Ubiquitination plays a crucial role in regulating protein turnover. Here we show that ubiquitination regulates the stability of the MDR1 gene product, P-glycoprotein, thereby affecting the functions of this membrane transporter that mediates multidrug resistance. We found that P-glycoprotein was constitutively ubiquitinated in drug-resistant cancer cells. Transfection of multidrug-resistant cel...

A sialylated glycopeptide isolated after Pronase digestion of human Tamm-Horsfall glycoprotein behaves as a powerful monovalent hapten in the precipitin reaction between human Tamm-Horsfall glycoprotein and leucoagglutinin, but fails to inhibit the interaction of the glycoprotein with rabbit anti-(human Tamm-Horsfall glycoprotein) antibodies. The glycopeptide is much less active than the intact...

Antibodies against β2-glycoprotein I are a subset of very heterogeneous family of antiphospholipid antibodies. It is well recognised that anti-β2-glycoprotein I antibodies are the main pathogenic players in the autoimmune disease known as antiphospholipid syndrome. Many mechanisms have been proposed through which these autoantibodies could cause microplacental, arterial or venous thrombosis. On...

Continuous use of St. John's wort decreases the bioavailabilities of a variety of drugs. This interaction is attributed to the induction of cytochrome P450 3A4 and/or P-glycoprotein. In this study, we aimed to examine the chronic effects of St. John's wort and its constituents, hyperforin and hypericin, on the expression and function of P-glycoprotein in an intestinal cell line, LS 180. We also...

etiologic factors for recurrent miscarriage (rm) include autoimmune diseases, the most frequently antiphospholipid syndrome and thyroiditis. some women who suffer from rm might also have an altered immune system. we aimed to evaluate possible associations between anti-thyroid and anti-phospholipid antibodies in women with rm. in a retrospective case series 1 on 156 women with rm, major outcome ...

Two glycoprotein fractions, A and B, were isolated from bovine achilles tendon. Glycoprotein A was prepared from a 0.2m-sodium chloride extract and glycoprotein B was isolated from a 3m-magnesium chloride extract. They were free from serum proteins. Glycoprotein A was essentially free of collagen, but glycoprotein B contained about 8% collagen. Both glycoproteins gave several bands on isoelectr...

Metastasis is a serious and often life-threatening condition, representing the leading cause of death among women with breast cancer (BC). Although current clinical classification BC well-established, addition minimally invasive laboratory tests based on peripheral blood biomarkers that reflect pathological changes in body utmost importance. In study, serum proteome lipidome profiles for 50 pat...

conclusions these findings of the present study indicate that the recombinant coree1e2 glycoprotein is effective in inducing neutralizing antibodies, and is an influential hcv vaccine candidate. results in our study, the virus-like particle of rcoree1e2 with 70 nm size, was shown by electron microscopy and proved the self-assembly in vitro in a yeast expression system. materials and methods by ...

The elaboration of enamel matrix glycoprotein was investigated in secretory ameloblasts of incisor teeth in 30-40-g rats. To this end, the distribution of glycoprotein was examined histochemically by the use of phosphotungstic acid at low pH, while the formation of glycoprotein was traced radioautographically in animals sacrificed 2.5-30 min after galactose-(3)H injection. Histochemically, the ...

P-glycoprotein, the most extensively studied ATP-binding cassette (ABC) transporter, functions as a biological barrier by extruding toxins and xenobiotics out of cells. In vitro and in vivo studies have demonstrated that P-glycoprotein plays a significant role in drug absorption and disposition. Because of its localisation, P-glycoprotein appears to have a greater impact on limiting cellular up...