Aneta Sabovljevic

The Arabidopsis elch mutant reveals functions of an ESCRT component in cytokinesis

Recently, an alternative route to the proteasomal protein-degradation pathway was discovered that specifically targets transmembrane proteins marked with a single ubiquitin to the endosomal multivesicular body (MVB) and, subsequently, to the vacuole (yeast) or lysosome (animals), where they are degraded by proteases. Vps23p/TSG101 is a key component of the ESCRT I-III machinery in yeast and animals that recognizes mono-ubiquitylated proteins and sorts them into the MVB. Here, we report that the Arabidopsis ELCH (ELC) gene encodes a Vps23p/TSG101 homolog, and that homologs of all known ESCRT I-III components are present in the Arabidopsis genome. As with its animal and yeast counterparts, ELC binds ubiquitin and localizes to endosomes. Gel-filtration experiments indicate that ELC is a component of a high-molecular-weight complex. Yeast two-hybrid and immunoprecipitation assays showed that ELC interacts with Arabidopsis homologs of the ESCRT I complex. The elc mutant shows multiple nuclei in various cell types, indicating a role in cytokinesis. Double-mutant analysis with kaktus shows that increased ploidy levels do not influence the cytokinesis effect of elc mutants, suggesting that ELC is only important during the first endoreduplication cycle. Double mutants with tubulin folding cofactor a mutants show a synergistic phenotype, suggesting that ELC regulates cytokinesis through the microtubule cytoskeleton.

The AAA‐type ATPase AtSKD1 contributes to vacuolar maintenance of Arabidopsis thaliana

The vacuole is the most prominent organelle of plant cells. Despite its importance for many physiological and developmental aspects of plant life, little is known about its biogenesis and maintenance. Here we show that Arabidopsis plants expressing a dominant-negative version of the AAA (ATPase associated with various cellular activities) ATPase AtSKD1 (SUPPRESSOR OF K+ TRANSPORT GROWTH DEFECT1) under the control of the trichome-specific GLABRA2 (GL2) promoter exhibit normal vacuolar development in early stages of trichome development. Shortly after its formation, however, the large central vacuole is fragmented and finally disappears completely. Secretion assays with amylase fused to the vacuolar sorting signal of Sporamin show that dominant-negative AtSKD1 inhibits vacuolar trafficking of the reporter that is instead secreted. In addition, trichomes expressing dominant-negative AtSKD1 frequently contain multiple nuclei. Our results suggest that AtSKD1 contributes to vacuolar protein trafficking and thereby to the maintenance of the large central vacuole of plant cells, and might play a role in cell-cycle regulation.

The Arabidopsis ESCRT protein–protein interaction network

In yeast, endosomal sorting of monoubiquitylated transmembrane proteins is performed by a subset of the 19 “class E vacuolar protein sorting” proteins. The core machinery consists of 11 proteins that are organised in three complexes termed ESCRT I-III (endosomal sorting complex required for transport I-III) and is conserved in eukaryotic cells. While the pathway is well understood in yeast and animals, the plant ESCRT system is largely unexplored. At least one sequence homolog for each ESCRT component can be found in the Arabidopsis genome. Generally, sequence conservation between yeast/animals and the Arabidopsis proteins is low. To understand details about participating proteins and complex organization we have performed a systematic pairwise yeast two hybrid analysis of all Arabidopsis proteins showing homology to the ESCRT core machinery. Positive interactions were validated using bimolecular fluorescence complementation. In our experiments, most putative ESCRT components exhibited interactions with other ESCRT components that could be shown to occur on endosomes suggesting that despite their low homology to their yeast and animal counterparts they represent functional components of the plant ESCRT pathway.

