Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers from the Université Libre de Bruxelles show that a rhesus factor controls renal functionand male fertility

20.11.2008
The “Rhesus” blood group is well-known from the public for its importance in the field of transfusion medicine.

For several years, researchers from ULB have been studying Rhesus factors. These factors belong to a family comprising five proteins, three of which are present at the red cell surface (RhCE, RhD and RhAG) and determine the Rhesus blood group, and two others (RhBG and RhCG) which are found in various organs including the kidney, the liver and the male genital tract.

The function of Rhesus factors remained completely unknown till Dr. Anna Maria Marini (Research associate from the FNRS) and her collaborators (Laboratory of Molecular Physiology of the Cell, Prof. Bruno André, ULB, IBMM, Charleroi) established a relationship between Rhesus factors and yeast ammonium transporters. Ammonium is used as a major nitrogen source by microbes and plants but is rather known for its toxicity and its implication in the regulation of blood acidity (pH) in mammals. In 2000, this research group proposes that Rhesus factors play a role in the transport of ammonium in mammals, a process also remaining unknown in animals. This hypothesis was tested by Dr. Sophie Biver during her doctoral thesis performed in the Laboratory of Biology of Development (Profs Josiane and Claude Szpirer, also at IBMM, ULB), in collaboration with the group of Dr. Marini.

The results of their research is published this 20 November in the prestigious review Nature.

The basic idea is simple: to generate mice deprived of the RHCG gene (the one expressed in the kidney) in order to determine if as proposed, these mice would present anomalies related to a defect in ammonium transport, and in particular to a defect in ammonium excretion in the urine. The mice obtained, bearing an invalidation of the RHCG gene and thus deprived of any RhCG protein, appeared viable but their urine contains too low amounts of ammonium, especially if their food is acid, which has for major consequences an altered blood pH which is too acid and a significant loss of weight.

This discovery - which validates the starting assumption – leads to the revision of the concept taught since the 1940th according to which renal ammonium excretion occurs solely by a process of passive diffusion (which does not imply the function of a protein). These mice show the characteristics of human genetic renal pathologies known under the name of distal renal tubular acidosis and whose determinants are not completely known.

Moreover, the researchers observed that invalidated male mice generated litters of reduced size (whereas invalidated females have a normal fertility). This observation is consistent with the fact that the RHCG gene is expressed in the male genital tract where the fluid of the epididymis shows an abnormal pH (it is too acid) in invalidated mice.

These observations have implications in human medicine. They suggest that in man, mutations affecting the RHCG gene could cause some forms of renal pathologies and/or a loss of male fertility. This last suggestion is relevant knowing that certain observations indicate a reduction of the quality of human sperm, in particular in Western populations.

Co-ordinated by the Université libre de Bruxelles- Institut de biologie et de médecine moléculaires, IBMM -, this research was carried out in collaboration with three other teams (Pr. Oliver Devuyst, Université Catholique de Louvain; Pr. C.A. Wagner, Université de Zurich; Dr P. Houillier, Université Pierre et Marie Curie).

A role for Rhesus factor Rhcg in renal ammonium excretion and male fertility.
Biver, S., Belge, H., Bourgeois, S., Van Vooren, P., Novick, M., Scohy, S., Houillier, P., Szpirer, J., Szpirer, C., Wagner, C.A., Devuyst, O., Marini, A.M., Nature, 20 November 2008
Scientific information:
Anna Maria Marini, IBMM-ULB : +32 (0)2 650 99 57, Anna.Maria.Marini@ulb.ac.be

Nancy Dath | alfa
Further information:
http://www.ulb.ac.be

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>