Maternally expressed FERTILIZATION-INDEPENDENT ENDOSPERM1 regulates seed dormancy and aleurone development in rice.

Seed dormancy, an essential trait for plant adaptation, is determined by the embryo itself and the surrounding tissues. Here, we found that rice (Oryza sativa) FERTILIZATION-INDEPENDENT ENDOSPERM1 (OsFIE1) regulates endosperm-imposed dormancy and the dorsal aleurone thickness in a manner dependent on the parent of origin. Maternally expressed OsFIE1 suppresses gibberellin (GA) biosynthesis in the endosperm by depositing trimethylation of lysine 27 on histone H3 (H3K27me3) marks on GA biosynthesis-related genes, thus inhibiting germination and aleurone differentiation.

A chloroplast localized heavy metal-associated domain containing protein regulates grain calcium accumulation in rice.

Calcium (Ca) is an essential mineral nutrient and plays a crucial signaling role in all living organisms. Increasing Ca content in staple foods such as rice is vital for improving Ca nutrition of humans. Here we map a quantitative trait locus that controls Ca concentration in rice grains and identify the causal gene as GCSC1 (Grain Ca and Sr Concentrations 1), which encodes a chloroplast vesicle localized homo-oligomeric protein.

The OsZIP2 transporter is involved in root-to-shoot translocation and intervascular transfer of cadmium in rice.

Cadmium (Cd) is a toxic metal that poses serious threats to human health. Rice is a major source of dietary Cd but how rice plants transport Cd to the grain is not fully understood. Here, we characterize the function of the ZIP (ZRT, IRT-like protein) family protein, OsZIP2, in the root-to-shoot translocation of Cd and intervascular transfer of Cd in nodes.

OsCOPT7 is a copper exporter at the tonoplast and endoplasmic reticulum and controls Cu translocation to the shoots and grain of rice.

Copper (Cu) is an essential micronutrient for all living organisms but is also highly toxic in excess. Cellular homoeostasis of Cu is maintained by various transporters and metallochaperones. Here, we investigated the biological function of OsCOPT7, a member of the copper transporters (COPT) family, in Cu homoeostasis in rice.

IAR4 mutation enhances cadmium toxicity by disturbing auxin homeostasis in Arabidopsis thaliana.

Cadmium (Cd) is highly toxic to plants, but the targets and modes of toxicity remain unclear. We isolated a Cd-hypersensitive mutant of Arabidopsis thaliana, Cd-induced short root 2 (cdsr2), in the background of the phytochelatin synthase-defective mutant cad1-3. Both cdsr2 and cdsr2 cad1-3 displayed shorter roots and were more sensitive to Cd than their respective wild type.

Combined genomics to discover genes associated with tolerance to soil carbonate.

Carbonate-rich soils limit plant performance and crop production. Previously, local adaptation to carbonated soils was detected in wild Arabidopsis thaliana accessions, allowing the selection of two demes with contrasting phenotypes: A1 (carbonate tolerant, c+) and T6 (carbonate sensitive, c-). Here, A1 and T6 seedlings were grown hydroponically under control (pH 5.

Sulfate-TOR signaling controls transcriptional reprogramming for shoot apex activation.

Plants play a primary role for the global sulfur cycle in the earth ecosystems by reduction of inorganic sulfate from the soil to organic sulfur-containing compounds. How plants sense and transduce the sulfate availability to mediate their growth remains largely unclear. The target of rapamycin (TOR) kinase is an evolutionarily conserved master regulator of nutrient sensing and metabolic signaling to control cell proliferation and growth in all eukaryotes.

New traction method (traction ring) for colorectal endoscopic submucosal dissection.

Objectives: Colorectal endoscopic submucosal dissection (ESD) is challenging because of the difficulty in adequately visualizing the submucosal layer. Many traction methods have been developed to facilitate submucosal dissection; however, they are not widely applied. Therefore, we designed a new traction device, a traction ring, and conducted this pilot study to evaluate its feasibility and safety for colorectal ESD.

Local and Systemic Response to Heterogeneous Sulfate Resupply after Sulfur Deficiency in Rice.

Sulfur (S) is an essential mineral nutrient required for plant growth and development. Plants usually face temporal and spatial variation in sulfur availability, including the heterogeneous sulfate content in soils. As sessile organisms, plants have evolved sophisticated mechanisms to modify their gene expression and physiological processes in order to optimize S acquisition and usage.

Sulfur Compounds in Regulation of Stomatal Movement.

Sulfur, widely present in the soil and atmosphere, is one of the essential elements for plants. Sulfate is a dominant form of sulfur in soils taken up by plant roots. In addition to the assimilation into sulfur compounds essential for plant growth and development, it has been reported recently that sulfate as well as other sulfur containing compounds can also induce stomatal movement.

The Vacuolar Molybdate Transporter OsMOT1;2 Controls Molybdenum Remobilization in Rice.

Molybdenum (Mo) is an essential micronutrient for almost all living organisms. The Mo uptake process in plants has been well investigated. However, the mechanisms controlling Mo translocation and remobilization among different plant tissues are largely unknown, especially the allocation of Mo to rice grains that are the major dietary source of Mo for humans.

Molybdenum: More than an essential element.

Molybdenum (Mo) is an essential element for almost all living organisms. After being taken up into the cells as molybdate, it is incorporated into the molybdenum cofactor, which functions as the active site of several molybdenum-requiring enzymes and thus plays crucial roles in multiple biological processes. The uptake and transport of molybdate is mainly mediated by two types of molybdate transporters.

