New Study Reveals Structures of Important Plant Viruses

Flexible filamentous viruses are one of the most destructive groups of plant viruses known. Members of the group include the potato virus X, the citrus leaf blotch virus, the soybean mosaic virus and apple stem pitting virus. The 300-plus species of filamentous viruses are responsible for more than half the viral damage to crop plants throughout the world. But compared to other viruses, very little is known about their structures.

A study, published in the current issue of the journal of Virology, reveals new details on the structures of the important virus group. Viruses are much too small to see with an optical microscope. So the scientists, from six U.S. research institutions, had to use a combination of imaging techniques — x-ray diffraction, cryo-electron microscopy and scanning transmission electron microscopy — in order to elucidate the viral structures. The scientists found out that all flexible filamentous plant viruses share common structures: a common coat protein fold and a ’spiral’ symmetry featuring nine molecular subunits per helical turn.

The structural information that the researchers have obtained may allow scientists to engineer molecules that can interfere with the viruses’ ability to infect plants. Another possible application would be to use modified viruses to introduce genes that instruct plants to make other useful products — such as antibiotics or other drugs.

Read the full article at http://www.vanderbilt.edu/exploration/stories/filamentous.html Subscribers can download the paper published by the Journal of Virology at http://jvi.asm.org/cgi/content/abstract/82/19/9546