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Archive - Aug 18, 2014

Non-Coding RNA Involved in Regulating Internal Body Clocks

Researchers at the University of Teas (UT) Southwestern Medical Center have found a new way that internal body clocks are regulated by a type of molecule known as long non-coding RNA. The internal body clocks, called circadian clocks, regulate the daily "rhythms" of many bodily functions, from waking and sleeping to body temperature and hunger. They are largely "tuned" to a 24-hour cycle that is influenced by external cues such as light and temperature. "Although we know that long non-coding RNAs are abundant in many organisms, what they do in the body, and how they do it, has not been clear so far," said Dr. Yi Liu (image, courtesy of UT Southwestern Medical Center), Professor of Physiology. "Our work establishes a role for long non-coding RNAs in 'tuning' the circadian clock, but also shows how they control gene expression." Determining how circadian clocks work is crucial to understanding several human diseases, including sleep disorders and depression in which the clock malfunctions. The influence of a functional clock is evident in the reduced performance of shift workers and the jet lag felt by long-distance travelers. Dr. Liu and his team were able to learn more about the circadian rhythms by studying model systems involving the bread mold, Neurospora crassa. The researchers found that the expression of a clock gene named frequency (frq) is controlled by a long non-coding RNA named qrf (frq backwards) − an RNA molecule that is complementary, or antisense, to frq. Unlike normal RNA molecules, qrf does not encode a protein, but it can control whether and how much frq protein is produced. Specifically, qrf RNA is produced in response to light, and can then interfere with the production of the frq protein. In this way, qrf can "re-set" the circadian clock in a light-dependent way.

Breakthrough Technique Developed for Massive Parallel Genomic Analysis of Long DNA Molecules

Researchers from McGill University and the Génome Québec Innovation Centre have achieved a technical breakthrough that should result in speedier diagnosis of cancer and various pre-natal conditions. The key discovery, which was described online on August 4, 2014 in PNAS, lies in a new tool developed by Professors Sabrina Leslie and Walter Reisner of McGill’s Physics Department and their collaborator Dr. Rob Sladek of the Génome Québec Innovation Centre. The new tool allows researchers to load long strands of DNA into a tunable nanoscale imaging chamber in ways that maintain the strands’ structural identity and under conditions that are similar to those found in the human body. This newly developed “Convex Lens-Induced Confinement” (CLIC) will permit researchers to rapidly map large genomes, while at the same time clearly identifying specific gene sequences from single cells with single-molecule resolution, a process that is critical to diagnosing diseases like cancer. CLIC, the new tool, can sit on top of a standard inverted fluorescence microscope used in a university lab. The innovative aspect of CLIC lies in the fact that it allows strands of DNA to be loaded into the imaging chamber from above, a process which allows the strands of DNA to maintain their integrity. Existing tools used for genomic analysis rely on side-loading DNA under pressure into nanochannels in the imaging chamber, a practice that breaks the DNA molecules into small pieces, making it a challenge to reconstruct the genome. “It’s like squeezing many soft spaghetti noodles into long narrow tubes without breaking them,” explains Professor Leslie as she describes what it is like to use CLIC.

Zone in with Zon—Could Current Ebola Outbreak Have Been Prevented?

Dr. Gerald Zon’s latest “Zone in with Zon” blog post, dated August 18, 2014, and published by TriLink BioTechnologies of San Diego, discusses the topic of whether the current Ebola outbreak might have been prevented. In the course of his blog, Dr. Zon provides a wealth of information on Ebola virus and the current outbreak, as well as on various efforts to develop vaccines and treatments/drugs. He concludes that inadequate advocacy and funding, rather than inadequate science is at the root of the current inability to effectively combat the disease. As background, he cited the following statements on Ebola found on the WHO website: Ebola viral disease (EVD) is a severe, often fatal illness in humans; EVD outbreaks have a case fatality rate of up to 90%; EVD outbreaks occur primarily in remote villages in Central and West Africa, near tropical rainforests; the virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission, with infection resulting from direct contact (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids of infected people, and indirect contact with environments contaminated with such fluids; EVD is a severe acute viral illness often characterized by the sudden onset of fever, intense weakness, muscle pain, headache, and sore throat, followed by vomiting, diarrhea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding; laboratory findings include low white blood cell and platelet counts and elevated liver enzymes; severely ill patients require intensive supportive care; and no licensed specific treatment or vaccine is available for use in people or animals. Dr.