New national and regional bryophyte records, 39

New national and regional bryophyte records, 39 L. T. Ellis, O. M. Afonina, A. K. Asthana, R. Gupta, V. Sahu, V. Nath, N. Batan, H. Bednarek-Ochyra, A. Benitez, P. Erzberger, V. E. Fedosov, P. Gorski, S. R. Gradstein, N. Gremmen, T. Hallingback, M. Hagstrom, H. Kockinger, M. Lebouvier, L. Meinunger, C. Nemeth, M. Nobis, A. Nowak, T. Ozdemir, J. Pantovic, A. Sabovljevic, M. S. Sabovljevic, P. Pawlikowski, V. Plasek, L. Cihal, J. Sawicki, C. Sergio, P. Ministro, C. A. Garcia, V. R. Smith, S. Ştefănuţ, S. Stow, G. M. Suarez, J. R. Flores, L. Thouvenot, J. Vaňa, J. van Rooy, R. H. Zander Department of Life Sciences, The Natural History Museum, London, U.K., V.L. Komarov Botanical Institute, Saint Petersburg, Russia, Bryology Laboratory, National Botanical Research Institute, Lucknow, India, Macka Vocational School, Karadeniz Technical University, Trabzon, Turkey, Laboratory of Bryology, Institute of Botany, Polish Academy of Sciences, Poland, Universidad Tecnica Particular de Loja, Departamento de Ciencias Naturales, Loja, Ecuador, Berlin, Germany, M.V. Lomonosov Moscow State University, Russia, Department of Botany, Poznan University of Life Sciences, Poland, Museum National d’Histoire Naturelle, Department Systematique et Evolution, Paris, France, Hesselstraat 11, 7981 CD Diever, The Netherlands, Swedish University of Agricultural Sciences, Species Information Centre, Uppsala, Sweden, Roseggergasse 12, Weisskirchen, Austria, CNRS UMR 6553, Universite de Rennes 1, France, Ludwigsstadt, Germany, Corvinus University Budapest, Department of Horticultural Sciences, Hungary, Jagiellonian University in Krakow, Poland, University of Opole, Poland, Department of Biology, Karadeniz Technical University, Trabzon, Turkey, Institute of Botany and Botanical Garden, University of Belgrade, Serbia, Department of Plant Ecology and Environmental Conservation, Institute of Botany, University of Warsaw, Poland, University of Ostrava, Czech Republic, University of Warmia and Mazury in Olsztyn, Poland, Museu Nacional de Historia Natural e da Ciencia/Centro de Biologia Ambiental, Universidade de Lisboa, Portugal, Department of Botany, University of Stellenbosch, Republic of South Africa, Institute of Biology of Bucharest Romanian Academy, Romania, Durrell Institute of Conservation & Ecology, School of Anthropology & Conservation, University of Kent, Canterbury, U.K., Facultad de Ciencias Naturales, U.N.T., San Miguel de Tucuman, Argentina, 11 rue Saint Leon, Perpignan, France, 30 Department of Botany, Charles University, Czech Republic, National Herbarium, South African National Biodiversity Institute, Pretoria, South Africa, Missouri Botanical Garden, St. Louis, USA

New national and regional bryophyte records, 36

ub lis he d by M an ey P ub lis hi ng ( c) B rit is h B ry ol og ic al S oc ie ty Bryological Notes New national and regional bryophyte records, 36 L T Ellis, V A Bakalin, E Baisheva, H Bednarek-Ochyra, R Ochyra, E A Borovichev, S S Choi, B-Y Sun, P Erzberger, V E Fedosov, R Garilleti, B Albertos, P Gorski, P Hajkova, N G Hodgetts, M Ignatov, A Koczur, L E Kurbatova, M Lebouvier, A Mežaka, J Miravet, P Pawlikowski, R D Porley, J A Rossello, M S Sabovljevic, J Pantovic, A Sabovljevic, W Schroder, S Ştefănuţ, G M Suarez, M Schiavone, O T Yayintas, J Vaňa The Natural History Museum, London, UK, Botanical Garden-Institute, Vladivostok, Russia, Institute of Biology and Soil Science, Vladivostok, Russia, Institute of Biology of Ufa, Scientific Centre of Russian Academy of Sciences, Ufa, Russia, Institute of Botany, Poland, Polar-Alpine Botanical Garden-Institute, Kirovsk, Russia, Chonbuk National University, Jeonju, Korea, Berlin, Germany, M.V. Lomonosov Moscow State University, Russia, Universidad de Valencia, Burjassot, Spain, Poznan University of Life Sciences, Poland, Masaryk University, Brno, Czech Republic, Institute of Botany, Brno, Czech Republic, Earlish, Isle of Skye, UK, Main Botanical Garden, Moscow, Russia, Institute of Nature Conservation, Krakow, Poland, Komarov Botanical Institute, Russia, Universite de Rennes 1, France, University of Latvia, Riga, Latvia, Marimurtra Botanical Garden, Catalonia, Spain, University of Warsaw, Poland, Cerca dos Pomares, Portugal, Universidad de Valencia, Spain, University of Belgrade, Serbia, Ludwigsstadt, Germany, Institute of Biology of Romanian Academy, Bucharest, Romania, Facultad de Ciencias Naturales e I.M.L., Tucuman, Argentina, Canakkale Onsekiz Mart University, Biga, Canakkale, Turkey, Charles University, Praha, Czech Republic

