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O,.o Circa 2019

CRISPR/Cas9 is now a household name associated with genetic engineering studies. Through cutting-edge research described in their paper published in Scientific Reports, a team of researchers from Tokyo University of Science, Meiji University, and Tokyo University of Agriculture and Technology, led by Dr Takayuki Arazoe and Prof Shigeru Kuwata, has recently established a series of novel strategies to increase the efficiency of targeted gene disruption and new gene “introduction” using the CRISPR/Cas9 system in the rice blast fungus Pyricularia (Magnaporthe) oryzae. These strategies include quicker (single-step) gene introduction, use of small homologous sequences, and bypassing of certain prerequisite host DNA “patterns” and host component modification.

The team led by Dr Arazoe and Prof Kuwata has devised simple and quick techniques for gene editing (target gene disruption, sequence substitution, and re-introduction of desired genes) using CRISPR/Cas9 in the rice blast fungus Pyricularia (Magnaporthe) oryzae, a type of filamentous fungus. Spurred on by encouraging results, the researchers surmise, “Plants and their pathogens are still coevolving in nature. Exploiting the mutation mechanisms of model pathogenic fungi as a genome editing technique might lead to the development of further novel techniques in genetic engineering.”

The working component of the CRISPR/Cas9 system binds to the target gene region (DNA) and causes a site-specific double-stranded break (DSB) in the DNA. Effective binding of this component requires a certain “motif” or “pattern” called the protospacer-adjacent motif (PAM), which follows downstream of the target gene region.

For more than two decades, I have been working to improve several staple food crops in Africa, including bananas, plantains, cassavas and yams. As principal scientist and a plant biotechnologist at the International Institute for Tropical Agriculture in Nairobi, I aim to develop varieties that are resistant to pests and diseases such as bacterial wilt, Fusarium wilt (caused by the fungus F. oxysporum) and banana streak virus.

[Editor’s note: Abdullahi Tsanni is a freelance science journalist based in Abuja, Nigeria.]

In 2011, my team and I created a set of tools, the only one of its kind in Africa, for changing DNA sequences so that we could develop genetically modified and genome-edited products in sub-Saharan Africa. In 2018, we pioneered the first application of CRISPR gene-editing technology to deactivate banana streak virus in plantains. This technology overcame a major hurdle in banana breeding on the continent, and is the first reported successful use of genome editing to improve bananas.

The honeybee (Apis mellifera) is an important insect pollinator of wild flowers and crops, playing critical roles in the global ecosystem. Additionally, the honeybee serves as an ideal social insect model. Therefore, functional studies on honeybee genes are of great interest. However, until now, effective gene manipulation methods have not been available in honeybees. Here, we reported an improved CRISPR/Cas9 gene-editing method by microinjecting sgRNA and Cas9 protein into the region of zygote formation within 2 hr after queen oviposition, which allows one-step generation of biallelic knockout mutants in honeybee with high efficiency. We first targeted the Mrjp1 gene. Two batches of honeybee embryos were collected and injected with Mrjp1 sgRNA and Cas9 protein at the ventral cephalic side and the dorsal posterior side of the embryos, respectively. The gene-editing rate at the ventral cephalic side was 93.3%, which was much higher than that (11.8%) of the dorsal-posterior-side injection. To validate the high efficiency of our honeybee gene-editing system, we targeted another gene, Pax6, and injected Pax6 sgRNA and Cas9 protein at the ventral cephalic side in the third batch. A 100% editing rate was obtained. Sanger sequencing of the TA clones showed that 73.3% (for Mrjp1) and 76.9% (for Pax6) of the edited current-generation embryos were biallelic knockout mutants. These results suggest that the CRISPR/Cas9 method we established permits one-step biallelic knockout of target genes in honeybee embryos, thereby demonstrating an efficient application to functional studies of honeybee genes. It also provides a useful reference to gene editing in other insects with elongated eggs.

