Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NC State Geneticists Show Ripple Effects of Gene Mutations

09.09.2003


When a plane arrives late to an airport, it affects more than just the frustrated passengers on the tardy plane – the ripple effects could throw the entire day’s timetable off schedule.



Similarly, in a new study, North Carolina State University geneticists have found that changes to genes regulating olfactory behavior in the fruit fly Drosophila melanogaster, a popular insect model for genetics, have far greater implications than previously appreciated.

The study is presented in a paper published in the Sept. 7 online edition of Nature Genetics.


Dr. Robert Anholt, professor of zoology and genetics, director of NC State’s Keck Center for Behavioral Biology and the paper’s lead author, said that in the study of how genes affect behavior, the days of thinking about genes in a linear fashion are over.

“In the past, scientists would make a mutation – or a change in the genetic information – in a gene, observe the effect on behavior and say that the particular gene is essential for a particular behavior,” he said. “But when you perturb a gene, you do not just perturb a gene. You create, instead, an effect like the ripples produced when you throw a pebble into a pond. We need to think in terms of networks that generate behavior.”

The study breaks new ground because it enabled the scientists to quantify the extent of the ripples in the genome that affect behavior, Anholt said.

In previous studies, the scientists introduced little pieces of DNA, or transposons, randomly into the genome. “If the transposons insert in a regulatory region of a gene, or inside a gene, they disrupt the function of the gene,” Anholt said.

Anholt’s lab studied olfactory behavior because it can be readily measured and is essential for survival. The investigators isolated a series of smell-impaired flies that were genetically identical but with one particular disrupted gene, and showed enhanced effects when these genes interacted.

“We were able to place them into a network of genetic interactions which provided us with a little view of how genes might work together to determine behavior. Imagine that you are putting together pieces of a puzzle and there comes a moment when you get an inkling of what the final picture might look like,” Anholt said.

In the study published in Nature Genetics, the scientists took five genes involved in olfactory behavior in Drosophila melanogaster, extracted the RNA from these five lines and compared their transcriptomes, or all the RNA, of males and females separately. It was important for this study to use a model organism that can be highly inbred so that all individuals are genetically identical. Equally important was the use of sophisticated statistical analyses applied by study co-author Dr. Trudy Mackay, William Neal Reynolds professor of genetics at NC State.

“If we make a perturbation in one gene by introducing a transposon, what happens to the rest of the transcriptome? That’s the question we asked,” Anholt said. “It turns out that the genomic perturbations arising from a single insertion are substantial. With this experiment, we could see how many genes were perturbed when we mutated one gene, but we could also look at the overlap of the ripples.”

In addition, the researchers were able to identify the numbers of male- or female-specific genes that were affected.

Finally, in what Anholt called the “tour de force” of the study, the researchers attempted to find whether genes in the ripples actually affect olfactory behavior.

To address the issue, the researchers went to the Drosophila stock center and its collection of mutants and used a genetic method, pioneered by Mackay, called quantitative complementation tests.

“Two-thirds of the genes within ripples resulting from the smell-impaired mutations themselves affected olfactory behavior. This means that the interactions that we see in the transcriptome mirror the genetic interactions that we see at the behavioral level. It also shows that this approach is a very good strategy for large-scale gene discovery for behavior.”

Anholt says this approach can be applied to any complex trait in any animal with a controlled genetic background.

“In the end, we’re trying to find how subtle variations in genes affect behavior, and how genetic networks change in response to the environment and during development and evolution,” he said.

The study was done in collaboration with Syngenta’s Torrey Mesa Research Institute, and the W.M. Keck Foundation and the National Institutes of Health supported the research.

Mick Kulikowski | NC State University
Further information:
http://www.ncsu.edu/news/press_releases/03_09/244.htm

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>