Featured Research

from universities, journals, and other organizations

Scientists unlock evolutionary secret of blood vessels

Date:
February 21, 2012
Source:
Scripps Research Institute
Summary:
Scientists have shed light on how vertebrates evolved closed circulation systems designed to more effectively carry blood to organs and tissues.

The ability to form closed systems of blood vessels is one of the hallmarks of vertebrate development. Without it, humans would be closer to invertebrates (think mollusks) in design, where blood simply washes through an open system to nourish internal organs. But vertebrates evolved closed circulation systems designed to more effectively carry blood to organs and tissues.

Precisely how that happened has remained a clouded issue. But now, a team of scientists from the California and Florida campuses of The Scripps Research Institute have shed light on the topic in a study published February 21, 2012, in the journal Nature Communications.

The process of building a closed circulation system is complicated biologically and, from an evolutionary perspective, time-consuming -- involving billions of years. During this lengthy process, new domains (parts of a protein that can evolve and function independently of each other) have been added progressively to key molecules.

The scientists focused on one specific domain known as UNE-S. UNE-S is part of SerRS, a type of tRNA synthetase in species with closed circulatory systems; tRNA synthesases are enzymes that help charge tRNA with the right amino acid to correctly translate genetic information from DNA to proteins.

The scientists found that UNE-S is essential for proper development of an embryo, containing a specific sequence or "nuclear localization signal" that directs SerRS to the cell nucleus. There, it affects the expression of a key regulator of new blood vessel growth.

"I think a lot happened during this evolutionary transition to a closed system and the appearance of this domain on this specific synthetase is one of them," said Xiang-Lei Yang, a Scripps Research associate professor who led the collaborative study. "Because this synthetase plays such an essential role in vascular development, it must have had a role in the transition to a closed system."

To help elucidate the role of UNE-S, the researchers turned to zebrafish as a model organism. Shuji Kishi, an assistant professor on the Scripps Florida campus who worked on the new study, noted that zebrafish have emerged over the past decade as a powerful system to study both aging and development. "Zebrafish offer a number of advantages for study because embryonic development is external to the mother and the embryos are transparent, making them an ideal model for developmental biology," he said.

To find clues to SerRS function, the team examined SerRS mutants, which are linked to abnormal blood vessel formation and defective blood circulation. In their experiments, the scientists used a variety of techniques, including crystal structure, biochemical analysis, and cell biology experiments.

Interestingly, the findings show that SerRS mutants often delete the nuclear signal or keep it hidden in an alternative conformation -- like locking someone in a closet under an assumed name -- rendering it ineffective. "We were astonished by what we found," said Yang. "Sequestering is a very interesting property."

The scientists were able to design a second mutation to release the sequestered nuclear signal and to restored normal blood vessel development.

In addition to suggesting that acquisition of UNE-S has a role in the establishment of the closed circulatory systems of vertebrates, these results are the first to show an essential role for a tRNA synthetase-associated appended domain for an organism.

The first authors of the study, "Unique Domain Appended to Vertebrate Trna Synthetase is Essential For Vascular Development," are Xiaoling Xu and Yi Shi of Scripps Research. Other authors include Hui-Min Zhang of Florida State University, Eric C. Swindell of The University of Texas Medical School at Houston, Alan G. Marshall of Florida State University, and Min Guo of Scripps Research.

The study was supported by grants from the National Institutes of Health, the Skaggs Foundation, the State of Florida, and the National Foundation for Cancer Research.


Story Source:

The above story is based on materials provided by Scripps Research Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. Xiaoling Xu, Yi Shi, Hui-Min Zhang, Eric C. Swindell, Alan G. Marshall, Min Guo, Shuji Kishi, Xiang-Lei Yang. Unique domain appended to vertebrate tRNA synthetase is essential for vascular development. Nature Communications, 2012; 3: 681 DOI: 10.1038/ncomms1686

Cite This Page:

Scripps Research Institute. "Scientists unlock evolutionary secret of blood vessels." ScienceDaily. ScienceDaily, 21 February 2012. <www.sciencedaily.com/releases/2012/02/120221124810.htm>.
Scripps Research Institute. (2012, February 21). Scientists unlock evolutionary secret of blood vessels. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/2012/02/120221124810.htm
Scripps Research Institute. "Scientists unlock evolutionary secret of blood vessels." ScienceDaily. www.sciencedaily.com/releases/2012/02/120221124810.htm (accessed August 30, 2014).

Share This




More Plants & Animals News

Saturday, August 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Raw: Australian Sheep Gets Long Overdue Haircut

Raw: Australian Sheep Gets Long Overdue Haircut

AP (Aug. 28, 2014) Hoping to break the record for world's wooliest, Shaun the sheep came up 10 pounds shy with his fleece weighing over 50 pounds after being shorn for the first time in years. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Minds Blown: Scientists Develop Fish That Walk On Land

Minds Blown: Scientists Develop Fish That Walk On Land

Newsy (Aug. 28, 2014) Canadian scientists looking into the very first land animals took a fish out of water and forced it to walk. Video provided by Newsy
Powered by NewsLook.com
Huge Ancient Wine Cellar Found In Israel

Huge Ancient Wine Cellar Found In Israel

Newsy (Aug. 28, 2014) An international team uncovered a large ancient wine celler that likely belonged to a Cannonite ruler. 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:
from the past week

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