A native promoter–gene fusion created by CRISPR/Cas9-mediated genomic deletion offers a transgene-free method to drive oil accumulation in leaves

Achieving gain-of-function phenotypes without inserting foreign DNA is an important challenge for plant biotechnologists. Here we show that a gene can be brought under the control of a promoter from an upstream gene by deleting the intervening genomic sequence using dual-guide CRISPR/Cas9. We fuse the promoter of a non-essential photosynthesis-related gene to DIACYLGLYCEROL ACYLTRANSFERASE 2 (DGAT2) in the lipase-deficient sugar-dependent 1 mutant of Arabidopsis thaliana to drive ectopic oil accumulation in leaves. DGAT2 expression is enhanced more than twenty-fold and the triacylglycerol content increases by around thirty-fold. This deletion strategy offers a transgene-free route to engineering traits that rely on transcriptional gain-of-function, such as producing high lipid forage to increase the productivity and sustainability of ruminant farming

Production of human milk fat substitute by engineered strains of Yarrowia lipolytica.

Human milk fat has a distinctive stereoisomeric structure where palmitic acid is esterified to the middle (sn-2) position on the glycerol backbone of the triacylglycerol and unsaturated fatty acids to the outer (sn-1/3) positions. This configuration allows for more efficient nutrient absorption in the infant gut. However, the fat used in most infant formulas originates from plants, which exclude palmitic acid from the sn-2 position. Oleaginous yeasts provide an alternative source of lipids for human nutrition. However, these yeasts also exclude palmitic acid from the sn-2 position of their triacylglycerol. Here we show that Yarrowia lipolytica can be engineered to produce triacylglycerol with more than 60% of the palmitic acid in the sn-2 position, by expression of lysophosphatidic acid acyltransferases with palmitoyl-Coenzyme A specificity. The engineered Y. lipolytica strains can be cultured on glycerol, glucose, palm oil or a mixture of substrates, under nitrogen limited condition, to produce triacylglycerol with a fatty acid composition that resembles human milk fat, in terms of the major molecular species (palmitic, oleic and linoleic acids). Culture on palm oil or a mixture of glucose and palm oil produced the highest lipid titre and a triacylglycerol composition that is most similar with human milk fat. Our data show that an oleaginous yeast can be engineered to produce a human milk fat substitute (β-palmitate), that could be used as an ingredient in infant formulas

Deciphering the Role of Ion Channels in Early Defense Signaling against Herbivorous Insects

Plants and insect herbivores are in a relentless battle to outwit each other. Plants have evolved various strategies to detect herbivores and mount an effective defense system against them. These defenses include physical and structural barriers such as spines, trichomes, cuticle, or chemical compounds, including secondary metabolites such as phenolics and terpenes. Plants perceive herbivory by both mechanical and chemical means. Mechanical sensing can occur through the perception of insect biting, piercing, or chewing, while chemical signaling occurs through the perception of various herbivore-derived compounds such as oral secretions (OS) or regurgitant, insect excreta (frass), or oviposition fluids. Interestingly, ion channels or transporters are the first responders for the perception of these mechanical and chemical cues. These transmembrane pore proteins can play an important role in plant defense through the induction of early signaling components such as plasma transmembrane potential (Vm) fluctuation, intracellular calcium (Ca2+), and reactive oxygen species (ROS) generation, followed by defense gene expression, and, ultimately, plant defense responses. In recent years, studies on early plant defense signaling in response to herbivory have been gaining momentum with the application of genetically encoded GFP-based sensors for real-time monitoring of early signaling events and genetic tools to manipulate ion channels involved in plant-herbivore interactions. In this review, we provide an update on recent developments and advances on early signaling events in plant-herbivore interactions, with an emphasis on the role of ion channels in early plant defense signaling

Measuring the Level of Satisfaction with Respect to the Quality of Services Provided by the Local Tourist Destination in Mashhad, Iran

This paper summarizes the arguments and counterarguments within the scientific discussion on the issue of satisfaction level of tourists in Mashhad through an analytical method. The main purpose of the research is to assess the level of socio-cultural and environmental conditions and the tourist ser-vices facilities of Mashhad. Systematization literary sources and approaches for solving the problem of tourism development indicates that the tourism economy in Mashhad has special stability in terms of economic factors

