A methodological approach to investigate steady state fucoxanthin chlorophyll a/c binding protein mRNA levels in Wadden Sea sediments Autors/ores Telse Meyer Geomikrobiologie, ICBM, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany Michael Hust FB Biologie, Lehrgebiet Molekulargenetik, Universität Hannover, Hannover, Germany Jürgen Marquardt Department of Biochemistry and Molecular Biology, Penn State University, USA Wolfgang E. Krumbein Geomikrobiologie, ICBM, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany Erhard Rhiel Geomikrobiologie, ICBM, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany Paraules clau: diatoms, field studies, gene expression, light-harvesting complexes Resum A method was established to investigate the steady state levels of mRNAs from genes encoding fucoxanthin chlorophyll a/c binding proteins (Fcp) of diatoms in situ. During the study, which was performed withWadden Sea sediments from the German North Sea shore near Dangast, oxygenic photosynthesis was carried out mainly by pennate diatoms. Field samples were taken after tidal exposure from dawn up to late afternoon at 2-hourly intervals, and frozen in liquid nitrogen. In the laboratory, total RNA was isolated by isopycnic ultracentrifugation in caesium chloride gradients. Yields of approximately 10–300 μg RNA per gram wet sediment were obtained. Defined amounts of total RNA were blotted onto nylon membranes and hybridised with probes against the fcp2 and 18S rDNA genes of Cyclotella cryptica. To estimate the steady state amount of fcp mRNAs, fcp signal intensities were normalized to the signal intensities obtained from hybridisation to an 18S rDNA gene probe. In the two time-course studies performed to demonstrate the applicability of the method, the steady state levels of fcp mRNA increased up to 12-fold with the onset of light, reaching a maximum 6–8 h after sunrise before they decreased again. Possible reasons for this time-course are discussed. Descàrregues PDF (English) Publicat 2010-03-09 Número Vol. 6 Núm. 1 (2003) Secció Articles Llicència Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.