Toxic metals and metalloids: Uptake, transport, detoxification, phytoremediation, and crop improvement for safer food.

Agricultural soils are under threat of toxic metal/metalloid contamination from anthropogenic activities, leading to excessive accumulation of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) in food crops that poses significant risks to human health. Understanding how these toxic metals and their methylated species are taken up, translocated, and detoxified is prerequisite to developing strategies to limit their accumulation for safer food. Toxic metals are taken up and transported across different cellular compartments and plant tissues via various transporters for essential or beneficial nutrients, e.

A molecular switch in sulfur metabolism to reduce arsenic and enrich selenium in rice grain.

Rice grains typically contain high levels of toxic arsenic but low levels of the essential micronutrient selenium. Anthropogenic arsenic contamination of paddy soils exacerbates arsenic toxicity in rice crops resulting in substantial yield losses. Here, we report the identification of the gain-of-function arsenite tolerant 1 (astol1) mutant of rice that benefits from enhanced sulfur and selenium assimilation, arsenic tolerance, and decreased arsenic accumulation in grains.

Univariate and Multivariate QTL Analyses Reveal Covariance Among Mineral Elements in the Rice Ionome.

Rice provides more than one fifth of daily calories for half of the world's human population, and is a major dietary source of both essential mineral nutrients and toxic elements. Rice grains are generally poor in some essential nutrients but may contain unsafe levels of some toxic elements under certain conditions. Identification of quantitative trait loci (QTLs) controlling the concentrations of mineral nutrients and toxic trace metals (the ionome) in rice will facilitate development of nutritionally improved rice varieties.

High-Affinity Sulfate Transporter Sultr1;2 Is a Major Transporter for Cr(VI) Uptake in Plants.

Chromate (Cr[VI]) is a highly phytotoxic contaminant that is ubiquitous in soils. However, how Cr(VI) is taken up by plant roots remains largely unknown. Here, we show that the high-affinity sulfate transporter Sultr1;2 is responsible for Cr(VI) uptake by the roots of .

Cadmium Inhibits Lateral Root Emergence in Rice by Disrupting OsPIN-Mediated Auxin Distribution and the Protective Effect of OsHMA3.

Cadmium (Cd) strongly inhibits root growth, especially the formation of lateral roots (LRs). The mechanism of Cd inhibition on LR formation in rice (Oryza sativa) remains unclear. In this study, we found that LR emergence in rice was inhibited significantly by 1 �M Cd and almost completely arrested by 5 �M Cd.

Overexpression of Rice in Wheat Greatly Decreases Cadmium Accumulation in Wheat Grains.

Cereals are a major dietary source of the toxic metal cadmium (Cd). Reducing Cd accumulation in cereal crops such as wheat () is important for food safety and human health. In this study, we show that three diverse cultivars of wheat had a high Cd translocation from roots to shoots, similar to a rice () cultivar possessing a nonfunctional tonoplast Cd transporter OsHMA3.

Overexpression of the manganese/cadmium transporter OsNRAMP5 reduces cadmium accumulation in rice grain.

Rice is a major dietary source of the toxic metal cadmium (Cd), and reducing its accumulation in the grain is therefore important for food safety. We selected two cultivars with contrasting Cd accumulation and generated transgenic lines overexpressing OsNRAMP5, which encodes a major influx transporter for manganese (Mn) and Cd. We used two different promoters to control the expression, namely OsActin1 and maize Ubiquitin.

OASTL-A1 functions as a cytosolic cysteine synthase and affects arsenic tolerance in rice.

Arsenic (As) contamination in paddy soil can cause phytotoxicity and elevated As accumulation in rice grains. Arsenic detoxification is closely linked to sulfur assimilation, but the genes involved have not been described in rice. In this study, we characterize the function of OASTL-A1, an O-acetylserine(thiol) lyase, in cysteine biosynthesis and detoxification of As in rice.

QTL pyramiding for producing nutritious and safe rice grains.

Breeding of rice varieties that are enriched with essential micronutrients and simultaneously have reduced levels of toxic elements in grains is largely unexplored in rice breeding practice. In this issue of JIPB, Liu et al. (2020) developed two rice lines with a low level of cadmium and simultaneously high levels of zinc or selenium accumulation in the grains, thus providing elite genetic materials for breeding rice varieties that are important for addressing mineral malnutrition and ensuring food safety.

Mutation in OsCADT1 enhances cadmium tolerance and enriches selenium in rice grain.

How cadmium (Cd) tolerance in rice is regulated remains poorly understood. We used a forward genetic approach to investigate Cd tolerance in rice. Using a root elongation assay, we isolated a rice mutant with enhanced Cd tolerance, cadt1, from an ethyl methanesulphonate (EMS)-mutagenized population of a widely grown Indica cultivar.

Genetic mapping of ionomic quantitative trait loci in rice grain and straw reveals OsMOT1;1 as the putative causal gene for a molybdenum QTL qMo8.

Rice is a major dietary source of essential mineral nutrients and toxic elements (aka ionome) for humans. However, the genetic basis underlying the variation in ionome is still largely unknown. Here, we mapped 51 and 61 quantitative trait loci (QTLs) controlling the concentrations of 13 and 15 elements in rice (Oryza sativa L.

Variation in the BrHMA3 coding region controls natural variation in cadmium accumulation in Brassica rapa vegetables.

Brassica rapa includes several important leafy vegetable crops with the potential for high cadmium (Cd) accumulation, posing a risk to human health. This study aims to understand the genetic basis underlying the variation in Cd accumulation among B. rapa vegetables.