( ed into different paths from the starti...)UF scientists reveal ancient origin of vertebrate skeleton

"The lamprey is like the great-, great-, great-aunt descended from the earliest backboned animal," said Michael Miyamoto, Ph.D., a professor and associate chairman of UF's zoology department. "Our question was whether the earliest vertebrates used a collagen recipe or a non-collagen recipe to form their skeletons, and by examining the lamprey, we found a shared recipe. Because of the lamprey, we know it is much more ancient genetic pathway that activates the collagen matrix."

Animal collagen, often associated with the full lips of movie stars, is used for a variety of medical purposes, including reconstructive surgery. But UF Genetics Institute researchers were interested in a material known as type II collagen - the primary structural molecule for jawed vertebrates for at least 500 million years. It is essential in the human body, forming cartilage throughout embryonic skeleton and generally serving as a framework for building bone.

With GuangJun Zhang, Ph.D., a graduate student in zoology, the research team used gene cloning and gene sequencing analysis to demonstrate two type II collagen genes are expressed during the development of the lamprey's cartilaginous skeleton. In addition, they isolated a gene called Sox9, a regulator of collagen gene activity in vertebrates.

The results indicate the collagen-based skeleton evolved before the jawed and jawless vertebrates split into different paths, not afterward. In addition, the research shows that scientists have to dig beyond bone and cartilage to unravel vertebrate relationships, according to Michael Caldwell, Ph.D., an associate professor of earth and atmospheric sciences and of biological sciences at the University of Alberta.

"One of the classic characters in the scientific literature for the past 100 years that has been argued to link all vertebrates, to the exclusion of lampr
'"/>

Source:University of Florida