transcriptomic analyses of rice (Oryza sativa) genes and non-coding RNAs under nitrogen starvation using multiple omics technologies.

Background: Nitrogen (N) is a key macronutrient essential for plant growth, and its availability has a strong influence on crop development. The application of synthetic N fertilizers on crops has increased substantially in recent decades; however, the applied N is not fully utilized due to the low N use efficiency of crops. To overcome this limitation, it is important to understand the genome-wide responses and functions of key genes and potential regulatory factors in N metabolism.

Overexpression of OsTF1L, a rice HD-Zip transcription factor, promotes lignin biosynthesis and stomatal closure that improves drought tolerance.

Drought stress seriously impacts on plant development and productivity. Improvement of drought tolerance without yield penalty is a great challenge in crop biotechnology. Here, we report that the rice (Oryza sativa) homeodomain-leucine zipper transcription factor gene, OsTF1L (Oryza sativa transcription factor 1-like), is a key regulator of drought tolerance mechanisms.

A Nitrogen Molecular Sensing System, Comprised of the and Genes, Can Be Used to Monitor N Status in Rice.

Nitrogen (N) is an essential nutrient for plant growth and development, but its concentration in the soil is often insufficient for optimal crop production. Consequently, improving N utilization in crops is considered as a major target in agricultural biotechnology. However, much remains to be learnt about crop N metabolism for application.