Electronics & Semiconductors

Implantable device can monitor and treat heart disease

Pacemakers and other implantable cardiac devices used to monitor and treat arrhythmias and other heart problems have generally had one of two drawbacks—they are made with rigid materials that can't move to accommodate a ...

Electronics & Semiconductors

Environment-friendly compound shows promise for solar cell use

A widespread transition to solar energy will depend heavily on reliable, safe, and affordable technology like batteries for energy storage and solar cells for energy conversion. At Rensselaer Polytechnic Institute, researchers ...


New concrete possibilities from waste materials

The use of recycled concrete and glass aggregates in concrete production has emerged as a highly promising means of increasing the recycling rate of waste materials—but durability issues have plagued some combinations of ...


Automating materials design

For decades, materials scientists have taken inspiration from the natural world. They'll identify a biological material that has some desirable trait—such as the toughness of bones or conch shells—and reverse-engineer ...

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DNA structure

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.

This text uses material from Wikipedia, licensed under CC BY-SA