Zwischen traditioneller Dialektologie und digitaler Geolinguistik: Der Audioatlas siebenbürgisch-sächsischer Dialekte (ASD)

Der vorliegende Band markiert für die Herausgeber einen Wendepunkt: Er war zunächst ausschließlich als gedrucktes Buch für die Veröffentlichung einer Reihe von Vorträgen zur Arbeitstagung des vom Bundesbeauftragten für Kultur und Medien geförderten Projekts „Audioatlas Siebenbürgisch-Sächsischer Dialekte“ konzipiert worden. Die Tatsache, dass diesem Projekt jedoch im Wesentlichen eine Sammlung von Tonaufnahmen zu Grunde liegt, ließ diese Publikationform schnell als unzulänglich erscheinen. So reifte ganz selbstverständlich der Entschluss, die hier vorgelegten Texte zusätzlich in zeitgemäßer Form im Internet zu veröffentlichen und dabei, die dort gegebenen Möglichkeiten konsequent nutzend, auch Hörbeispiele aus dem Audioatlas einzubinden (http://www.kit.gwi.uni-muenchen.de/). Die doppelte Publikation als Buch und im Netz symbolisiert aus Sicht der Herausgeber den Übergang von der traditionellen zu einer zeitgemäßen Veröffentlichungspraxis mit all ihren technischen Möglichkeiten und ökonomischen Vorteilen

TWISTED DWARF1 mediates the action of auxin transport inhibitors on actin cytoskeleton dynamics

Plant growth and architecture is regulated by the polar distribution of the hormone auxin. Polarity and flexibility of this process is provided by constant cycling of auxin transporter vesicles along actin filaments, coordinated by a positive auxin-actin feedback loop. Both polar auxin transport and vesicle cycling are inhibited by synthetic auxin transport inhibitors, such as 1-N-naphthylphthalamic acid (NPA), counteracting the effect of auxin; however, underlying targets and mechanisms are unclear. Using NMR, we map the NPA binding surface on the Arabidopsis thaliana ABCB chaperone TWISTED DWARF1 (TWD1). We identify ACTIN7 as a relevant, although likely indirect, TWD1 interactor, and show TWD1-dependent regulation of actin filament organization and dynamics and that TWD1 is required for NPA-mediated actin cytoskeleton remodeling. The TWD1-ACTIN7 axis controls plasma membrane presence of efflux transporters, and as a consequence act7 and twd1 share developmental and physiological phenotypes indicative of defects in auxin transport. These can be phenocopied by NPA treatment or by chemical actin (de)stabilization. We provide evidence that TWD1 determines downstream locations of auxin efflux transporters by adjusting actin filament debundling and dynamizing processes and mediating NPA action on the latter. This function appears to be evolutionary conserved since TWD1 expression in budding yeast alters actin polarization and cell polarity and provides NPA sensitivity

TbU1-70K is a U1 snRNP-specific protein and binds specifically to the 5′ loop sequence of U1 snRNA

<p><b>Copyright information:</b></p><p>Taken from "U1 small nuclear RNP from : a minimal U1 snRNA with unusual protein components"</p><p>Nucleic Acids Research 2005;33(8):2493-2503.</p><p>Published online 29 Apr 2005</p><p>PMCID:PMC1087902.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> () Comparison of the domain structures of (Tb08.4A8.530) and the human U1-70K (A25707) proteins. () Western blot analysis of U1 snRNP proteins. U1 snRNPs were affinity-purified from extract by a 2′--methyl RNA antisense oligonucleotide, protein was prepared and analyzed by SDS–PAGE and western blotting, using polyclonal rabbit antibodies against TbU1-70K (U1-70K) or non-immune serum (NIS). The arrow points to the immunostained TbU1-70K band of apparent molecular weight 40 kDa. Protein markers are on the right (in kDa). () U1 snRNA is specifically coprecipitated from extract by anti-Tb U1-70 antibodies. Immunoprecipitations were carried out from extract, using NIS, or with antibodies against the TbU1-70K protein (U1-70K) or against the trypanosome Sm proteins (Sm). RNA was purified from the immunoprecipitates and analyzed by 3′ end labeling with [P]pCp. The positions of the SL RNA and snRNAs are marked on the right. , P-labeled pBR322/HpaII markers. () RNA from the same immunoprecipitates was also analyzed by primer extension with a U1-specific oligonucleotide. In addition, RNA from a 10% aliquot of the input was included; the positions of the primer () and the U1-specific primer-extension product (U1) are marked on the right. , P-labeled pBR322/HpaII markers. () P-labeled U1 snRNA and mutant derivatives [as indicated above the lanes; see (F)] were transcribed and incubated with GST-TbU1-70K, followed by GST pull-down. For each reaction, 10% of the input () and the total precipitated material () were analyzed. , P-labeled pBR322/HpaII markers. () Sequences and proposed secondary structures of the U1 snRNA and its mutant derivatives. The boxed sequence in the U1 snRNA indicates the Sm site; the two arrows indicate a potential second stem–loop. Below, the sequences of the stem–loop derivatives are given; the circled nucleotides mark the two positions in the human loop that differ from the sequence, and the single-nucleotide mutation (A21) in the mutant human loop

