To determine the functional role of the metal-dependent conformational changes in Factor IX, two populations of conformation-specific anti-Factor IX antibodies were prepared. Anti-Factor IX X Mg(II) antibodies bind to Factor IX in the presence of Mg(II) and other metal ions, but not in the absence of metal ions. Anti-Factor IX X Ca(II)-specific antibodies bind to Factor IX in the presence of Ca...

Previous genetic and biochemical studies led to the identification of two large RNase T1-resistant oligonucleotides, designated the G(IX) (+) and G(IX) (-) oligonucleotides, whose presence in the genomes of closely related murine leukemia viruses is mutually exclusive and predictive of two properties of the viral envelope glycoprotein gp70. Viruses harboring the G(IX) (+) oligonucleotide induce...

background: hemophilia b is a bleeding disorder with a recessive x-linked inheritance pattern, in which the infected individuals have low levels of factor ix in their plasma. affected individuals may have bleeding episodes after trauma or spontaneously considering the plasma level of factor ix. in order to prevent these episodes and to control bleeding, they should use coagulation factor concen...

This report concerns a cell surface antigen (G(IX); G = Gross) which exhibits mendelian inheritance but which also appears de novo in cells that become productively infected with MuLV (Gross), the wild-type leukemia virus of the mouse. In normal mice, G(IX) is a cell surface allo-antigen confined to lymphoid cells and found in highest amount on thymocytes. Four categories of inbred mouse strain...

The majority of cases of human hemophilia B are the result of missense mutations in the coagulation factor IX gene and defective circulating factor IX is detectable in most patients. The available mouse factor IX knockout models of hemophilia B (FIXKO mouse) reproduce the bleeding phenotype of human hemophilia B, but because the models produce no factor IX they fail to reproduce the dominant hu...

The majority of cases of human hemophilia B are the result of missense mutations in the coagulation factor IX gene and defective circulating factor IX is detectable in most patients. The available mouse factor IX knockout models of hemophilia B (FIXKO mouse) reproduce the bleeding phenotype of human hemophilia B, but because the models produce no factor IX they fail to reproduce the dominant hu...

To evaluate the biosynthetic basis for decreased glycoprotein (GP) Ib-IX expression resulting from GP IX mutations described in three siblings with Bernard-Soulier syndrome, we introduced each mutation into the cDNA for GP IX by site-directed mutagenesis (GP IX Asp21 --> Gly and GP IX Asn45 --> Ser) and examined the associations of the mutants with the two other subunits of the GP Ib-IX complex...

Carbonic anhydrase IX (CA IX) is a well-recognized hypoxia marker with promising diagnostic and therapeutic value. CA IX regulates the pH in hypoxic tumor cells and, thereby, contributes to microenvironmental acidosis and cell migration. To gain a better insight into the molecular processes driven by CA IX, we performed gene expression profiling o...

Residue K5 in factor IX gamma-carboxyglutamic acid (Gla) domain participates in binding endothelial cells/collagen IV. We injected recombinant factor IX containing mutations at residue 5 (K5A, K5R) into factor IX-deficient mice and compared their behavior with that of wild-type factor IX. The plasma concentration of factor IX that binds to endothelial cells/collagen IV (recombinant wild type an...

Carbonic anhydrase IX is a hypoxia-induced transmembrane enzyme linked with solid tumors. It catalyzes the reversible hydration of CO2 providing bicarbonate ions for intracellular neutralization and protons for extracellular acidosis, thereby supporting tumor cell survival and invasiveness. CA IX is the only human CA isoform containing the proteoglycan (PG) domain in its extracellular part. The...