Posted on 10/18/2009 1:01:12 AM PDT by neverdem
Role of a crucial protein helps answer why the cell’s transportation hub looks like a stack of pancakes
Researchers have pinpointed a protein that keeps the trains running through the cell’s Grand Central station.
The protein works in tandem with other molecules to pull membrane packets off the surface of a cell’s Golgi apparatus, giving the crucial organelle its distinctive flattened shape.
“It’s a nice simple mechanism for how the shape of something is a consequence of its function,” says Seth Field of the University of California, San Diego and a coauthor of the study, which appears in the Oct. 16 Cell. “It’s a lot simpler than people would have guessed.”
The Golgi apparatus is the staging area for all proteins whose final destinations lie outside the cell, including hormones, antibodies and components of hair, bone and skin. Everything that is needed elsewhere in the body goes through the Golgi to get packaged and prepared for its journey. The proteins leave the Golgi wrapped in vesicles, bubbles of the organelle’s membrane.
The function of the Golgi apparatus is well known, but its odd shape has long been a mystery. Researchers have described it as a stack of pancakes or a pile of deflated balloons. The pancakes are membranes that enclose empty space that proteins travel through.
“No one had understood why the Golgi looks like that, what purpose that serves,” Field says.
Now Field and his colleagues have pinpointed the protein responsible. In an analysis of the binding properties of 4,000 fruit-fly proteins, one called GOLPH3 latched onto another molecule that was known to be important to the Golgi’s function.
Further scans found that a motor protein like those found in muscles also piggybacked on GOLPH3. The researchers found that if any one of these three molecules — GOLPH3, the...
(Excerpt) Read more at sciencenews.org ...
Very intelligent design, to say the least.
ping
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.