News tagged with mechanical properties
Related topics: graphene , carbon nanotube
DNA structure shows a variety of forms, both double-stranded and single-stranded. The mechanical properties of DNA, which are directly related to its structure, are a significant problem for cells. Every process which binds or reads DNA is able to use or modify the mechanical properties of DNA for purposes of recognition, packaging and modification. The extreme length (a chromosome may contain a 10 cm long DNA strand), relative rigidity and helical structure of DNA has led to the evolution of histones and of enzymes such as topoisomerases and helicases to manage a cell's DNA. The properties of DNA are closely related to its molecular structure and sequence, particularly the weakness of the hydrogen bonds and electronic interactions that hold strands of DNA together compared to the strength of the bonds within each strand.
Experimental techniques which can directly measure the mechanical properties of DNA are relatively new, and high-resolution visualization in solution is often difficult. Nevertheless, scientists have uncovered large amount of data on the mechanical properties of this polymer, and the implications of DNA's mechanical properties on cellular processes is a topic of active current research.
It is important to note the DNA found in many cells can be macroscopic in length - a few centimetres long for each human chromosome. Consequently, cells must compact or "package" DNA to carry it within them. In eukaryotes this is carried by spool-like proteins known as histones, around which DNA winds. It is the further compaction of this DNA-protein complex which produces the well known mitotic eukaryotic chromosomes.
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A researcher at The Feinstein Institute for Medical Research has discovered additional mechanical properties of articular cartilage, a protective cartilage on the ends of bones that wears down over time, resulting in the ...
Arthritis & Rheumatism Apr 19, 2013 | not rated yet | 0
(Medical Xpress)—Research carried out by Professor Barbara Pierscionek and a team of fellow vision experts suggests that the way proteins are distributed in the lens of the eye may cause its gradient to ...
Ophthalmology Mar 01, 2013 | 5 / 5 (1) | 0
Light-sensing cells in the eye rely on their outer segment to convert light into neural signals that allow us to see. But because of its unique cylindrical shape, the outer segment is prone to breakage, which ...
Medical research Jan 22, 2013 | 5 / 5 (3) | 0 |
MRI brain scans no longer just show the various regions of brain activity; nowadays the networks in the brain can now be imaged with ever greater precision. This will make functional MRI (fMRI) increasingly ...
Neuroscience Sep 18, 2012 | 5 / 5 (1) | 0
Adult stem cells extracted during liposuction can be used to grow healthy new small-diameter blood vessels for use in heart bypass surgery and other procedures, according to new research presented at the American Heart Association's ...
Cardiology Jul 25, 2012 | not rated yet | 0
(Medical Xpress) -- Scientists at the University of Reading have made a significant breakthrough in cornea transplant research that could make future procedures more successful.
Ophthalmology Jul 06, 2012 | not rated yet | 0 |
Fear conditioning using sound and taste aversion, as applied to mice, have revealed interesting information on the basis of memory allocation.
Neuroscience Jun 18, 2012 | 3 / 5 (1) | 0
High fat diets cause damage to blood vessels earlier than previously thought, and these structural and mechanical changes may be the first step in the development of high blood pressure. These findings in mice, by Marie Billaud ...
Cardiology Apr 03, 2012 | 1.6 / 5 (8) | 3 |
A hard probe inserted in the cerebral cortex of a rat model turns nearly as pliable as the surrounding gray matter in minutes, and induces less of the tough scarring that walls off hard probes that do not change, researchers ...
Neuroscience Nov 03, 2011 | 5 / 5 (1) | 0