Trojan Horse Ride

When a mimivirus forcibly ejects its genetic material into a cell, it sends along building materials to make a “virus factory”

This is a tale of mimiviruses – giant five-sided viruses – that disguise themselves as bacteria and attack amoebae. This is not science fiction but a true story – one that apparently describes an important stage in the evolution of living cells that contain nuclei.

 

A normal-sized virus penetrates the host cell nucleus, where it infiltrates its genetic material in the form of long, thin molecular strands into the host genome, forcing the host cell to crank out carbon copies of the virus. In contrast, mimiviruses – over ten times the size of normal viruses – don’t bother sneaking into the cell nucleus. Rather, they eject their genetic material through an opening in their structure. This material is compressed into a neat “gift” package – something like a Trojan horse. Alongside, they also unload a pile of building supplies that they use to construct a new “virus factory” inside the cell; they then scavenge cellular materials from around this basic “nucleus,” using them to produce new viruses.

 

Prof. Abraham Minsky of the Faculty of Chemistry investigates how mimiviruses travel, how they get in and out of cells, and how they pack and eject their genetic material. “It may be,” he says, “that such a ‘virus factory’ was a prototype for the cell nucleus, back when cells with nuclei first began to emerge.” In the future, studies on this virus family might point the way to treatments for many types of viral infections, as well as suggesting tools for gene therapy.

 

 

 

 

 

A supermarket cart like that of an itinerant metal collector, filled with assorted items, inhabits the photos in the Crystal Habit series. The cart’s owner – the person who collected the objects – is missing from the images. Computer manipulation of the photo makes the cart appear to have no context, to be divorced from the urban environment in which one would expect to find it. The cart’s isolation, its assorted contents, seem to focus one’s thoughts on the absent collector: Who is he or she? The cart and its contents are thus a three-dimensional sculpture rendered in the two-dimensional medium of photography.