Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UI researchers advance understanding of sexual evolution

26.01.2005


University of Iowa researchers have uncovered evidence of sexual reproduction in a single-celled organism long thought to reproduce asexually, according to a paper published in the January 26, 2005 issue of the journal Current Biology.



The finding by John M. Logsdon, Jr., assistant professor in the UI College of Liberal Arts and Sciences Department of Biological Sciences and the Roy J. Carver Center for Comparative Genomics, and colleagues from the UI and Roanoke College (Virginia), provides the first clear evidence that meiosis arose very early in eukaryotic evolution, bringing science one step closer to understanding the mystery of sexual evolution.

The paper, "A Phylogenomic Inventory of Meiotic Genes: Evidence for Sex in Giardia and an Early Eukaryotic Origin of Meiosis," describes their work studying eukaryotes (cells having nuclei, including plants, animals and fungi). By looking for genes necessary for sexual reproduction, the researchers uncovered evidence that eukaryotic cells have been capable of sex for a very long time. Recent evolutionary analyses of the genome of Giardia intestinalis, a unicellular protist (microbial eukaryote) parasite that represents an early-branching lineage of eukaryotes, has revealed the presence of numerous genes implicated in meiosis -- the cellular division process that results in gametes (haploid reproductive cells).


Logsdon says: "Most eukaryotes are known to have sexual cycles and meiosis, but such processes are unknown in some single-celled protists (protozoa). Despite over a century of study, Giardia intestinalis was not known to have a sex life. And since Giardia is thought to be a modern representative of one of the earliest diverging eukaryotic lineages, it was suspected to simply have never acquired meiosis. But the inability to observe processes does not necessarily mean that they are not present."

In their new work, Logsdon and colleagues Marilee Ramesh and Banoo Malik (all previously at Emory University) surveyed the genome sequence of Giardia. (The Giardia genome is being completed by Mitch Sogin and colleagues at the Marine Biological Laboratory, Wood’s Hole, Mass.) In this genome, Logsdon and colleagues found clear evidence for meiosis in Giardia; in particular, five genes that encode meiosis-specific proteins are present in Giardia and broadly in other eukaryotes. These data suggest that Giardia is capable of sex and that the earliest eukaryotes diverged after the advent of this key biological process.

Logsdon and his colleagues plan to continue their research by investigating the function of these genes in Giardia. He says: "Now that we have found these genes, we want to know what they are doing and when they are doing it." Logsdon’s group is also extending their approach to other species in which sex has not been documented. Logsdon says, "This will help us to understand if meiosis is a requirement of all eukaryotes."

Gary Galluzzo | EurekAlert!
Further information:
http://www.uiowa.edu

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>