Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCSD Study Shows ’Junk’ DNA Has Evolutionary Importance

20.10.2005


Genetic material derisively called “junk” DNA because it does not contain the instructions for protein-coding genes and appears to have little or no function is actually critically important to an organism’s evolutionary survival, according to a study conducted by a biologist at UCSD.


Fruit fly Drosophila melanogaster. Credit: UCSD



In the October 20 issue of Nature, Peter Andolfatto, an assistant professor of biology at UCSD, shows that these non-coding regions play an important role in maintaining an organism’s genetic integrity. In his study of the genes from the fruit fly Drosophila melanogaster, he discovered that these regions are strongly affected by natural selection, the evolutionary process that preferentially leads to the survival of organisms and genes best adapted to the environment.

Andolfatto’s findings are important because the similarity of genome sequences in fruit flies, worms and humans suggest that similar processes are probably responsible for the differences between humans and their close evolutionary relatives.


“Sequencing of the complete genome in humans, fruit flies, nematodes and plants has revealed that the number of protein-coding genes is much more similar among these species than expected,” he says. “Curiously, the largest differences between major species groups appear to be the amount of ‘junk’ DNA rather than the number of genes.”

Using a recently developed population genetic approach, Andolfatto showed in his study that these expansive regions of “junk” DNA—which in Drosophila accounts for about 80 percent of the fly’s total genome—are evolving more slowly than expected due to natural selection pressures on the non-protein-coding DNA to remain the same over time.

“This pattern most likely reflects resistance to the incorporation of new mutations,” he says. “In fact, 40 to 70 percent of new mutations that arise in non-coding DNA fail to be incorporated by this species, which suggests that these non-protein-coding regions are not ‘junk,’ but are somehow functionally important to the organism.”

Andolfatto also found that “junk” regions exhibit an unusually large amount of functional genetic divergence between different species of Drosophila, further evidence that these regions are evolutionarily important to organisms. This implies that, like evolutionary changes to proteins, changes to these “junk” parts of the genome also play an important role in the evolution of new species.

“Protein evolution has traditionally been emphasized as a key facet of genome evolution and the evolution of new species,” says Andolfatto. “The degree of protein sequence similarity between humans and chimpanzees, and other closely-related but morphologically distinct taxa, has prompted several researchers to speculate that most adaptive differences between taxa are due to changes in gene regulation and not protein evolution. My results lend support to this view by demonstrating that regulatory changes have been of great importance in the evolution of new Drosophila species.”

Comment: Peter Andolfatto (858) 334-8039

Media Contact: Kim McDonald (858) 534-7572

Kim McDonald | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Life Sciences:

nachricht Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover

nachricht First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>