Biology News Net - Molecular & Cell Biology

How DNA finds its match

Wed, 08 Feb 2012 16:44:38 -0500

This graphic shows DNA strung between two beads, which are held in position by laser. It's been more than 50 years since James Watson and Francis Crick showed that DNA is a double helix of two strands that complement each other. But how does a short piece of DNA find its match, out of the millions of 'letters' in even a small genome? New work by researchers at the University of California, Davis, handling and observing single molecules of DNA, shows how it's done. The results are published online Feb. 8 by the journal Nature.

Sharp images from the living mouse brain

Mon, 06 Feb 2012 17:29:25 -0500

This STED image of a nerve cell in the upper brain layer of a living mouse shows in previously impossible detail the very fine dendritic protrusions of a nerve cell To explore the most intricate structures of the brain in order to decipher how it functions – Stefan Hell's team of researchers at the Max Planck Institute for Biophysical Chemistry in Göttingen has made a significant step closer to this goal. Using the STED microscopy developed by Hell, the scientists have, for the first time, managed to record detailed live images inside the brain of a living mouse. Captured in the previously impossible resolution of less than 70 nanometers, these images have made the minute structures visible which allow nerve cells to communicate with each other. This application of STED microscopy opens up numerous new possibilities for neuroscientists to decode fundamental processes in the brain.

Parasites or not? Transposable elements in fruit flies

Fri, 03 Feb 2012 20:28:56 -0500

Nearly all organisms contain pieces of DNA that do not really belong to them. These "transposable elements", so called because they are capable of moving around within and between genomes, generally represent a drain on the host's resources and in certain cases may lead directly to disease, e.g. when they insert themselves within an essential host gene. The factors that govern the spread of transposable elements within a population are broadly understood but many of the finer points remain unclear. New work at the University of Veterinary Medicine, Vienna (Vetmeduni Vienna) may pave the way to a more profound knowledge of the intracellular battle that is constantly being played out between the host and invading DNA.

Surprise finding redraws 'map' of blood cell production

Tue, 31 Jan 2012 18:54:13 -0500

Drs Maria Kauppi (left) and Ashley Ng from the Walter and Eliza Hall Institute in Melbourne, Australia, study blood 'progenitor' cells A study of the cells that respond to crises in the blood system has yielded a few surprises, redrawing the 'map' of how blood cells are made in the body.

Biological time-keeper linked to diabetes

Mon, 30 Jan 2012 16:49:20 -0500

Researchers in Lille and Paris demonstrated that mutations in the melatonin receptor gene (melatonin or the "hormone of darkness" induces sleep) lead to an almost sevenfold increase in the risk of developing diabetes. This research, which was published in Nature Genetics on 29 January 2012, could contributed to the development of new drugs for the treatment or prevention of this metabolic disease.

Membrane fusion a mystery no more

Tue, 24 Jan 2012 17:58:45 -0500

The many factors that contribute to how cells communicate and function at the most basic level are still not fully understood, but researchers at Baylor College of Medicine have uncovered a mechanism that helps explain how intracellular membranes fuse, and in the process, created a new physiological membrane fusion model.

Life discovered on dead hydrothermal vents

Tue, 24 Jan 2012 17:58:40 -0500

Scientists at USC have uncovered evidence that even when hydrothermal sea vents go dormant and their blistering warmth turns to frigid cold, life goes on.

New discoveries in cell aging

Mon, 23 Jan 2012 17:22:00 -0500

A group of researchers led by the Institute of Biotechnology and Biomedicine (IBB) and Universitat Autònoma de Barcelona (UAB) have achieved to quantify with precision the effect of protein aggregation on cell aging processes using as models the Escherichia coli bacteria and the molecule which triggers Alzheimer's disease. Scientists demonstrated that the effect can be predicted before it occurs. Protein aggregation is related to several diseases, including neurodegenerative diseases.

How cells dispose of their waste

Mon, 23 Jan 2012 17:21:57 -0500

The "regulatory particle " (in blue) detects the proteins tagged with ubiquitin and prepares them for degradation. The "core particle " (in red) breaks the proteins down into their single components. Defective proteins that are not disposed of by the body can cause diseases such as Alzheimer's or Parkinson's. Scientists at the Max Planck Institute (MPI) of Biochemistry recently succeeded in revealing the structure of the cellular protein degradation machinery (26S proteasome) by combining different methods of structural biology. The results of collaboration with colleagues from the University of California, San Francisco and the Swiss Federal Institute of Technology Zurich (ETH Zürich) represent an important step forward in the investigation of the 26S proteasome. The findings have now been published in Proceedings of the National Academy of Sciences.

Defective cell 'battery' plays central role in neurodegenerative disease

Tue, 17 Jan 2012 16:17:36 -0500

A devastating neurodegenerative disease that first appears in toddlers just as they are beginning to walk has been traced to defects in mitochondria, the 'batteries' or energy-producing power plants of cells. This finding by a team of researchers, led by investigators from the Montreal Neurological Institute and Hospital – The Neuro- at McGill University, was published in this week's issue of the Proceedings of the National Academy of Sciences of the USA (PNAS). The research, which was highlighted as "Novel & Newsworthy" by the American Society for Cell Biology (ASCB), significantly increases understanding of the disease and reveals an important common link with other neurodegenerative diseases, providing renewed hope and potential new therapeutic strategies for those affected around the world.