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71.
Susan Fischer Juliane Benz Bettina Sp?th Lisa-Katharina Maier Julia Straub Michaela Granzow Monika Raabe Henning Urlaub Jan Hoffmann Bernd Brutschy Thorsten Allers J?rg Soppa Anita Marchfelder 《The Journal of biological chemistry》2010,285(45):34429-34438
Proteins of the Lsm family, including eukaryotic Sm proteins and bacterial Hfq, are key players in RNA metabolism. Little is known about the archaeal homologues of these proteins. Therefore, we characterized the Lsm protein from the haloarchaeon Haloferax volcanii using in vitro and in vivo approaches. H. volcanii encodes a single Lsm protein, which belongs to the Lsm1 subfamily. The lsm gene is co-transcribed and overlaps with the gene for the ribosomal protein L37e. Northern blot analysis shows that the lsm gene is differentially transcribed. The Lsm protein forms homoheptameric complexes and has a copy number of 4000 molecules/cell. In vitro analyses using electrophoretic mobility shift assays and ultrasoft mass spectrometry (laser-induced liquid bead ion desorption) showed a complex formation of the recombinant Lsm protein with oligo(U)-RNA, tRNAs, and an small RNA. Co-immunoprecipitation with a FLAG-tagged Lsm protein produced in vivo confirmed that the protein binds to small RNAs. Furthermore, the co-immunoprecipitation revealed several protein interaction partners, suggesting its involvement in different cellular pathways. The deletion of the lsm gene is viable, resulting in a pleiotropic phenotype, indicating that the haloarchaeal Lsm is involved in many cellular processes, which is in congruence with the number of protein interaction partners. 相似文献
72.
Kremser ME Przybyło M Hoja-Łukowicz D Pocheć E Amoresano A Carpentieri A Bubka M Lityńska A 《Biochimica et biophysica acta》2008,1780(12):1421-1431
It is well documented that glycan synthesis is altered in some pathological processes, including cancer. The most frequently observed alterations during tumourigenesis are extensive expression of beta1,6-branched complex type N-glycans, the presence of poly-N-acetyllactosamine structures, and high sialylation of cell surface glycoproteins. This study investigated two integrins, alpha3beta1 and alpha(v)beta3, whose expression is closely related to cancer progression. Their oligosaccharide structures in two metastatic melanoma cell lines (WM9, WM239) were analysed with the use of matrix-assisted laser desorption ionisation mass spectrometry. Both examined integrins possessed heavily sialylated and fucosylated glycans, with beta1,6-branches and short polylactosamine chains. In WM9 cells, alpha3beta1 integrin was more variously glycosylated than alpha(v)beta3; in WM239 cells the situation was the reverse. Functional studies (wound healing and ELISA integrin binding assays) revealed that the N-oligosaccharide component of the tested integrins influenced melanoma cell migration on vitronectin and alpha3beta1 integrin binding to laminin-5. Additionally, more variously glycosylated integrins exerted a stronger influence on these parameters. To the best of our knowledge, this is the first report concerning structural characterisation of alpha(v)beta3 integrin glycans in melanoma or in any cancer cells. 相似文献
73.
Jan Plue Pieter De Frenne Kamal Acharya Jrg Brunet Olivier Chabrerie Guillaume Decocq Martin Diekmann Bente J. Graae Thilo Heinken Martin Hermy Annette Kolb Isgard Lemke Jaan Liira Tobias Naaf Anna Shevtsova Kris Verheyen Monika Wulf Sara A. O. Cousins 《Global Ecology and Biogeography》2013,22(10):1106-1117
74.
