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Anneli Ritala Kristian Aspegren Ulrika Kurtén Marjatta Salmenkallio-Marttila Leena Mannonen Riitta Hannus Veli Kauppinen Teemu H. Teeri Tor-Magnus Enari 《Plant molecular biology》1994,24(2):317-325
Transgenic, fertile barley (Hordeum vulgare L.) from the Finnish elite cultivar Kymppi was obtained by particle bombardment of immature embryos. Immature embryos were bombarded to the embryonic axis side and grown to plants without selection. Neomycin phosphotransferase II (NPTII) activity was screened in small plantlets. One out of a total of 227 plants expressed the transferred nptII gene. This plant has until now produced 98 fertile spikes (T0), and four of the 90 T0 spikes analyzed to date contained the nptII gene. These shoots were further analyzed and they expressed the transferred gene. From green grains, embryos were isolated and grown to plantlets (T1). The four transgenic shoots of Toivo (the T0 plant) produced 25 plantlets as T1 progeny. Altogether fifteen of these T1 plants carried the transferred nptII gene as detected with the PCR technique, fourteen of which expressed the nptII gene. The integration and inheritance of the transferred nptII gene was confirmed by Southern blot hybridization. Although present as several copies, the transferred gene was inherited as a single Mendelian locus into the T2 progeny. 相似文献
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Kerli Mooses Jarek M?estu Eva-Maria Riso Aave Hannus Martin Mooses Priit Kaasik Merike Kull 《PloS one》2016,11(3)
Introduction
The aim was to compare the average and the days method in exploring the compliance of children with physical activity guidelines and describe their physical activity patterns in different school day segments.Methods
Physical activity was objectively measured in 472 children aged 6–13 for one school week. Children were compliant when fulfilling PA recommendations 1) on average over all measured days (average method) or 2) on at least four measured days (days method). To explore the difference in moderate to vigorous physical activity (MVPA) minutes between compliant and non-complaint children (using both the average and days method) in various day segments, linear mixed models was used.Results
Compliance with physical activity guidelines was significantly higher with the average compared to the days method (51.7% and 23.7%, respectively). In segmented-day analysis, compliant children accrued more MVPA minutes in all day segments, especially during after-school. Gender differences appeared only during the in-school segments, where girls spent less time in MVPA (average method: -4.39 min, 95% CI = -5.36,-3.42, days method: -4.45 min, 95%CI = -5.46,-3.44). Older children accrued more MVPA minutes during physical education classes, but less during breaks, compared to younger children.Conclusions
The used methods yielded remarkably different prevalence estimates for compliance to physical activity recommendations. To ensure comparability between studies, interventions and reports, there is a need for internationally agreed operationalization and assessment methods of physical activity guidelines. As non-compliant children had lower MVPA during all day segments, greater efforts should be made to provide physical activity opportunities both during and after school. 相似文献3.
Structure and Evolution of the Archaeal Lipid Synthesis Enzyme sn-Glycerol-1-phosphate Dehydrogenase
Vincenzo Carbone Linley R. Schofield Yanli Zhang Carrie Sang Debjit Dey Ingegerd M. Hannus William F. Martin Andrew J. Sutherland-Smith Ron S. Ronimus 《The Journal of biological chemistry》2015,290(35):21690-21704
One of the most critical events in the origins of cellular life was the development of lipid membranes. Archaea use isoprenoid chains linked via ether bonds to sn-glycerol 1-phosphate (G1P), whereas bacteria and eukaryotes use fatty acids attached via ester bonds to enantiomeric sn-glycerol 3-phosphate. NAD(P)H-dependent G1P dehydrogenase (G1PDH) forms G1P and has been proposed to have played a crucial role in the speciation of the Archaea. We present here, to our knowledge, the first structures of archaeal G1PDH from the hyperthermophilic methanogen Methanocaldococcus jannaschii with bound substrate dihydroxyacetone phosphate, product G1P, NADPH, and Zn2+ cofactor. We also biochemically characterized the enzyme with respect to pH optimum, cation specificity, and kinetic parameters for dihydroxyacetone phosphate and NAD(P)H. The structures provide key evidence for the reaction mechanism in the stereospecific addition for the NAD(P)H-based pro-R hydrogen transfer and the coordination of the Zn2+ cofactor during catalysis. Structure-based phylogenetic analyses also provide insight into the origins of G1PDH. 相似文献
