Profile of Martin Chalfie
- Tinsley Davis, Freelance Science Writer
Despite having a bad reputation, cholesterol is an essential component of the plasma membranes of animal cells, where it is thought to modulate the properties of the lipid bilayer. Cholesterol can also bind directly to proteins in the membrane. In his Inaugural Article published in 2006, Martin Chalfie, the William R. Kenan, Jr., Professor of Biological Sciences at Columbia University (New York), in collaboration with Thomas Benzing (University of Cologne, Germany), identified a new class of cholesterol-binding proteins among the prohibitin (PHB)-domain protein family (1). PHB-domain proteins appear to regulate a variety of membrane functions, from cell signaling to mechanosensation. Studying two members of the family, MEC-2 and Podocin, Chalfie, Benzing, and their colleagues found that cholesterol is crucial for the activity of two different classes of channel proteins to which the PHB-domain proteins bind. They suggest that the binding of cholesterol by the PHB-proteins alters the local lipid environment of associated membrane proteins and changes their activity.
Questioning Research
Chalfie, born in 1947 and elected to the National Academy of Sciences in 2004, grew up in Chicago. As a child, all elements of science interested him, but he feels his early activities were somewhat mundane. “Unfortunately, I did not have that real indicator of a career in science that many of my friends have. I did not make explosives and almost destroy my home,” he says. As a child, he cut out newspaper comics about nature for a scrapbook and, in high school, participated in a weekly science club after school. “I was fairly good at science in school,” he recalls. “That was the positive reinforcement to keep me going.” Chalfie entered Harvard University (Cambridge, MA) in 1965 and thought that he would major in math. He soon switched gears. “I was attracted to biochemistry because I could do a little …
