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Showing posts with the label Biotechnology and Bioengineering

Genome-Edited Plants

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Genome-Edited Plants, Without DNA What makes this work so groundbreaking is that these genetic modifications look just like genetic variations resulting from the selective breeding that farmers have been doing for millennia. IBS Director of the Center for Genome Engineering Jin-Soo Kim explains that "the targeted sites contained germ line-transmissible small insertions or deletions that are indistinguishable from naturally occurring genetic variation." CRISPR is an acronym for Clustered Regularly Interspaced Short Palindromic Repeat, which refers to the unique repeated DNA sequences found in bacteria and archaea. CRISPR is now used widely for genome editing. What's crucial in genetic engineering is for the gene editing tool to be accurate and precise, which is where CRISPR-Cas9 excels. CRISPR-Cas9 uses a single guide RNA (sgRNA) to identify and edit the target gene and Cas9 (a protein) then cleaves the gene, resulting in site-specific DNA double-strand breaks (...

Sensor Could Detect Viruses, Kill Cancer Cells

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Sensor Could Detect Viruses, Kill Cancer Cells This system can be customized to detect any DNA sequence in a mammalian cell and then trigger a desired response, including killing cancer cells or cells infected with a virus, the researchers say. "There is a range of applications for which this could be important," says James Collins, the Termeer Professor of Medical Engineering and Science in MIT's Department of Biological Engineering and Institute of Medical Engineering and Science (IMES). "This allows you to readily design constructs that enable a programmed cell to both detect DNA and act on that detection, with a report system and/or a respond system." Collins is the senior author of a Sept. 21 Nature Methods paper describing the technology, which is based on a type of DNA-binding proteins known as zinc fingers. These proteins can be designed to recognize any DNA sequence. "The technologies are out there to engineer proteins to bind to vir...

Blocking Differentiation is Enough to Give Cells 'Stemness'

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Blocking Differentiation is Enough to Give Cells 'Stemness' Efforts in the past to create stem cells have typically involved finding ways to take target cells and "dedifferentiate" them into multipotent cells, but this is typically a painstaking process. According to Tomokatsu Ikawa, the first and corresponding author of the paper published in Stem Cell Reports, "We decided to look at the possibility that somatic stem cells could be maintained in a stem cell-like state where they could proliferate without undergoing differentiation." To test this, the team took mouse hematopoietic progenitor cells--cells that give rise to white blood cells--and modified them to overexpress a protein called Id3. Id3 inhibits the expression of E-proteins, which are involved in differentiation in somatic cells. They then placed the cells into culture conditions containing certain cytokines, and instead of differentiating into B-cells, the cells continued to divide as ste...

Microbiomes Could Hold Keys to Improving Life

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Microbiomes Could Hold Keys to Improving Life Microbial life forms including viruses, bacteria and fungi are the most diverse and abundant organisms on earth. They have shaped our evolutionary origins for billions of years and continue to have widespread impact on the planet, its environment and the species inhabiting it. Together, they make up microbiomes that influence each other, the environment, and the host organisms that these microbial communities thrive in. The UMIC foresees that the microbiomes populating our planet and its many diverse species and environments could be leveraged through genetic engineering for applications that improve the greater good, and that many milestones could be reached on this front within ten years. "Microbes are everywhere. Therefore understanding microbiomes, whether they be the ones that live in and on our bodies or the ones in the environment, is essential to understanding life," said Silver, who in addition to being one...

A cure for Vitamin B6 Deficiency

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A cure for Vitamin B6 Deficiency In many tropical countries, particularly in sub-Saharan Africa, cassava is one of the most important staple foods. People eat the starchy storage roots but also the leaves as a vegetable. Both have to be cooked first to remove the toxic cyanide compounds that cassava produces. But the roots have a disadvantage: although rich in calories, in general they contain only few vitamins. Vitamin B6 in particular is present in only small amounts, and a person for whom cassava is a staple food would have to eat about 1.3 kg of it every day for a sufficient amount of this vital vitamin. Serious deficiency in Africa Vitamin B6 deficiency is prevalent in several African regions where cassava is often the only staple food people's diet. Diseases of the cardiovascular and nervous systems as well as are associated with vitamin B6 deficiency. Plant scientists at ETH Zurich and the University of Geneva have therefore set out to find a way to increase ...

Cellular Stress Management in People and Plants

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Cellular Stress Management in People and Plants Proteins have many tasks to fulfil in the structure, function and regulation of cells. Once the proteins are formed, they are further adapted for their very specific jobs. "One of the most frequent changes is the attachment of an acetic acid residue on the amino-terminal end of the proteins. Lacking this modification, the plants cannot survive, and this same lack in certain proteins in humans leads to illness, developmental problems and cell death," explains Prof. Hell. Although up to 80 percent of proteins in the cytoplasm of human cells are modified by an acetic acid residue at their amino terminus, the function of this modification has only been studied for a handful of proteins. The Heidelberg researchers generated genetically modified plants with protein populations that carry less acetic acid residues and analyzed the results. "The changed pattern of amino-terminal modification proteins by acetic acid surpr...