DNA has the nasty habit of getting tangled and forming knots. Scientists study these knots to understand their function and learn how to disentangle them (e.g. useful for gene sequencing techniques). Cristian Micheletti, professor at the International School for Advanced Studies (SISSA) in Trieste and his team have been carrying out research in which they simulate these knots and their dynamics. In their latest paper, just published in the journal Soft Matter, Micheletti together with Marco Di Stefano, first author and PhD student at SISSA, and colleagues from Ljubljana and San Diego devised and tested a method based on the application of electric fields and "optical tweezers." DNA is in fact an electrically charged molecule which reacts to the presence of opposing charges. "In our theoretical-computational study we took into account a "stretched-out" strand of DNA, with its ends secured by two optical tweezers that serve as anchors to keep them apart. We succeeded in moving the knot, inserted into the configuration, by applying an electric field," explains Micheletti. "Try to imagine holding one end of a knotted rope so that the rope is suspended above the ground: by shaking it gently you can make the knot slide down with … Continue reading →

July 24, 2014 The DNA samples taken were from the next-of-kin with biological ties, such as parents, children and siblings. PETALING JAYA: The Health Ministry has taken 45 DNA samples from the next-of-kin of those who died in the MH17 crash. Health Minister Datuk Seri Dr. S. Subramaniam said two more samples were still in the process of being taken from two families. MAS informed that 43 of the victims have family ties in Malaysia, he said in a statement Thursday. Dr.Subramaniam said there were victims who lived overseas but had family ties in Malaysia, bringing the number of families involved in ante mortem Disaster Victim Identification (DVI) and DNA sample data collection to 47. The DNA samples taken were from the next-of-kin with biological ties, such as parents, children and siblings. The views expressed in the contents are those of our users and do not necessarily reflect the views of FMT. Read the original: 45 DNA samples taken from next-of-kin … Continue reading →

Contact Information Available for logged-in reporters only Human cells make new copies of their DNA billions of times each day, a crucial process upon which life itself depends. However, scientists do not fully understand how cells unzip the double-stranded DNA molecule before replicating both halves of it. New work at Rockefeller may help change that. For the first time, researchers in Michael ODonnells Laboratory of DNA Replication have built a model that can enable scientists to study what happens at the replication fork the point where the DNA molecule is split down the middle in order to create an exact copy of each side. As a research tool, our model could help scientists better address basic biological questions about cell division, as well as the nature of errors that cause diseases, such as cancer, ODonnell says. There are plenty of hypotheses about the mechanics of DNA replication, but until now the process could not be studied using a defined system with pure proteins. The findings, published July 6 in the journal Nature Structural and Molecular Biology, focus on eukaryotic cells. All multicellular life, including humans, is eukaryotic. Single-celled prokaryotes evolved a different method for replicating their DNA. In order to … Continue reading →

A vegan-friendly cheese has been created in a lab using strands of human DNA and baker's yeast. San Francisco-based iGem group said it found a way to make cheese proteins using genetic sequences found in mammals. The DNA blueprints are inserted into the yeast, which creates cheese that is vegan-compatible because of the lack of animal products. Some of the DNA strands are from humans, because the developers hope milk proteins made from our own species will mean less chance of allergic reactions. iGem has now hit its $US15,000 goal on the Indiegogo crowdfunding website, to develop the cheese for mass market. It claims that the product is the first vegan cheese - rather than a cheese substitute. On its fundraising page, iGem said: 'To create our proteins, we study animal genomes to find natural milk-protein genetic sequences. 'We optimise the genes for use in yeast and synthesise the resulting yeast milk protein DNA from scratch. 'This DNA is then put into yeast cells where the cellular machinery takes over and produces real milk-protein from the DNA blueprint provided by us.' The company said it 'may be a while' before the finished product is ready for sale. See more here: … Continue reading →