Cell division is essential to life, but the mechanism by which emerging daughter cells organize and divvy up their genetic endowments is little understood. In a new study, researchers at the University of Illinois and Columbia University report on how a key motor protein orchestrates chromosome movements at a critical stage of cell division. The study appeared in the Proceedings of the National Academy of Sciences.
Within the complex world of the cell, motor proteins function as a kind of postal service. These proteins carry cargo from one location to another in the cell, a job that requires precision, in both the location and the timing of delivery. They are fueled by a small molecule, adenosine tri-phosphate (ATP).
Some motor proteins are essential to mitosis—the process by which cell division occurs in higher organisms. During cell division it is important for chromosomes to line up at the middle of the parent cell allowing for their separation between the two daughter cells.
Motor proteins play a key role in the movement of chromosomes to and from the poles of the cell. Should any of these processes lose coordination, it could result in disease or cell death.
How chromosomes move during cell division is a question that is fundamental to biology and is of importance in understanding many diseases. University of Illinois physics professor Paul Selvin and his colleagues focused on a motor protein, centromeric protein E (CENP-E) that is known to be associated with chromosomes.
“The question is whether CENP-E acts like a transporter or like an anchor,” Selvin said.
“A transporter moves things around the cell, whereas an anchor sits someplace in the cell, holds onto something, and causes the thing to be held down,” Selvin said. “It turns out CENP-E is known to be an anchor, but is it also a transporter?”
Earlier studies had established a role for CENP-E in aligning paired chromosomes. This alignment is important for ensuring that one of each pair makes its way into a different daughter cell.
Release date: May 13, 2008
Source: University of Illinois at Urbana-Champaign
Filed Under: Genomics/Proteomics