Ruth Graf Monika Meyer-Holzapfel 《Ethology : formerly Zeitschrift fur Tierpsychologie》1974,35(3):320-332
An 11 Versuchstagen wurden die Reaktionen von insgesamt 3 Rüden und 2 Hündinnen auf einem rund 2stündigen Spaziergang in nicht oder wenig bekanntem Gebiet beobachtet. Auf einem ersten Rundgang wurden die spontan abgegebenen Harnmarken eines Versuchstieres mit kleinen Objekten markiert, dann ein zweiter Hund an loser Leine den gleichen Weg (meist in umgekehrter Richtung) entlanggeführt und dessen Reaktionen auf die markierten Stellen registriert. Im ganzen wurden bei den ersten Rundgängen 261 Harnmarken abgesetzt. In 47,1 % der Fälle ging der im zweiten Rundgang vorbeigeführte Hund ohne ersichtlichen Grund an der Harnmarke vorbei. Bei Beachtung der Marken zeigten sich 6 verschiedene Reaktionen: 1. Beschnuppern, 2. Harnen über oder neben die Marke, 3. Scharren mit den Hinterpfoten nach Überharnen, 4. Belecken der Marke, 5. Knurren beim Scharren, 6. Zähneklappern nach Beschnuppern und Belecken. Die Marken von feindlichen Rüden und läufigen Hündinnen werden nach Beschnuppern signifikant häufiger als die eigenen bzw. diejenigen einer nichtläufigen Hündin mit einer weiteren Reaktion beantwortet. Die Marken nichtläufiger Hündinnen und die eigenen Marken ergaben keine unterschiedlichen Reaktionen beim Rüden. Eine Hündin reagiert auf die Marken eines (feindl.) Rüden nicht mehr als ein Rüde auf die eigenen Marken. Die Harnmarken vermitteln dem Hunderüden Informationen darüber, ob sie von einer läufigen Hündin, einem fremden Rüden oder von ihm selbst (bzw. einer nicht-läufigen Hündin) stammen. 相似文献
75.
76.
Jain Surbhi Paliwal Ayushi Gupta Vinay Tomar Monika 《Plasmonics (Norwell, Mass.)》2020,15(4):1091-1101
Plasmonics - The present study focuses on the employment of TiO2 (titanium dioxide) film as an anti-reflective coating (ARC) on thin crystalline silicon (Si)-based solar cells along with the... 相似文献
77.
78.
Does operational sex ratio influence relative strength of purging selection in males versus females?
Agata Plesnar‐Bielak Karolina Sychta Tomasz S. Gaczorek Joanna K. Palka Monika A. Prus Zofia M. Prokop 《Journal of evolutionary biology》2020,33(1):80-88
According to theory, sexual selection in males may efficiently purge mutation load of sexual populations, reducing or fully compensating ‘the cost of males’. For this to occur, mutations not only need to be deleterious to both sexes, they also must affect males more than females. A frequently overlooked problem is that relative strength of selection on males versus females may vary between environments, with social conditions being particularly likely to affect selection in males and females differently. Here, we induced mutations in red flour beetles (Tribolium castaneum) and tested their effect in both sexes under three different operational sex ratios (1:2, 1:1 and 2:1). Induced mutations decreased fitness of both males and females, but their effect was not stronger in males. Surprisingly, operational sex ratio did not affect selection against deleterious mutations nor its relative strength in the sexes. Thus, our results show no support for the role of sexual selection in the evolutionary maintenance of sex. 相似文献
79.
Abdullah Mohib Sliwinska Elwira Góralski Grzegorz Latocha Piotr Tuleja Monika Widyna Patrycja Popielarska-Konieczna Marzena 《Plant Cell, Tissue and Organ Culture》2021,147(3):569-582
Plant Cell, Tissue and Organ Culture (PCTOC) - Endosperm, an ephemeral and storage tissue, serves as a source of nutrition and protection during embryo development and germination. It can be used... 相似文献
80.
Cioch-Skoneczny Monika Satora Paweł Skoneczny Szymon Skotniczny Magdalena 《Archives of microbiology》2021,203(1):153-162
Archives of Microbiology - Biodiversity of native yeasts, especially in winemaking, has hidden potential. In order to use the value of non-Saccharomyces strains in wine production and to minimise... 相似文献