Protein–protein interactions in the trypanosome U1 snRNP: TbU1-70K interacts with both TbU1C and TbU1-24K

<p><b>Copyright information:</b></p><p>Taken from "U1 small nuclear RNP from : a minimal U1 snRNA with unusual protein components"</p><p>Nucleic Acids Research 2005;33(8):2493-2503.</p><p>Published online 29 Apr 2005</p><p>PMCID:PMC1087902.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> () GST-fusion proteins of TbU1C, TbU1-24K and TbU1-70K, as well as GST alone as a control were immobilized on glutathione-Sepharose. Corresponding aliquots of immobilized proteins were analyzed for their protein content by SDS–PAGE and Coomassie staining. The arrows point to the proteins listed above the lanes. , protein marker (in kDa). () Immobilized GST proteins (as indicated above the lanes) were incubated with S-labeled TbU1C (lanes 1–4), TbU1-24K (lanes 5–8) or TbU1-70K (lanes 9–12). After washing, bound proteins were recovered and analyzed by SDS–PAGE and fluorography. The arrows point to the respective S-labeled proteins

U1C (TbU1C): a U1 snRNP-specific component binding specifically to the 5′ terminal sequence of U1 snRNA

<p><b>Copyright information:</b></p><p>Taken from "U1 small nuclear RNP from : a minimal U1 snRNA with unusual protein components"</p><p>Nucleic Acids Research 2005;33(8):2493-2503.</p><p>Published online 29 Apr 2005</p><p>PMCID:PMC1087902.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> () ClustalW alignment of the protein sequences for the newly identified U1C homologs from , and , in comparison with the human U1C sequence. The conserved CH-type Zn finger within the boxed sequence is highlighted by large-size letters; asterisks indicate absolutely conserved amino acid positions. Accession numbers (GeneDB): (Tb10.70.5640), (Tc00.1047053511367.354) and (LmjF21.0320); human U1C (P09234). () Extract was prepared from a cell line, which stably expresses TAP-tagged TbU1C protein, and used to affinity-purify TAP-tagged complexes. Purification was followed by analyzing copurifying RNAs by northern blotting, using a mixed snRNA probe (snRNA positions indicated on the right). , DIG marker V (Roche). Lane 1, 1% of input; lane 2, 10% of IgG-selected and TEV-released material. Affinity-purified complexes were then immunoprecipitated with NIS (lane 3), anti TbU1-70K (lane 4) or anti-Sm antibodies (lane 5), using 30% for each immunoprecipitation. () TbU1C protein binds specifically to the 5′ terminal sequence of U1 snRNA. GST TbU1C protein was incubated with P-labeled full-length U1 snRNA (lanes 1 and 2) and various U1 snRNA derivatives: U1 Δstem–loop (lanes 3 and 4), U1 Δ5′(1–14) (lanes 5, 6), U1 Δ5′(1–30) (lanes 7 and 8), U1 5′ stem–loop (lanes 9 and 10), U1 5′(1–14) (lanes 11 and 12) or a 17mer control RNA (lanes 13 and 14). In each case, 10% of the input () and the total GST pull-down material () were analyzed