MBL, WOODS HOLE, MA There are two ways in which cooperation is the theme of a paper published this week by Mark Alliegro and Mary Anne Alliegro, scientists at the Marine Biological Laboratorys (MBL) Josephine Bay Paul Center.
One is revealed in the papers acknowledgements, where the Alliegros thank those who helped them after Hurricane Katrina completely disrupted their laboratory at Louisiana State University (LSU) in New Orleans and their lives in 2005.
The second is the papers scientific theme: the origin of the centrosome, a component of animal cells that functions in cell division. In their paper, published in Proceedings of the National Academy of Sciences, the Alliegros give evidence that the centrosome evolved through symbiogenesis in which previously independent organisms fuse, become mutually dependent, and over time, become a single composite organism rather than by the evolutionary process of random, heritable mutations and natural selection.
The Alliegros moved to the MBL permanently in September 2007, after two years of attempting to forge on in a devastated New Orleans. We realized, if we stayed there, our research program would not survive, says Mark Alliegro, who was a professor at LSU Health Sciences Center.
The origin of the centrosome, their paper points out, has been controversial for many years. The theory of symbiogenesis as a mechanism of evolution has also stirred debate since it was introduced in the 1920s and subsequently elaborated in the 1960s by Lynn Margulis of University of Massachusetts, Amherst. Today, only two cellular components the mitochondria and the chloroplasts are generally accepted by evolutionary biologists as having a symbiogenetic origin. The Alliegros paper suggests that centrosomes are another likely candidate.
They base their argument on evidence that the centrosomes, which they obtained from the eggs of the surf clam Spisula, contain RNA that is likely a rem
|Contact: Diana Kenney|
Marine Biological Laboratory