In Vitro Culture and Secondary Metabolite Isolation in Bryophytes

Bryophytes, the second largest group of land plants, are extremely rich in terpenoids, phenols, glycosides, and fatty acids. Although bryophytes could be used in medicine, their chemistry is not very well known and the problem remains to obtain enough quantity of same species for analysis. In vitro cultivation of bryophytes is the most appropriate way for large biomass production and isolate of numerous useful compounds showing some interesting biologic activities. This technique is also useful in developmental, cellular, molecular, biochemical, and eco-physiologic studies.

New national and regional bryophyte records, 42

New national and regional bryophyte records, 42 L. T. Ellis, M. Aleffi, V. A. Bakalin, H. Bednarek-Ochyra, A. Bergamini, P. Beveridge, S. S. Choi, V. E. Fedosov, R. Gabriel, M. T. Gallego, S. Grdović, R. Gupta, V. Nath, A. K. Asthana, L. Jennings, H. Kürschner, M. Lebouvier, M. C. Nair, K. M. Manjula, K. P. Rajesh, M. Nobis, A. Nowak, S. J. Park, B.-Y. Sun, V. Plášek, L. Čı́hal, S. Poponessi, M. G. Mariotti, A. Sabovljević, M. S. Sabovljević, J. Sawicki, N. Schnyder, R. Schumacker, M. Sim-Sim, D. K. Singh, D. Singh, S. Majumdar, S. Singh Deo, S. Ştefănuţ, M. Suleiman, C. M. Seng, M. S. Chua, J. Váňa, R. Venanzoni, E. Bricchi, M. J. Wigginton Department of Life Sciences, The Natural History Museum, London, UK, University of Camerino, Camerino (MC), Italy, Botanical Garden-Institute, Vladivostok, Russia, Laboratory of Bryology, Institute of Botany, Polish Academy of Sciences, Poland, Swiss Federal Research Institute WSL, Biodiversity & Conservation Biology, Birmensdorf, Switzerland, Museum of New Zealand Te Papa Tongarewa, Wellington, New Zealand, National Institute of Ecology, Seocheon, Korea, M.V. Lomonosov Moscow State University, Russia, Azorean Biodiversity Group — CITAA, DCA — University of the Azores, Portugal, Departamento de Biologı́a Vegetal (Botánica), Universidad de Murcia, Spain, Faculty of Veterinary Medicine, University of Belgrade, 11000 Belgrade, Serbia, CSIR-National Botanical Research Institute, Lucknow, India, Conservation Biogeography and Macroecology Group, SGE — University of Oxford, UK, Freie Universität Berlin, Institut für Biologie, Systematische Botanik und Pflanzengeographie, Germany, CNRS UMR 6553, Université de Rennes 1, France, Department of Botany, The Zamorin’s Guruvayurappan College, Kozhikode, Kerala, India, Jagiellonian University in Kraków, Poland, University of Opole, Poland, Department of Life Sciences, Chonbuk National University, Jeonju, Korea, University of Ostrava, Czech Republic, University of Genova, Genova, Italy, Institute of Botany and Botanical Garden, University of Belgrade, Serbia, University of Warmia and Mazury in Olsztyn, Poland, Institut für Systematische Botanik, Universität Zürich, Switzerland, Department of Botany, University of Liège, Belgium, Centre for Environmental Biology, University of Lisbon, Portugal, Botanical Survey of India, Kolkata, India, Botanical Survey of India, Central National Herbarium, Howrah, India, Institute of Biology Bucharest of Romanian Academy, Romania, Institute for Tropical Biology and Conservation, University Malaysia, Sabah, Malaysia, Department of Botany, Charles University, Czech Republic, University of Perugia, Italy, Warmington, Peterborough, UK

