TY - JOUR A1 - Walter, Juliane K. A1 - Rückert, Christine A1 - Voss, Martin A1 - Müller, Sebastian L. A1 - Piontek, Joerg A1 - Gast, Klaus A1 - Blasig, Ingolf E. T1 - The oligomerization of the coiled coil-domain of occluddin is redox sensitive N2 - The transmembrane tight junction protein occludin is sensitive to oxidative stress. Occludin oligomerizes; however, its function in the tight junction is unknown. The cytosolic C-terminal tail contains a coiled coil-domain and forms dimers contributing to the oligomerization. The regulation of the oligomerization remains unclear. As the domain area contains sulfhydryl residues, we tested the hypothesis that the dimerization of the coiled coil-domain depends on these residues. We showed that the dimerization is modulated by the thiol concentration in the low-millimolar range, which is relevant both for physiological and pathophysiological conditions. Masking the sulfhydryl residues in the fragment by covalent binding of 4-vinyl pyridine prevented the dimerization but did not affect its helical structure and cylindric shape. The data demonstrate, for the first time, that disulfide bridge formation of murine cystein 408 is involved in the dimerization. This process is redox-sensitive but the secondary structure of the domain is not. It is concluded that the dimerization of occludin may play a regulatory role in the tight junction assembly under physiological and pathological conditions. Y1 - 2009 UR - http://www3.interscience.wiley.com/cgi-bin/issn?DESCRIPTOR=PRINTISSN&VALUE=0077-8923 U6 - https://doi.org/10.1111/j.1749-6632.2009.04058.x SN - 0077-8923 ER - TY - JOUR A1 - Balazadeh, Salma A1 - Schildhauer, Joerg A1 - Araujo, Wagner L. A1 - Munne-Bosch, Sergi A1 - Fernie, Alisdair R. A1 - Proost, Sebastian A1 - Humbeck, Klaus A1 - Müller-Röber, Bernd T1 - Reversal of senescence by N resupply to N-starved Arabidopsis thaliana: transcriptomic and metabolomic consequences JF - Journal of experimental botany N2 - Leaf senescence is a developmentally controlled process, which is additionally modulated by a number of adverse environmental conditions. Nitrogen shortage is a well-known trigger of precocious senescence in many plant species including crops, generally limiting biomass and seed yield. However, leaf senescence induced by nitrogen starvation may be reversed when nitrogen is resupplied at the onset of senescence. Here, the transcriptomic, hormonal, and global metabolic rearrangements occurring during nitrogen resupply-induced reversal of senescence in Arabidopsis thaliana were analysed. The changes induced by senescence were essentially in keeping with those previously described; however, these could, by and large, be reversed. The data thus indicate that plants undergoing senescence retain the capacity to sense and respond to the availability of nitrogen nutrition. The combined data are discussed in the context of the reversibility of the senescence programme and the evolutionary benefit afforded thereby. Future prospects for understanding and manipulating this process in both Arabidopsis and crop plants are postulated. KW - Arabidopsis KW - gene expression KW - metabolomics KW - nitrogen limitation KW - senescence KW - transcriptome Y1 - 2014 U6 - https://doi.org/10.1093/jxb/eru119 SN - 0022-0957 SN - 1460-2431 VL - 65 IS - 14 SP - 3975 EP - 3992 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Read, Betsy A. A1 - Kegel, Jessica A1 - Klute, Mary J. A1 - Kuo, Alan A1 - Lefebvre, Stephane C. A1 - Maumus, Florian A1 - Mayer, Christoph A1 - Miller, John A1 - Monier, Adam A1 - Salamov, Asaf A1 - Young, Jeremy A1 - Aguilar, Maria A1 - Claverie, Jean-Michel A1 - Frickenhaus, Stephan A1 - Gonzalez, Karina A1 - Herman, Emily K. A1 - Lin, Yao-Cheng A1 - Napier, Johnathan A1 - Ogata, Hiroyuki A1 - Sarno, Analissa F. A1 - Shmutz, Jeremy A1 - Schroeder, Declan A1 - de Vargas, Colomban A1 - Verret, Frederic A1 - von Dassow, Peter A1 - Valentin, Klaus A1 - Van de Peer, Yves A1 - Wheeler, Glen A1 - Dacks, Joel B. A1 - Delwiche, Charles F. A1 - Dyhrman, Sonya T. A1 - Glöckner, Gernot A1 - John, Uwe A1 - Richards, Thomas A1 - Worden, Alexandra Z. A1 - Zhang, Xiaoyu A1 - Grigoriev, Igor V. A1 - Allen, Andrew E. A1 - Bidle, Kay A1 - Borodovsky, M. A1 - Bowler, C. A1 - Brownlee, Colin A1 - Cock, J. Mark A1 - Elias, Marek A1 - Gladyshev, Vadim N. A1 - Groth, Marco A1 - Guda, Chittibabu A1 - Hadaegh, Ahmad A1 - Iglesias-Rodriguez, Maria Debora A1 - Jenkins, J. A1 - Jones, Bethan M. A1 - Lawson, Tracy A1 - Leese, Florian A1 - Lindquist, Erika A1 - Lobanov, Alexei A1 - Lomsadze, Alexandre A1 - Malik, Shehre-Banoo A1 - Marsh, Mary E. A1 - Mackinder, Luke A1 - Mock, Thomas A1 - Müller-Röber, Bernd A1 - Pagarete, Antonio A1 - Parker, Micaela A1 - Probert, Ian A1 - Quesneville, Hadi A1 - Raines, Christine A1 - Rensing, Stefan A. A1 - Riano-Pachon, Diego Mauricio A1 - Richier, Sophie A1 - Rokitta, Sebastian A1 - Shiraiwa, Yoshihiro A1 - Soanes, Darren M. A1 - van der Giezen, Mark A1 - Wahlund, Thomas M. A1 - Williams, Bryony A1 - Wilson, Willie A1 - Wolfe, Gordon A1 - Wurch, Louie L. T1 - Pan genome of the phytoplankton Emiliania underpins its global distribution JF - Nature : the international weekly journal of science N2 - Coccolithophores have influenced the global climate for over 200 million years(1). These marine phytoplankton can account for 20 per cent of total carbon fixation in some systems(2). They form blooms that can occupy hundreds of thousands of square kilometres and are distinguished by their elegantly sculpted calcium carbonate exoskeletons (coccoliths), rendering them visible from space(3). Although coccolithophores export carbon in the form of organic matter and calcite to the sea floor, they also release CO2 in the calcification process. Hence, they have a complex influence on the carbon cycle, driving either CO2 production or uptake, sequestration and export to the deep ocean(4). Here we report the first haptophyte reference genome, from the coccolithophore Emiliania huxleyi strain CCMP1516, and sequences from 13 additional isolates. Our analyses reveal a pan genome (core genes plus genes distributed variably between strains) probably supported by an atypical complement of repetitive sequence in the genome. Comparisons across strains demonstrate that E. huxleyi, which has long been considered a single species, harbours extensive genome variability reflected in different metabolic repertoires. Genome variability within this species complex seems to underpin its capacity both to thrive in habitats ranging from the equator to the subarctic and to form large-scale episodic blooms under a wide variety of environmental conditions. Y1 - 2013 U6 - https://doi.org/10.1038/nature12221 SN - 0028-0836 SN - 1476-4687 VL - 499 IS - 7457 SP - 209 EP - 213 PB - Nature Publ. Group CY - London ER -