The sodium-iodide symporter (NIS) is an integral membrane protein that plays a crucial role in iodide accumulation, especially in the thyroid. As for many other membrane proteins, its intracellular sorting and distribution have a tremendous effect on its function, and constitute an important aspect of its regulation. Many short sequences have been shown to contribute to protein trafficking along the sorting or endocytic pathways.
View Article and Find Full Text PDFρ-Da1a is a three-finger fold toxin from green mamba venom that is highly selective for the α1A-adrenoceptor. This toxin has atypical pharmacological properties, including incomplete inhibition of (3)H-prazosin or (125)I-HEAT binding and insurmountable antagonist action. We aimed to clarify its mode of action at the α1A-adrenoceptor.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
June 2013
ρ-Da1a toxin from eastern green mamba (Dendroaspis angusticeps) venom is a polypeptide of 65 amino acids with a strong affinity for the G-protein-coupled α(1A)-adrenoceptor. This neurotoxin has been crystallized from resolubilized lyophilized powder, but the best crystals grew spontaneously during lyophilization. The crystals belonged to the trigonal space group P3(1)21, with unit-cell parameters a = b = 37.
View Article and Find Full Text PDFThe 739-amino-acid nucleoprotein (NP) of Zaire Ebolavirus (ZEBOV) plays a key role in Ebola virion formation and replication. A stable HEK-293 cell line capable of producing an N-ter 6His-tagged recombinant form of NP - ZEBOV was created. Production of this protein was triggered in batch culture using microcarriers.
View Article and Find Full Text PDFHuman checkpoint kinase 2 is a major actor in checkpoint activation through phosphorylation by ataxia telangiectasia mutated in response to DNA double-strand breaks. In the absence of de novo DNA damage, its autoactivation, reported in the event of increased Cds1/checkpoint kinase 2 (Chk2) expression, has been attributed to oligomerization. Here we report a study performed on autoactivated recombinant Chk2 proteins that aims to correlate kinase activity and phosphorylation status.
View Article and Find Full Text PDFMany regulatory proteins undergo transient nuclear relocation under physical or chemical stress. This phenomenon is, however, difficult to assess due to the lack of sensitive and standardized biological assays. Here, we describe a new quantitative nuclear relocation assay (QNR), based on expression in yeasts of chimeric proteins in which an artificial transcription factor is fused to a target protein acting as driver for relocation.
View Article and Find Full Text PDFEukaryotic cells have evolved DNA damage checkpoints in response to genome damage. They delay the cell cycle and activate repair mechanisms. The kinases at the heart of these pathways and the accessory proteins, which localize to DNA lesions and regulate kinase activation, are conserved from yeast to mammals.
View Article and Find Full Text PDFJ Biol Chem
August 2003
Although coenzymeA (CoA) is essential in numerous metabolic pathways in all living cells, molecular characterization of the CoA biosynthetic pathway in Archaea remains undocumented. Archaeal genomes contain detectable homologues for only three of the five steps of the CoA biosynthetic pathway characterized in Eukarya and Bacteria. In case of phosphopantetheine adenylyltransferase (PPAT) (EC 2.
View Article and Find Full Text PDF