UTHSC Associate Professor David R. Nelson and Colleagues Find Genes Central to Vertebrate Biology
Memphis, Tenn. (April 18, 2013) – How did vertebrate animals make their way from the primordial ocean to traversing land? That’s no small question.
Through their work finding and studying genes that are central to vertebrate biology, a University of Tennessee Health Science Center (UTHSC)
researcher and his colleagues have taken another step toward solving this massive scientific riddle. Their research paper titled, “The African
coelacanth genome provides insights into tetrapod evolution,” appears as the cover story in the April 18 edition of Nature, the international weekly
journal of science.
The African coelacanth (Latimeria chalumnae) is a lobe-finned, fish that was thought to have become extinct 70 million years ago, until living
specimens were discovered in 1938. Adult versions of the heavily boned, oftentimes slimy fish measure about 72 inches in length and can weigh more than
David R. Nelson, PhD, associate professor in the UTHSC Department of Microbiology, Immunology and Biochemistry, worked with John Stegeman, PhD, Senior
Scientist, and Jed Goldstone, PhD, Research Specialist, both at The Woods Hole Oceanographic Institute in Massachusetts, to find and annotate the
cytochrome P450 genes in the coelacanth.
“Since this is a slowly evolving creature, the gene set of P450s is a representation of this family of genes at the time of land colonization about 370
million years ago,” Dr. Nelson said. “It is the starting point for the evolution of all P450 genes in land animals including humans. These genes
metabolize drugs and foreign chemicals that get into our bodies from the food we eat, the air we breathe and anything absorbed through our skin. They
also synthesize or modify many important small molecules such as steroids, cholesterol, retinoic acid, prostaglandins and other eicosanoids and fatty
acids. They are very important genes for vertebrate biology.”
He noted, “The significance of this paper is the key position of the coelacanth as a present-day relative of the first primitive animal to crawl out
onto the land. By sequencing the genome of the coelacanth, we can see what has been newly evolved for life on the land, such as genes for lungs,
olfaction (smell), nitrogenous waste elimination (urea instead of ammonia), hearing, immunity, etc. We can also see what has been lost as we moved out
of a water environment to a land environment. On land there are no more requirements for fins, gas bladders for buoyancy, etc.”
To read the article in Nature, visit: http://www.nature.com/nature/journal/v496/n7445/full/nature12027.html?WT.ec_id=NATURE-20130418.
As Tennessee’s only public, statewide academic health system, the mission of the University of Tennessee Health Science Center (UTHSC) is to bring the
benefits of the health sciences to the achievement and maintenance of human health, with a focus on the citizens of Tennessee and the region, by
pursuing an integrated program of education, research, clinical care, and public service. Offering a broad range of postgraduate and selected
baccalaureate training opportunities, the main UTHSC campus is located in Memphis and includes six colleges: Allied Health Sciences, Dentistry,
Graduate Health Sciences, Medicine, Nursing and Pharmacy. UTHSC also educates and trains cohorts of medicine, pharmacy and/or allied health students –
in addition to medical residents and fellows — at its major sites in Knoxville, Chattanooga and Nashville. Founded in 1911, during its more than 100
years, UT Health Science Center has educated and trained more than 53,000 health care professionals in academic settings and health care facilities
across the state. For more information, visit www.uthsc.edu.