A role for the copper transporter, ATP7B, in secretion of copper from the human breast into milk has previously not been reported, although it is known that the murine ortholog of ATP7B facilitates copper secretion in the mouse mammary gland. We show here that ATP7B is expressed in luminal epithelial cells in both the resting and lactating human breast, where it has a perinuclear localization i...

ATP7B is a P-type ATPase involved in copper transport and homeostasis. In experiments with microsomes isolated from COS-1 cells or HepG2 hepatocytes sustaining ATP7B heterologous expression, we found that ATP7B utilization of ATP includes autophosphorylation of an aspartyl residue serving as ATPase catalytic intermediate as well as phosphorylation of serine residues by protein kinase D (PKD). T...

ATP7A and ATP7B are P-type ATPases required for copper homeostasis and involved in the etiology of Menkes and Wilson diseases. We used heterologous expression of ATP7A or ATP7B in COS-1 cells infected with adenovirus vectors to characterize differential features pertinent to each protein expressed in the same mammalian cell type, rather than to extrinsic factors related to different cells susta...

AIM To study the genotype phenotype correlation in Wilson's disease (WD) patients within families. METHODS We report four unrelated families from South India with nine members affected with WD. Phenotype was classified as per international consensus phenotypic classification of WD. DNA was extracted from peripheral blood and 21 exons of ATP7B gene and flanking introns were amplified by polyme...

BACKGROUND Wilson disease (WD) is an autosomal recessive disorder. The WD gene, ATP7B, encodes a copper-transporting ATPase involved in the transport of copper into the plasma protein ceruloplasmin and in excretion of copper from the liver. ATP7B mutations cause copper to accumulate in the liver and brain. OBJECTIVES We examined the ATP7B mutation spectrum in Wilson disease patients in Iran. ...

Wilson's disease (WD) is an autosomal recessive inherited disorder caused by mutations in the ATPase Cu(2+) transporting beta polypeptide gene (ATP7B). The detailed metabolism of copper-induced pathology in WD is still unknown. Gene mutations as well as the possible pathways involved in the ATP7B deficiency were documented. The ATP7B gene was analyzed for mutations in 18 Chinese Han families wi...

We have analyzed the functional effect of site-directed mutations and deletions in the copper-binding domain of ATP7B (the copper transporting P-type ATPase defective in Wilson disease) using a yeast complementation assay. We have shown that the sixth copper-binding motif alone is sufficient, but not essential, for normal ATP7B function. The N-terminal two or three copper-binding motifs alone a...

BACKGROUND Wilson's disease (WD) is an autosomal recessive disorder leading to copper overload, mainly in the liver and brain, due to mutations in the ATP7B gene. About 10% of heterozygous carriers of ATP7B gene mutations have decreased serum ceruloplasmin, posing diagnostic difficulties. CASE REPORT We report a four-member family wherein the 11-year-old daughter was diagnosed as having WD ba...

Toxic milk (tx) is a copper disorder of mice that causes a hepatic accumulation of copper similar to that seen in patients with Wilson disease. Both disorders are caused by a defect in the ATP7B copper-transporting ATPase. A feature of the tx phenotype is the production of copper-deficient milk by lactating dams homozygous for the tx mutation; the milk is lethal to the pups. It has not been det...

The cellular machinery responsible for Cu(+)-stimulated delivery of the Wilson-disease-associated protein ATP7B to the apical domain of hepatocytes is poorly understood. We demonstrate that myosin Vb regulates the Cu(+)-stimulated delivery of ATP7B to the apical domain of polarized hepatic cells, and that disruption of the ATP7B-myosin Vb interaction reduces the apical surface expression of ATP...