New national and regional bryophyte records, 46

L. T. Ellis1, A. K. Asthana2, P. Srivastava2, I. Omar2, K. K. Rawat2, V. Sahu2, M. J. Cano3, D. P. Costa4, E. M. Dias5,8, N. Dias dos Santos5,6, J. B. Silva5, V. E. Fedosov7, M. N. Kozhin7, E. A. Ignatova7, S. R. Germano8, E. O. Golovina9, N. J. M. Gremmen10, R. Ion11, S. Ştefǎnuţ11, M. von Konrat12, M. S. Jimenez13,14, G. M. Suárez13,15, T. Kiebacher16, M. Lebouvier17, D. G. Long18, D. Maity19, R. Ochyra20, I. Parnikoza21, V. Plášek22, L. Fialová22, Z. Skoupá22, S. Poponessi23, M. Aleffi23, M. S. Sabovljević24, A. D. Sabovljević24, P. Saha25, M. N. Aziz25, J. Sawicki26,22, M. Suleiman27, B.-Y. Sun28, J. Váňa29, T. Wójcik30, Y.-J. Yoon31, J. Żarnowiec32, J. Larraín33

New national and regional bryophyte records, 48

Andreaea rothii has been recorded for the first time in Croatia. It is a boreo-temperate suboceanic species (Hill et al., 2007) relatively rare in SE Europe, since it is known only from Romania (Ellis et al., 2014d), Slovenia and Serbia (Sabovljevic´ et al., 2008 ; Hodgetts, 2015). The species was found in the Papuk Mountains, situated in the mainly lowland area of NE Croatia. In this region Papuk is the largest and highest mountain range, with peaks between 800 and 900 m a.s.l. They are characterized by high geological diversity dominated by metamorphic rocks, such as different types of schists, as well as granites. The climate is temperate, moderately warm without an explicit dry period. About 60% of the almost totally forested area is covered by different communities of beech forests. The well-developed black patches of A. rothii cover an area ca 2 m× 0.5 m on a steep north-facing cliff on the edge of an acidothermophilic sessile oak (Quercus petraea agg.) forest. The specimens of A. rothii grew on the bare rock with the following bryophyte species: Cynodontium polycarpon (Hedw.) Schimp., Dicranella heteromalla (Hedw.) Schimp., Dicranum scoparium Hedw., Polytrichum piliferum Schreb. ex Hedw. and Rhabdoweisia (cf.) fugax (Hedw.) Bruch & Schimp. The population is very small with an extremely high risk of extinction, therefore we propose CR as Red List status for the taxon in Croatia. According to the last checklist of the moss flora of Croatia (Sabovljevic´, 2006), only Andreaea rupestris Hedw., collected from just one locality in 1927 (Horvat, 1932 and ZA), was reported for the genus. The locality is very interesting from the point of view of the vegetation of Croatia, because it is within 100 m of the second stand of Fagus sylvatica L.-Sphagnum quinquefarium (Braithw.) Warnst. forest (Alegro et al., 2015). The second occurrence of Dicranum spurium Hedw. (Ellis et al., 2014d) and Rhabdoweisia fugax (Papp et al., 2013) in Croatia are also found here. Another interesting moss is S. capillifolium (Ehrh.) Hedw., that forms small red patches within the thick carpets of S. quinquefarium under the open oulder scree forest in the neighbourhood.

Secoiridoid content of Blackstonia perfoliata in vivo and in vitro

SummaryThis study reports the analysis of secondary metabolites of gentiopicrin, swertiamarin, and sweroside in shoot and root cultures of yellow wort (Blackstonia perfoliata), which were initiated from seeds, grown on Murashige and Skoog (MS) medium. Shoot cultures of B. perfoliata were inoculated with suspension of Agrobacterium rhizogenes strain A4M70GUS and hairy roots appeared at the infected sites after 3 wk of inoculation. Tips of adventitious roots of B. perfoliata were grown on hormone-free MS medium and three clones of the transformed roots regenerated shoots spontaneously. Gentiopicrin, swertiamarin, and sweroside were detected in both roots and shoots of B. perfoliata in vitro and in vivo, but gentiopicrin was found to be the major compound. The concentration of growth regulator in the medium affected the production of secoiridoids in B. perfoliata in vitro, where the level of gentiopicrin was higher in plants grown in the presence of indole-3-butyric acid, but the presence of 6-benzylaminopurine was inhibitory to secoiridoid production.