Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Restricting the gene pool

15.10.2003


Nature has evolved clever ways to prevent animals from different species from successfully reproducing. As published in the upcoming issue of Genes & Development, molecular biologists at UC Irvine are gaining a better understanding as to how.



In the October 15th issue, Drs. Noriko Kamei and Charles Glabe report on the identification of a receptor on the surface of sea urchin eggs that regulates the species-specific adhesion of sperm.

External fertilization can be risky business, especially for marine animals whose sperm is released into an aqueous environment. Thus, there are several barriers to prevent cross-fertilization between different species of sea urchins, or even, say, sea horse sperm from fertilizing sea urchin eggs. The recognition of egg and sperm involves a number of steps (sperm attraction, activation, and adhesion to the egg surface), each of which serves as a checkpoint to restrict the gene pool to individuals of the same species.


Over 25 years ago, scientists discovered that at the tip of sea urchin sperm exists a protein that mediates binding of the sperm to the egg – a protein they named "bindin." Each species of sea urchin has its own unique version of bindin, and scientists hypothesized that each species’ egg must, likewise, have a similarly unique bindin receptor on its surface. Since then, species-specific sperm adhesive proteins and egg receptors have been identified in other animals, including mammals, but the identity of the sea urchin egg bindin receptor has remained elusive. Until now.

Drs. Kamei and Glabe have identified the species-specific sea urchin egg bindin receptor, which they call EBR1 (egg bindin receptor 1). Drs. Kamei and Glabe searched through complementary DNA sequences from ovaries of two different species of sea urchins (S. franciscanus and S. purpuratus, or Sf and Sp, respectively). The scientists were looking for sequences that were present in one species but not the other, and therefore might encode a species-specific protein. Of the four Sf-specific DNA sequences they found, only one was sufficiently large to encode the expected size of the bindin receptor.

Drs. Kamei and Glabe undertook several different experimental approaches to test the validity of this putative bindin receptor, and all roads led to the same conclusion: EBR1 is the long sought after egg bindin receptor. Structural analysis revealed that while Sf-EBR1 and Sp-EBR1 proteins share a conserved core domain, they also have a unique region that accounts for the proteins’ species-specific activity.

"Having the sperm and egg molecules (bindin/EBR1) in hand will allow study at a molecular level of how sperm and egg interact to make fertile offspring. Such insights could provide an understanding of common structural features and functional principals of molecules involved in mammalian gamete interactions. It also may she light on how new species evolved," explains Dr. Kamei.

Heather Cosel | EurekAlert!
Further information:
http://www.cshl.org/

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 >>>