http://hdl.handle.net/2440/11516 Mon, 20 May 2013 03:14:35 GMT 2013-05-20T03:14:35Z http://hdl.handle.net/2440/76643 Title: Cytokine receptor activation at the cell surface Author: Broughton, Sophie E.; Hercus, Timothy Robert; Lopez, Angel Francisco; Parker, Michael W. Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/76643 2011-12-31T13:30:00Z http://hdl.handle.net/2440/76600 Title: The GM-CSF/IL-3/IL-5 cytokine receptor family: from ligand recognition to initiation of signaling Author: Broughton, Sophie E.; Dhagat, Urmi; Hercus, Timothy Robert; Nero, Tracy L.; Grimbaldeston, Michele Anne; Bonder, Claudine Sharon; Lopez, Angel Francisco; Parker, Michael W. Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/76600 2011-12-31T13:30:00Z http://hdl.handle.net/2440/74387 Title: BiP-mediated closing of the Sec61 channel limits Ca²⁺ leakage from the ER Author: Schauble, Nico; Lang, Sven; Jung, Martin; Cappel, Sabine; Schorr, Stefan; Ulucan, Özlem; Linxweiler, Johannes; Dudek, Johanna; Blum, Robert; Helms, Volkhard; Paton, Adrienne Webster; Paton, James Cleland; Cavalié, Adolfo; Zimmerman, Richard Abstract: In mammalian cells, signal peptide-dependent protein transport into the endoplasmic reticulum (ER) is mediated by a dynamic protein-conducting channel, the Sec61 complex. Previous work has characterized the Sec61 channel as a potential ER Ca²⁺ leak channel and identified calmodulin as limiting Ca²⁺ leakage in a Ca²⁺-dependent manner by binding to an IQ motif in the cytosolic aminoterminus of Sec61α. Here, we manipulated the concentration of the ER lumenal chaperone BiP in cells in different ways and used live cell Ca²⁺ imaging to monitor the effects of reduced levels of BiP on ER Ca²⁺ leakage. Regardless of how the BiP concentration was lowered, the absence of available BiP led to increased Ca²⁺ leakage via the Sec61 complex. When we replaced wild-type Sec61α with mutant Sec61αY344H in the same model cell, however, Ca²⁺ leakage from the ER increased and was no longer affected by manipulation of the BiP concentration. Thus, BiP limits ER Ca²⁺ leakage through the Sec61 complex by binding to the ER lumenal loop 7 of Sec61α in the vicinity of tyrosine 344. Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/74387 2011-12-31T13:30:00Z http://hdl.handle.net/2440/74144 Title: Legionella steelei sp. nov., isolated from human respiratory specimens in California, USA, and South Australia Author: Edelstein, Paul H.; Edelstein, Martha A.; Shephard, Lisa J.; Ward, Kevin W.; Ratcliff, Rodney Mark Abstract: Legionella-like bacteria were isolated from the respiratory tract of two patients in California, USA, and South Australia, but were not thought to cause disease. These bacteria, strains F2632 and IMVS-3376T, were found to have identical Legionella macrophage infectivity potentiator (mip) gene sequences and were therefore further characterized to determine their genetic and phenotypic relatedness and properties. Both of these Gram-negative-staining bacterial strains grew on buffered charcoal yeast extract medium, were cysteine auxotrophs and made a characteristic diffusible bright yellow fluorescent pigment, with one strain making a late appearing colony-bound blue–white fluorescent pigment. The optimal in vitro growth temperature was 35 °C, with very poor growth at 37 °C in broth or on solid media. There was no growth in human A549 cells at either 35 or 37 °C, but excellent growth in Acanthamoeba castellani at 30 °C and poorer growth at 35 °C. Phylogenetic analysis of these bacteria was performed by sequence analysis of 16S rRNA, mip, ribonuclease P, ribosomal polymerase B and zinc metalloprotease genes. These studies confirmed that the new strains represented a single novel species of the genus Legionella for which the name Legionella steelei sp. nov. is proposed. The type strain is IMVS-3376T ( = IMVS 3113T = ATCC BAA-2169T). Description: The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA, mip, proA, rnpB and rpoB gene sequences of strain IMVS-3376T are HQ398202–HQ398206, respectively. Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/74144 2011-12-31T13:30:00Z