Featured Research

from universities, journals, and other organizations

DNA analysis aids in classifying single-celled algae

Date:
September 20, 2012
Source:
Penn State
Summary:
For nearly 260 years -- since Carl Linnaeus developed his system of naming plants and animals -- researchers classified species based on visual attributes like color, shape and size. In the past few decades, researchers found that sequencing DNA can more accurately identify species. A group of single-celled algae -- Symbiodinum -- that live inside corals and are critical to their survival -- are only now being separated into species using DNA analysis, according to biologists.

Corals are able to build large reef structures in many of the worlds shallow tropical environments because they contain symbiotic micro-algae called Symbiodinium (and often referred to as zooxanthellae). Distinct symbiont species which are found in different corals look nearly identical.
Credit: Todd C LaJeunesse

For nearly 260 years -- since Carl Linnaeus developed his system of naming plants and animals -- researchers classified species based on visual attributes like color, shape and size. In the past few decades, researchers found that sequencing DNA can more accurately identify species. A group of single-celled algae -- Symbiodinium -- that live inside corals and are critical to their survival -- are only now being separated into species using DNA analysis, according to biologists.

"Unfortunately with Symbiodinium, scientists have been hindered by a traditional morphology-based system of species identification that doesn't work because these organisms all pretty much look the same -- small round brown cells," said Todd LaJeunesse, assistant professor of biology at Penn State. "This delay in adopting the more accurate convention of identifying species using genetic techniques has greatly impeded progress in the research of symbiotic reef-building corals, especially with regard to their ability to withstand global warming."

LaJeunesse and his colleagues looked at Symbiodinium that previously had been grouped together as subsets of the same species. They report their results in the September issue of the Journal of Phycology. They examined specific DNA markers -- identifiers -- from the organisms cell nuclei, mitochondria and chloroplasts. Even though the symbionts appeared very much the same, except for their size, genetic evidence confirmed that the two are different species altogether.

These findings indicate that hundreds of other coral symbionts already identified with preliminarily genetic data are also distinct species with unique ecological distributions.

"The recognition of symbiont species diversity should substantially improve research into reef-building corals and facilitate breakthroughs in our understanding of their complex biology," said LaJeunesse.

He began his work of classifying Symbiodinium using genetic techniques as part of his research into their ecology and evolution and in later studies of coral bleaching events related to global warming.

"Knowing exactly which Symbiodinium species you're dealing with is important because certain species of Symbiodinium associate with certain species of coral," he said. "Although many corals are dying as a result of global climate change, some may be able to survive because they associate with Symbiodinium species that are better adapted to warm water temperatures."

Other researchers on this project were John Everett Parkinson, graduate student in biology, Penn State, and James Davis Reimer, associate professor of biology, University of the Ryukyus, Okinawa.

The National Science Foundation supported this research.


Story Source:

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


Cite This Page:

Penn State. "DNA analysis aids in classifying single-celled algae." ScienceDaily. ScienceDaily, 20 September 2012. <www.sciencedaily.com/releases/2012/09/120920120557.htm>.
Penn State. (2012, September 20). DNA analysis aids in classifying single-celled algae. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2012/09/120920120557.htm
Penn State. "DNA analysis aids in classifying single-celled algae." ScienceDaily. www.sciencedaily.com/releases/2012/09/120920120557.htm (accessed September 17, 2014).

Share This



More Plants & Animals News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 Video provided by AFP
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