title: Generation and characterisation of Rhd and Rhag null mice.
abstract: Mouse Rhd* and Rhag* genes were targeted using insertional vectors; the resulting knockout mice, and double-knockout descendants, were analysed. Rhag glycoprotein deficiency entailed defective assembly of the erythroid Rh complex with complete loss of Rh and intercellular adhesion molecule 4 (ICAM-4), but not CD47, expression. Absence of the Rh protein induced a loss of ICAM-4, and only a moderate reduction of Rhag expression. Double knockout phenotype was similar to that of Rhag targeted mice. Rhd and Rhag deficient mice exhibited neither the equivalent of human Rh(null) haemolytic anaemia nor any clinical or cellular abnormalities. Rhd-/- and Rhag-/- erythrocytes showed decreased basal adhesion to an endothelial cell line resulting from defective ICAM-4 membrane expression. There was no difference in recovery from phenylhydrazine-induced haematopoietic stress for double knockout mice as compared to controls, suggesting that ICAM-4 might be dispensable during stress erythropoiesis. Ammonia and methylammonia transport in erythrocytes was severely impaired in Rhag-/- but only slightly in Rhd-/- animals that significantly expressed Rhag, supporting the view that RhAG and Rhag, but not Rh, may act as ammonium transporters in human and mouse erythrocytes. These knockout mice should prove useful for further dissecting the physiological roles of Rh and Rhag proteins in the red cell membrane.
authors.affiliation: Institut National de la Transfusion Sanguine, 6 rue Alexandre Cabanel, Paris, France. dominique.goossens@inserm.fr
authors.forename: Dominique
authors.initials: D
authors.lastname: Goossens
authors.forename: Marie-Marcelle
authors.initials: MM
authors.lastname: Trinh-Trang-Tan
authors.forename: Martine
authors.initials: M
authors.lastname: Debbia
authors.forename: Pierre
authors.initials: P
authors.lastname: Ripoche
authors.forename: Camilo
authors.initials: C
authors.lastname: Vilela-Lamego
authors.forename: Fawzia
authors.initials: F
authors.lastname: Louache
authors.forename: William
authors.initials: W
authors.lastname: Vainchenker
authors.forename: Yves
authors.initials: Y
authors.lastname: Colin
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Cartron
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000235:genetics; D001798:Blood Proteins / Q000172:deficiency* / Q000235:genetics / Q000502:physiology; D002448:Cell Adhesion / Q000235:genetics; D015815:Cell Adhesion Molecules / Q000172:deficiency / Q000502:physiology; D002478:Cells, Cultured; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000502:physiology; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism; D004920:Erythropoiesis / Q000502:physiology; D005260:Female; D008297:Male; D008562:Membrane Glycoproteins / Q000172:deficiency* / Q000235:genetics / Q000502:physiology; D008744:Methylamines / Q000097:blood; D051379:Mice; D018345:Mice, Knockout; D010641:Phenotype; D000644:Quaternary Ammonium Compounds / Q000097:blood; D012204:Rh-Hr Blood-Group System / Q000235:genetics / Q000502:physiology*
chemical_list: D001798:Blood Proteins; D015815:Cell Adhesion Molecules; C548377:ICAM-4 protein, mouse; D008562:Membrane Glycoproteins; D008744:Methylamines; D000644:Quaternary Ammonium Compounds; D012204:Rh-Hr Blood-Group System; C401210:Rhag protein, mouse; C026410:Rho(D) antigen; C027451:methylamine