Previously we cloned a polyspecific transporter from rat (rOCT1) that is expressed in renal proximal tubules and hepatocytes mediates electrogenic uptake of organic cations with different molecular structures. Recently homologous kidney (rOCT2) was but not characterized detail. We report cloning characterization two transporters man (hOCT1 hOCT2) displaying approximately 80% amino acid identity to rOCT1 rOCT2, respectively. Northern blots showed hOCT1 mainly transcribed liver, while hOCT2...

Recently, we cloned the human cation transporter hOCT2, a member of new family polyspecific transporters from kidney, and demonstrated electrogenic uptake tetraethylammonium, choline, N¹-methylnicotinamide, 1-methyl-4-phenylpyridinium. Using polymerase chain reaction amplification, cDNA sequencing,<i>in situ</i> hybridization, immunohistochemistry, now show that hOCT2 message protein are expressed in neurons cerebral cortex various subcortical nuclei. In <i>Xenopus laevis</i>...

We have isolated KCNQ5, a novel human member of the KCNQ potassium channel gene family that is differentially expressed in subregions brain and skeletal muscle. When in<i>Xenopus</i> oocytes, KCNQ5 generated voltage-dependent, slowly activating K⁺-selective currents displayed marked inward rectification at positive membrane voltages. were insensitive to K⁺ blocker tetraethylammonium but strongly inhibited by selective M-current linopirdine. Upon coexpression with...

The widely used histamine receptor antagonists terfenadine and astemizole were shown to prolong the QT interval in electrocardiographic recordings cases of overdose or inappropriate co‐medications, indicating a possible interaction with cardiac K + channels. Here, both inhibited h uman e ther‐a‐go‐go r elated gene (HERG) encoded channels expressed Xenopus oocytes at nanomolar concentrations use‐ voltage‐dependent fashion. In contrast, inhibition other delayed rectifier (Kvl.1 I sK ) inward...

The antipsychotic drug haloperidol can induce a marked QT prolongation and polymorphic ventricular arrhythmias. In this study, we expressed several cloned cardiac K + channels, including the human ether‐a‐go‐go related gene (HERG) in Xenopus oocytes tested them for their sensitivity. Haloperidol had only little effects on delayed rectifier channels Kv1.1, Kv1.2, Kv1.5 I sK , A‐type channel Kv1.4 inward Kir2.1 (inhibition &lt;6% at 3 μ m haloperidol). contrast, blocked HERG potently with an...

The previously cloned rat cation transporter rOCT1 detected in renal proximal tubules and hepatocytes (Gründemann, D., Gorboulev, V., Gambaryan, S., Veyhl, M., Koepsell, H. (1994) Nature 372, 549-552) was expressed Xenopus oocytes, transport properties were analyzed using tracer uptake studies electrophysiological measurements. induced highly active of a variety cations, including the classical substrates for transport, such as N-1-methylnicotinamide, 1-methyl-4-phenylpyridinium (MPP),...

The basic question addressed in this study is how energy metabolism adjusted to cope with iron deficiency Chlamydomonas reinhardtii. To investigate the impact of on bioenergetic pathways, comparative proteomics was combined spectroscopic as well voltametric oxygen measurements assess protein dynamics linked functional properties respiratory and photosynthetic machineries. Although electron transfer largely compromised under deficiency, our quantitative data revealed that antenna size...

Abstract The plant-specific calcium binding protein CAS (calcium sensor) has been localized in chloroplast thylakoid membranes of vascular plants and green algae. To elucidate the function Chlamydomonas reinhardtii, we generated analyzed eight independent knockdown C. reinhardtii lines (cas-kd). Upon transfer to high-light (HL) growth conditions, cas-kd were unable properly induce expression LHCSR3 that is crucial for nonphotochemical quenching. Prolonged exposure HL revealed a severe light...

Background— Inhibition of tyrosine kinases, including platelet-derived growth factor receptor, can reduce pulmonary arterial pressure in experimental and clinical hypertension. We hypothesized that inhibition the serine/threonine kinases Raf-1 (also termed c-Raf) b-Raf addition to effectively controls vascular right heart remodeling Methods Results— investigated effects novel multikinase inhibitor sorafenib, which inhibits as well comparison imatinib, a kinase inhibitor, on hemodynamics,...

