KANSAS CITY, MOResearchers at the Stowers Institute for Medical Research have glimpsed two proteins working together inside living cells to facilitate communication between the cell's nucleus and its exterior compartment, the cytoplasm. The research provides new clues into how a crucial protein that is found in organisms from yeast to humans does its work.
The study, led by Stowers Investigator Sue Jaspersen, Ph.D., focused on a protein called Ndc1, which controls when and where a cell inserts holes into the double-walled membrane that surrounds its nucleus. In yeast, these holes become the sites for two essential structures: passageways called nuclear pore complexes, and spindle pole bodies, which anchor the cytoskeletal filaments that pull chromosomes to opposite sides of a dividing cell.
"Too many or too few insertion sites will have disastrous consequences," Jaspersen says, explaining that new nuclear pore complexes and spindle pole bodies must be created each time a cell prepares to divide to ensure genetic material can be properly distributed and daughter cells are equipped for gene activation and protein production. Her team's findings on Ndc1's interactions with a protein called Mps3, which appears to govern Ndc1's distribution on the nuclear envelope, are described in the February 10, 2014 issue of the Journal of Cell Biology.
Jaspersen and her colleagues set out to study Ndc1 because it is absolutely crucial for cell survival. They knew that in yeast, Ndc1 is embedded in the nuclear envelope and is needed for the insertion of both nuclear pore complexes and spindle pole bodies. But because cells are so sensitive to changes in Ndc1, scientists had been unable to learn much about how the protein functions.
Traditional genetic strategies of eliminating, altering, or increasing Ndc1 to test its function typically killed cells. "Having the exact right amount of Ndc1 is really critical," Jaspersen says. "Tha
|Contact: Gina Kirchweger|
Stowers Institute for Medical Research