Tuesday June 16, from 12.00 to 13.00 at the Auditorium Albert Claude, Point Centre
(this seminar will be followed by a lunch from 13.00 to 14.00)

Common Seminar IBMM-IMI with Anna Maria MARINI
Physiology Moleculaire de la Cellule, ULB, Gosselies

"From yeast ammonium transport proteins to human Rhesus factors"

Ammonium is a principal nitrogen source for microorganisms and plants, whereas in animals it is a metabolic product best known for its cytotoxic effects. Ammonium handling is also critical for systemic pH regulation, renal ammonium production and excretion being essential for net acid elimination. Although specific ammonium transport systems might play important roles in all domains of life, the study of such proteins has been hampered by a lack of molecular characterisation. In 1994, using the yeast Saccharomyces cerevisiae as a model, we cloned the first gene encoding an ammonium transport protein which defined a widely conserved family. We next found that the Rhesus factors, including the human antigens from the Rhesus blood group, belong to this novel family. More recently, by targeting the Rhcg gene in mouse, we showed that the corresponding Rhesus protein is required for urinary ammonium excretion and for the regulation of acid-base homeostasis.