Abstract Enzyme replacement therapy (ERT) is an effective treatment for several lysosomal storage disorders (LSDs). Intravenously infused enzymes are taken up by tissues through either the mannose 6‐phosphate receptor (M6PR) or (MR). It generally believed that M6PR‐mediated endocytosis a key mechanism ERT in treating LSDs affect non‐macrophage cells of visceral organs. However, therapeutic efficacy MR‐mediated delivery mannose‐terminated these diseases has not been fully evaluated. We tested...

1. We identified the ethacrynic-acid derivative DCPIB as a potent inhibitor of I(Cl,swell), which blocks native I(Cl,swell) calf bovine pulmonary artery endothelial (CPAE) cells with an IC(50) 4.1 microM. Similarly, 10 microM almost completely inhibited swelling-induced chloride conductance in Xenopus oocytes and guinea-pig atrial cardiomyocytes. Block by was fully reversible voltage independent. 2. (10 microM) showed selectivity for had no significant inhibitory effects on I(Cl,Ca) CPAE...

Mutations in the rBAT gene cause type I cystinuria, a common inherited aminoaciduria of cystine and dibasic amino acids due to their defective renal intestinal reabsorption (Calonge, M. J., Gasparini, P., Chillarón, Chillón, M., Gallucci, Rousaud, F., Zelante, L., Testar, X., Dallapiccola, B., Di Silverio, Barceló, Estivill, Zorzano, A., Nunes, V., Palacín, (1994) Nat. Genet. 6, 420-426; Calonge, Volipini, Bisceglia, De Sanctis, Beccia, E., (1995) Proc. Natl. Acad. Sci. U. S. A. 92,...

We report the primary sequence of TASK-4, a novel member acid-sensitive subfamily tandem pore K(+) channels. TASK-4 transcripts are widely expressed in humans, with highest levels liver, lung, pancreas, placenta, aorta and heart. In Xenopus oocytes generated currents displaying marked outward rectification which was lost by elevation extracellular K(+). were efficiently blocked barium (83% inhibition at 2 mM), only weakly inhibited 1 mM concentrations quinine, bupivacaine lidocaine, but not...

Extracellular tetraethylammonium (TEA) inhibits currents in Xenopus oocytes that have been injected with mRNAs encoding voltage-dependent potassium channels. Concentration-response curves were used to measure the affinity of TEA; this differed up 700-fold among channels RBK1 (KD 0.3 mM), RGK5 11 and RBK2 greater than 200 mM). Studies which chimeric expressed localized TEA binding putative extracellular loop between trans-membrane domains S5 S6. Site-directed mutagenesis residues region...

Two distinct molecular types (I and II) of renal proximal tubular brush border Na+/Pi cotransporters have been identified by expression cloning on the basis their capacity to induce Na+-dependent Pi influx in tracer experiments. Whereas type II transporters (e.g., NaPi-2 NaPi-3) resemble well known characteristics cotransport, little is about properties I transporter (NaPi-1). In contrast II, produced electrogenic transport only at high extracellular concentrations (&gt; or =3 mM). On other...

Iron deficiency induces a remodeling of the photosynthetic apparatus in Chlamydomonas reinhardtii. In this study we showed that key mechanistic event process photosystem I (PSI) and its associated light-harvesting proteins (LHCI) is N-terminal processing Lhca3. Lhca3 documented independently by two-dimensional gel electrophoresis tandem mass spectrometric (MS/MS) analysis as well quantitative comparative MS/MS peptide profiling using isotopic labeling proteins. Dynamic LHCI complex under...

PGRL1 RNA and protein levels are increased in iron-deficient Chlamydomonas reinhardtii cells. In an RNAi strain, which accumulates lower both iron-replete -starved conditions, the photosynthetic electron transfer rate is decreased, respiratory capacity iron-sufficient conditions increased, efficiency of cyclic under iron-deprivation diminished. Pgrl1-kd cells exhibit iron deficiency symptoms at higher concentrations than wild-type cells, although not more depleted cellular relative to as...

Abstract Moss‐aGalactosidase A (moss‐aGal) is a moss‐derived version of human α‐galactosidase developed for enzyme replacement therapy in patients with Fabry disease. It exhibits homogenous N‐glycosylation profile &gt;90% mannose‐terminated glycans. In contrast to mammalian cell produced α‐galactosidase, moss‐aGal does not rely on mannose‐6‐phosphate receptor mediated endocytosis but targets the mannose tissue uptake. We conducted phase 1 clinical trial six confirmed diagnosis disease during...