Clustered regularly interspaced short palindromic repeats (CRISPR) and the CRISPR-associated gene Cas9 represent an invaluable system for the precise editing of genes in diverse species. The CRISPR/Cas9 system is an adaptive mechanism that enables bacteria and archaeal species to resist invading viruses and phages or plasmids. Compared with zinc finger nucleases and transcription activator-like effector nucleases, the CRISPR/Cas9 system has the advantage of requiring less time and effort. This efficient technology has been used in many species, including diverse arthropods that are relevant to agriculture, forestry, fisheries, and public health; however, there is no review that systematically summarizes its successful application in the editing of both insect and non-insect arthropod genomes. Thus, this paper seeks to provide a comprehensive and impartial overview of the progress of the CRISPR/Cas9 system in different arthropods, reviewing not only fundamental studies related to gene function exploration and experimental optimization but also applied studies in areas such as insect modification and pest control. In addition, we also describe the latest research advances regarding two novel CRISPR/Cas systems (CRISPR/Cpf1 and CRISPR/C2c2) and discuss their future prospects for becoming crucial technologies in arthropods.

Keywords: CRISPR/Cas9, insects, non-insect arthropods, research progress, prospects.

Genome editing technologies are useful for understanding the functions of target genes in diverse organisms (Segal and Meckler, 2013). Before the CRISPR/Cas9 system was discovered, zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs) technologies were used for genome modification; both technologies can be used to design a DNA-binding domain that can effectively recognize and modify virtually any sequence, and both technologies have been widely applied in various fields (Gaj et al., 2013). ZFNs and TALENs, however, require the use of a variety of nucleases, and the off-target effects of nucleases can lead to cellular toxicity. In addition, methods using ZFNs and TALENs are complex and labor-intensive (Kanchiswamy et al., 2016). These two genome-editing systems have been recently replaced by the CRISPR/Cas9 system, which is far more convenient and effective than ZFNs and TALENs (Lander, 2016; Mohanraju et al., 2016; Wang H. et al., 2016; Westra et al.

Multilayer plastic materials are ubiquitous in food and medical supply packaging, particularly since layering polymers can give those films specific properties, like heat resistance or oxygen and moisture control. But despite their utility, those ever-present plastics are impossible to recycle using conventional methods.

About 100 million tons of multilayer thermoplastics — each composed of as many as 12 layers of varying polymers — are produced globally every year. Forty percent of that total is waste from the manufacturing process itself, and because there has been no way to separate the polymers, almost all of that plastic ends up in landfills or incinerators.

Now, University of Wisconsin-Madison engineers have pioneered a method for reclaiming the polymers in these materials using solvents, a technique they’ve dubbed Solvent-Targeted Recovery and Precipitation (STRAP) processing. Their proof-of-concept is detailed today (November 20, 2020) in the journal Science Advances.

https://www.forbes.com/sites/johnkoetsier/2020/11/20/this-2-…f7a547a57c to Nate Storey, the future of farms is vertical. It’s also indoors, can be placed anywhere on the planet, is heavily integrated with robots and AI, and produces better fruits and vegetables while using 95% less water and 99% less land.

95% less water. 99% less land. 400X more yield.

Here’s my latest video!

Animal products, including meat, cheese, and eggs contain carnitine and choline, metabolites that are converted by gut bacteria into TMA, which is then converted by the liver into TMAO. Plasma levels of TMAO are associated with an increased risk of disease and death, so should we limit intake of these animal products?

Continue reading “Kidney Function: The Missing Link In The TMAO-Health And Disease Story?” »

The world’s first restaurant experience that provides clientele the opportunity to eat meat grown directly from chicken cells has been opened in the Israeli town of Ness Ziona.

Scanning lasers—from barcode scanners at the supermarket to cameras on newer smartphones—are an indispensable part of our daily lives, relying on lasers and detectors for pinpoint precision.

Distance and object recognition using LiDAR—a portmanteau of light and radar—is becoming increasingly common: reflected laser beams record the surrounding environment, providing crucial data for autonomous cars, agricultural machines, and factory robots.

Current technology bounces the laser beams off of moving mirrors, a mechanical method that results in slower scanning speeds and inaccuracies, not to mention the large physical size and complexity of devices housing a laser and mirrors.