Featured Research

from universities, journals, and other organizations

Genomic archeology reveals early evolution of sex chromosomes

Date:
May 17, 2011
Source:
American Society for Microbiology
Summary:
A team from Sweden is using genomics to shed light on the early evolutionary history of sex chromosomes. Among other things, the genome is a place where the distant past can be investigated. Researchers have used it most notably to trace the relationships among species far more accurately than can be done with conventional methods.

A team from Uppsala University, Uppsala, Sweden, is using genomics to shed light on the early evolutionary history of sex chromosomes. The research is published in the April 2011 Eukaryotic Cell.

Among other things, the genome is a place where the distant past can be investigated. Researchers have used it most notably to trace the relationships among species far more accurately than can be done with conventional methods.

Sex chromosomes in animals are so ancient -- in the hundreds of millions of years old--that they retain few traces of the historical events that drove their evolution. But the researchers had found in earlier studies that the mating type chromosomes in the self-fertilizing fungus, Neurospora tetrasperma, which are analogous to X and Y in sexually reproducing organisms, have a region of suppressed recombination that is roughly as recent as the split between chimpanzees and hominins -- less than six million years old.

Suppressed recombination preserves the genomic landscape, because normally, chromosomes recombine during mating, which shuffles the genes like a deck of cards. But suppressed recombination also interferes with natural selection, by forcing genes to be selected or deselected in packages, like the packages of options on new cars that force you to buy the navigation system, the satellite radio, and the MP3 system if you want the side curtain airbags.

The Uppsala researchers' major discovery is that many preferred codons disappeared from regions of the mating type chromosomes where recombination was suppressed. Codons are the "words" of the genetic code. Different codons code for each of the 20 amino acids used in living systems. They code for amino acids, which are the building blocks of proteins, the molecules that form both most of the structure, and most of the machinery cells. Like words in human language, codons often have synonyms. But "Many organisms studied to date preferentially use a specific set of preferred codons which are believed to promote efficient and accurate protein synthesis," says corresponding author Hanna Johannesson. Thus, they are known as "preferred codons."

The suppressed recombination the researchers had found earlier in N. tetrasperma is accompanied by the loss of these preferred codons.

Beyond this, "Our study furthers the understanding of factors driving mutational changes in genomes, which is a key issue in medical and natural science," says Johannesson. "For example, the onset of mutations, and the ability, or inability of organisms to eliminate them from their genome underlie key processes such as the onset of diseases in animals, and the rate of species extinctions. Our study advances the understanding of when and how young regions of suppressed recombination in sex regulating chromosomes accumulate mutations, and why evolution may fail to remove these harmful changes in an efficient manner."


Story Source:

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


Journal Reference:

  1. C. A. Whittle, Y. Sun, H. Johannesson. Degeneration in Codon Usage within the Region of Suppressed Recombination in the Mating-Type Chromosomes of Neurospora tetrasperma. Eukaryotic Cell, 2011; 10 (4): 594 DOI: 10.1128/EC.00284-10

Cite This Page:

American Society for Microbiology. "Genomic archeology reveals early evolution of sex chromosomes." ScienceDaily. ScienceDaily, 17 May 2011. <www.sciencedaily.com/releases/2011/05/110516175302.htm>.
American Society for Microbiology. (2011, May 17). Genomic archeology reveals early evolution of sex chromosomes. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2011/05/110516175302.htm
American Society for Microbiology. "Genomic archeology reveals early evolution of sex chromosomes." ScienceDaily. www.sciencedaily.com/releases/2011/05/110516175302.htm (accessed August 21, 2014).

Share This




More Plants & Animals News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Possible Ebola Patient in Isolation at California Hospital

Possible Ebola Patient in Isolation at California Hospital

Reuters - US Online Video (Aug. 20, 2014) — A patient who may have been exposed to the Ebola virus is in isolation at the Kaiser Permanente South Sacramento Medical Center. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) — Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Unsustainable Elephant Poaching Killed 100K In 3 Years

Unsustainable Elephant Poaching Killed 100K In 3 Years

Newsy (Aug. 20, 2014) — Poachers have killed 100,000 elephants between 2010 and 2012, as the booming ivory trade takes its toll on the animals in Africa. Video provided by Newsy
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) — Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. 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