Electrochemical stimuli-driven facile metal-free hydrogen evolution from pyrene-porphyrin-based crystalline covalent organic framework

A [2+2] Schiff base type condensation between 5, 10,15, 20 tetrakis(4 aminophenyl)porphyrin (TAP) and 1,3,6,8 tetrakis (4 formylphenyl) pyrene (TFFPy) under solvothermal condition yields a crystalline, quasi two dimensional covalent organic framework (SB PORPy COF). The porphyrin and pyrene units are alternatively occupied in the vertex of 3D triclinic crystal having permanent micro-porosity with moderately high surface area (~869 m2g-1) and promising chemical stability. The AA stacking of the monolayers give a pyrene bridged conducting channel. SB PORPy COF has been exploited for metal free hydrogen production to understand the electrochemical behavior using the imine based docking site in acidic media. SB PORPy-COF has shown the onset potential of 50 mV and the Tafel slope of 116 mV dec-1. We expect that the addendum of the imine based COF would not only enrich the structural variety but also help to understand the electrochemical behavior of these class of materials

Response of fenugreek (Trigonella foenum-graecum) to bio-regulators TGA and N-acetyl cystein under drip irrigation levels

Field experiments were conducted during winter seasons of 2010–11 and 2011–12 at Bikaner (Rajasthan) to study the effect of bioregulators viz., TGA and N-acetyl cystein under different drip irrigation levels on yield, yield attributes, water use and water use efficiency of fenugreek. The highest plant height (69 cm) and yield attributes viz., branches plant-1 (7.6), pods plant-1 (46.3), pod length (13.5 cm), seed pod-1 (16) and test weight (12.7 g) were recorded with 100% ETc + TGA (200 ppm). Further, 80% ETc + TGA (200 ppm), and 100% ETc + N-acetyl cystein (both 10 and 20 ppm) and 100% ETc + TGA (both 100 and 200 ppm) produced comparable plant height. However, 80% ETc + N-acetyl cystein (both 10 and 20 ppm), 80% ETc + TGA (both 100 and 200 ppm), 100% ETc + N-acetyl cystein (both 10 and 20 ppm), 100% ETc + TGA (100 ppm) and 100% ETc + TGA (200 ppm) recorded at par branches plant-1, pods plant-1, pod length and test weight of fenugreek. Highest seed and biological yield of fenugreek were recorded with 100% ETc + Nacetyl cystein (20 ppm), which was at par with 100% ETc + N-acetyl cystein (10 ppm) and 100% ETc + TGA (both 100 and 200 ppm). Maximum water use recorded at 100% ETc with or without bioregulators, whereas maximum water use efficiency was recorded with 60% ETc + N-acetyl cystein (20 ppm) followed by 60% ETc + N-acetyl cystein (10 ppm). &nbsp

Effect of irrigation and nitrogen on water use, moisture extraction pattern, nitrogen uptake and yield of coriander (Coriandrum sativum L.) in north-western irrigated plains of Rajasthan

An experiment was conducted at Sriganganagar (Rajasthan) to study water use, water useefficiency, nitrogen uptake, yield and economics of coriander (Coriandrum sativum) cultivars(RCr 41, RCr 435) under various levels of nitrogen (20, 40 and 60 kg ha-1) and irrigation (IW/CPE ratios 0.6, 0.8 and irrigation at branching + flowering + seed formation stages). Thehighest seed yield (10.98 q ha-1), yield attributes and benefit: cost ratio (2.65) were recordedwith 60 kg nitrogen ha-1. Increasing levels of nitrogen also recorded higher consumptive useof water and nitrogen uptake. Plants under higher levels of nitrogen (60 kg ha-1) extractedmore water from the lower depth (60-90 cm) than lower level of nitrogen (20 kg ha-1). Increasein irrigation frequency significantly enhanced the yield and yield attributes of both thecultivars. Similarly, water use, nitrogen uptake and benefit:cost ratio were also higher withhigher levels of irrigation. &nbsp