Featured Research

from universities, journals, and other organizations

Fluid equilibrium in prehistoric organisms sheds light on a turning point in evolution

Date:
September 24, 2011
Source:
American Physiological Society
Summary:
Maintaining fluid balance in the body is essential to survival. By researching recent genomic data, researchers have found genetic evidence that links this intricate process to a turning point in evolution.

Maintaining fluid balance in the body is essential to survival, from the tiniest protozoa to the mightiest of mammals. By researching recent genomic data, Swiss researchers have found genetic evidence that links this intricate process to a turning point in evolution.

The study was led by Bernard Rossier, Professor Emeritus, University of Lausanne, along with colleagues Romain A. Studer, Emilie Person, and Marc Robinson-Rechavi. Dr. Rossier will discuss the team's findings at the 7th International Symposium on Aldosterone and the ENaC/Degenerin Family of Ion Channels, sponsored by the American Physiological Society. Dr. Rossier's presentation, "Evolution of ENaC and Na-K-ATPase as Limiting Factors of Aldosterone Action," is based in part on the team's recent article published in the journal Physiological Genomics.

Timing Is Everything

In humans, the hormone aldosterone affects fluid balance by controlling the epithelial sodium channel (ENaC), a protein that traverses a cell's membrane and facilitates the movement of salt into and out of the cell. By searching for genes that descended from a common ancestral DNA sequence (homologs), the researchers found that the emergence of ENaC and Na, K-ATPase (sodium pump), an enzyme that also plays a role in sodium transport, coincided with the emergence of multi-celled organisms.

Dr. Rossier and his team focused their analysis on eukaryotes -- organisms whose cells contain complex structures within enclosed membranes -- and sought to determine when and where on the eukaryotic family tree ENaC first appeared. When tracing the alpha, beta, and gamma subunits of ENaC back, the team found that the beta subunit appeared slightly before the emergence of Metazoans (multicellular animals with differentiated tissues) roughly 750 million years ago.

"The alpha subunit is an old protein found everywhere, in any kind of organism, but the beta and gamma subunits appear much later in evolution," said Dr. Rossier. "The appearance of the beta subunit is particularly significant because it is required for the function of the sodium pump. Without it, a functional sodium pump cannot be expressed at the cell surface. What is interesting is that it appeared right before the dividing point between unicellular organisms and multicellular organisms."

The team also found homologs of ENaC in a single-celled organism, the Naegleria gruberi. Although N. gruberi is a eukaryote and shares a common ancestor with Metazoans, it is located on a different branch of the eukaryotic family tree, among the Excavates. At first glance it might make sense to assume that both Metazoans and Excavates got their ENaC from their common eukaryotic ancestor, but ENaC is absent in all other branches of the eukaryotic tree.

Dr. Rossier said that although it is possible that the genes for ENaC originated in the common ancestor of eukaryotes and were lost in all branches except the Metazoa and the Excavates, there is another possibility. There could have been a lateral transfer of genes between N. gruberi and a Metazoan ancestor, one that lived between the last common ancestor of all eukaryotes and the first Metazoans.

Whether a Metazoan transferred the genes for ENaC to N. gruberi or the other way around, Dr. Rossier is not sure. Either way, the fact that ENaC gene family appeared just before the emergence of Metazoans suggests it is somehow linked to the development of multi-celled organisms, he said.


Story Source:

The above story is based on materials provided by American Physiological Society. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. A. Studer, E. Person, M. Robinson-Rechavi, B. C. Rossier. Evolution of the epithelial sodium channel and the sodium pump as limiting factors of aldosterone action on sodium transport. Physiological Genomics, 2011; 43 (13): 844 DOI: 10.1152/physiolgenomics.00002.2011

Cite This Page:

American Physiological Society. "Fluid equilibrium in prehistoric organisms sheds light on a turning point in evolution." ScienceDaily. ScienceDaily, 24 September 2011. <www.sciencedaily.com/releases/2011/09/110922134531.htm>.
American Physiological Society. (2011, September 24). Fluid equilibrium in prehistoric organisms sheds light on a turning point in evolution. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2011/09/110922134531.htm
American Physiological Society. "Fluid equilibrium in prehistoric organisms sheds light on a turning point in evolution." ScienceDaily. www.sciencedaily.com/releases/2011/09/110922134531.htm (accessed October 22, 2014).

Share This



More Fossils & Ruins News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Sunken WWII U-Boat That Fired On U.S. Convoy Found

Sunken WWII U-Boat That Fired On U.S. Convoy Found

Newsy (Oct. 22, 2014) U-576, a long-lost German U-boat the U.S. sank in 1942, has been found just 30 miles off North Carolina's coast and near the wreckage of another ship. Video provided by Newsy
Powered by NewsLook.com
Turns Out Jack The Ripper's True Identity Is Still Unknown

Turns Out Jack The Ripper's True Identity Is Still Unknown

Newsy (Oct. 20, 2014) After testing DNA from a shawl found near one of Jack the Ripper's victims, a scientist said he'd identified the killer. New reports refute the claim. Video provided by Newsy
Powered by NewsLook.com
Fish Fossil Shows First-Ever Sex Was Done Side By Side

Fish Fossil Shows First-Ever Sex Was Done Side By Side

Newsy (Oct. 19, 2014) A 380-million-year-old fish may be the first creature to have copulative sex - and it was side by side with arms linked, like square dancers. Video provided by Newsy
Powered by NewsLook.com
As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

Newsy (Oct. 19, 2014) With Sweden on the look-out for a suspected Russian sub, a lot of people are talking about the Cold War, but is it an apt comparison? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins