A Florida State University researcher has identified the important role that a key protein plays in cell division, and that discovery could lead to a greater understanding of stem cells.
Timothy L. Megraw, an associate professor in the College of Medicine, has outlined his findings in the cover story of the June 15 issue of Developmental Cell. The article, "CDK5RAP2 Regulates Centriole Engagement and Cohesion in Mice," was co-authored by researchers from the University of Texas Southwestern Medical Center at Dallas and the University of North Texas.
In August, Megraw received a four-year, $1.2 million grant from the National Institutes of Health to explore the role of centrosomes and cilia in cell division and their connections to human disease.
One long-term goal of Megraw's research has been to discover which parts of the cell play which roles in cell division. The centrosome is an important player. When a cell is ready to divide, it typically has two centrosomes, each containing a "mother and daughter" pair of centrioles tightly connected to each other, or "engaged."
"Two is important," Megraw said, "because you divide your genetic material into two equal sets. Each of these centriole pairs organizes the cytoskeletal machinery that pulls the chromosomes apart. So you don't want there to be more than two, because then you run the risk of unequal separation of the chromosomes."
The centrioles are supposed to replicate only once during the cell cycle. What keeps them from replicating more often was discovered a few years ago, Megraw said, when researchers identified mother-daughter engagement as the key. Once those two become disengaged, it acts as the "licensing" step, in effect giving the centrioles permission to replicate.
Unknown until now, Megraw said, was what regulated those centrioles to remain engaged until the proper time, to prevent excess replication. He suspected that the protein C
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Florida State University