A study on genetic variation authored by biologists at New York University and the Albert Einstein College of Medicine has been cited as one of the 15 evolutionary gems by Nature magazine. The publication selected 15 studies published by Nature over the past decade that illustrate the breadth, depth, and power of evolutionary thinking as part of its celebration of the 200th birthday of Charles Darwin, who was born on Feb. 12, 1809.
The study, authored by NYUs Mark Siegal, an assistant professor and part of NYUs Center for Genomics and Systems Biology, and Aviv Bergman, a professor at the Albert Einstein College of Medicine, explores a component of evolutionary capacitance-that is, do species who remain mostly unchanged for millions of years, then change dramatically and suddenly, store the potential for these sudden alterations, unleashing a flood of otherwise hidden variation at times of environmental stress?
Early research modeled evolutionary capacitance by showing, with experiments on fruit flies, that key proteins involved in the regulation of developmental processes are chaperoned by a protein called Hsp90. Hsp90 is produced more at times of stress. On occasion, Hsp90 is overwhelmed by other processes and the proteins it normally regulates are left to run free, producing a welter of otherwise hidden variation.
In their study, published in 2003, Siegal and Bergman explored whether evolutionary capacitance is particular to Hsp90 or, rather, found more generally. They used numerical simulations of complex gene networks and genome-wide expression data from yeast strains in which single genes had been deleted. They showed that most, and perhaps all, genes hold variation in reserve that is released only when they are functionally compromised. Their findings suggested that evolutionary capacitance goes wider and deeper than a single protein.