PROVIDENCE, R.I. [Brown University] As they work together to form body parts, cells in developing organisms communicate like workers at a construction site. The discovery of a new signaling molecule in flies by Brown University biologists not only helps explain how cells send many long-haul messages, but also provides new clues for researchers who study how human development goes awry, for instance in cases of cleft lip and palate.
For all the diversity of life, animal cells employ only a small set of proteins to send those jobsite signals that coordinate construction. For that reason, said Kristi Wharton, associate professor of molecular biology, cell biology and biochemistry, studying these proteins and pathways in fruit flies can allow biologists and physicians to explain how development and other cellular processes occur in a wide variety of creatures and tissues.
"We are interested in how the pattern of a hand forms or how the pattern of a wing forms," Wharton said. "How do cells know their position in a developing tissue?"
In humans a key family of the signaling molecules that convey such messages are bone morphogenic proteins (BMPs). In fruit flies the directly analagous proteins carry the name "glass-bottom boat" (Gbb), because a mutant form makes larvae appear clear instead of milky white. To date, the conventional wisdom has been that signaling comes from a fly form of BMP known as Gbb15.
"The thought for the longest time is that this smaller protein is the only product that is formed and important for signaling," Wharton said. "But we found another form of this signaling molecule that was not previously known."
Wharton and former postdoctoral fellow Takuya Akiyama introduce the new molecule, Gbb38, in the April 3 edition of the journal Science Signaling. Experiments showed that in tissues where it was abundant, particularly parts of the wing, Gbb38 proved responsible for more signaling activity tha
|Contact: David Orenstein|