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Ed Hurt Stefan Hannus Birgit Schmelzl Denise Lau David Tollervey George Simos 《The Journal of cell biology》1999,144(3):389-401
To identify components involved in the nuclear export of ribosomes in yeast, we developed an in vivo assay exploiting a green fluorescent protein (GFP)-tagged version of ribosomal protein L25. After its import into the nucleolus, L25-GFP assembles with 60S ribosomal subunits that are subsequently exported into the cytoplasm. In wild-type cells, GFP-labeled ribosomes are only detected by fluorescence in the cytoplasm. However, thermosensitive rna1-1 (Ran-GAP), prp20-1 (Ran-GEF), and nucleoporin nup49 and nsp1 mutants are impaired in ribosomal export as revealed by nuclear accumulation of L25-GFP. Furthermore, overexpression of dominant-negative RanGTP (Gsp1-G21V) and the tRNA exportin Los1p inhibits ribosomal export. The pattern of subnuclear accumulation of L25-GFP observed in different mutants is not identical, suggesting that transport can be blocked at different steps. Thus, nuclear export of ribosomes requires the nuclear/cytoplasmic Ran-cycle and distinct nucleoporins. This assay can be used to identify soluble transport factors required for nuclear exit of ribosomes. 相似文献
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Meister G Hannus S Plöttner O Baars T Hartmann E Fakan S Laggerbauer B Fischer U 《The EMBO journal》2001,20(9):2304-2314
SMNrp, also termed SPF30, has recently been identified in spliceosomes assembled in vitro. We have functionally characterized this protein and show that it is an essential splicing factor. We show that SMNrp is a 17S U2 snRNP-associated protein that appears in the pre-spliceosome (complex A) and the mature spliceosome (complex B) during splicing. Immunodepletion of SMNrp from nuclear extract inhibits the first step of pre-mRNA splicing by preventing the formation of complex B. Re-addition of recombinant SMNrp to immunodepleted extract reconstitutes both spliceosome formation and splicing. Mutations in two domains of SMNrp, although similarly deleterious for splicing, differed in their consequences on U2 snRNP binding, suggesting that SMNrp may also engage in interactions with splicing factors other than the U2 snRNP. In agreement with this, we present evidence for an additional interaction between SMNrp and the [U4/U6.U5] tri-snRNP. A candidate that may mediate this interaction, namely the U4/U6-90 kDa protein, has been identified. We suggest that SMNrp, as a U2 snRNP-associated protein, facilitates the recruitment of the [U4/U6.U5] tri-snRNP to the pre-spliceosome. 相似文献
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Daniel Schraivogel Susann G. Schindler Johannes Danner Elisabeth Kremmer Janina Pfaff Stefan Hannus Reinhard Depping Gunter Meister 《Nucleic acids research》2015,43(15):7447-7461
MicroRNAs (miRNAs) guide Argonaute (Ago) proteins to distinct target mRNAs leading to translational repression and mRNA decay. Ago proteins interact with a member of the GW protein family, referred to as TNRC6A-C in mammals, which coordinate downstream gene-silencing processes. The cytoplasmic functions of TNRC6 and Ago proteins are reasonably well established. Both protein families are found in the nucleus as well. Their detailed nuclear functions, however, remain elusive. Furthermore, it is not clear which import routes Ago and TNRC6 proteins take into the nucleus. Using different nuclear transport assays, we find that Ago as well as TNRC6 proteins shuttle between the cytoplasm and the nucleus. While import receptors might function redundantly to transport Ago2, we demonstrate that TNRC6 proteins are imported by the Importin-β pathway. Finally, we show that nuclear localization of both Ago2 and TNRC6 proteins can depend on each other suggesting actively balanced cytoplasmic Ago – TNRC6 levels. 相似文献
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During planar polarization of the Drosophila wing epithelium, the homophilic adhesion molecule Flamingo localizes to proximal/distal cell boundaries in response to Frizzled signaling; perturbing Frizzled signaling alters Flamingo distribution, many cell diameters distant, by a mechanism that is not well understood. This work identifies a tissue polarity gene, diego, that comprises six ankyrin repeats and colocalizes with Flamingo at proximal/distal boundaries. Diego is specifically required for polarized accumulation of Flamingo and drives ectopic clustering of Flamingo when overexpressed. Our data suggest that Frizzled acts through Diego to promote local clustering of Flamingo, and that clustering of Diego and Flamingo in one cell nonautonomously propagates to others. 相似文献