Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Divergent life history shapes gene expression in brains of salmon

20.07.2005


Roughly 15 percent of genes are expressed differently among males of same species



Scientists working with salmon have found that gene expression in the brain can differ significantly among members of a species with different life histories. Their study indicates that roughly 15 percent of Atlantic salmon genes show differential expression in males who migrate from their freshwater birthplaces to mature in oceans versus those who do not leave the freshwater environment to mature.

The researchers, at Harvard University, the University of Massachusetts and the US Geological Survey, report the finding in the current issue of Proceedings of the Royal Society B. They compared female salmon, male salmon that will eventually undertake the well-known journey from their river birthplaces to oceans –- and then migrate heroically back upstream one to three years later to spawn –- and males of the same age known as "sneakers" that mature at greatly reduced size without leaving freshwater.


"The finding that hundreds of the nearly 3,000 genes we studied were expressed differently in the brains of sneakers and other male salmon came as a surprise," says Nadia Aubin-Horth, a postdoctoral researcher in the Bauer Center for Genomics Research in Harvard’s Faculty of Arts and Sciences. "Since these males of the same species in the same wild environment differed only in their life history, we did not expect the expression of so many of their genes to differ."

Aubin-Horth and her colleagues were also surprised by some of the 17 separate classes of genes demonstrating differing activity levels.

"It makes sense that growth genes are suppressed in sneakers and genes associated with reproduction are expressed more, since these fish essentially trade bodily size for faster reproductive maturity," she says. "However, it was unexpected, for instance, that genes associated with learning and memory would be expressed at higher levels in the brains of sneakers. It’s not yet clear why disparities like this would arise."

Aubin-Horth says it is impossible to tell as of yet whether the changes in gene expression are a cause or effect of the various physiological differences between sneakers and other salmon. Their work suggests that the "default" life cycle, in which male salmon spend several years in oceans before returning to freshwater to reproduce, may actually result from active inhibition of development into a sneaker. Previous studies have found that the proportion of sneakers in various salmon populations varies wildly; it appears that males that grow fastest early in life go on to become sneakers.

The study by Aubin-Horth and her colleagues differed from most examinations of divergent life histories, in any vertebrate species, in that it combined the use of wild individuals, caught in a tributary of the Connecticut River in western Massachusetts, with new functional genomics technologies to simultaneously monitor thousands of genes in individual tissues.

"Research like this was very difficult in the past because we lacked adequate tools to measure gene expression," Aubin-Horth says. "As a result almost nothing is known about the molecular basis of developmental plasticity such as that seen among ’sneaker’ salmon."

Steve Bradt | EurekAlert!
Further information:
http://www.harvard.edu

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>