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High levels of variability were observed in tissue cultured Gaura lindheimeri genotypes when flowered in situ. Tissue culture treatments for chromosome doubling (colchicine: 0, 0.25, 1.25 mM; trifluralin:
0, 15, 30 μM) were all highly variable for morphological traits. Experiment No. 1 tested the tissue culture protocols used.
In the first control (C1), plantlets were subcultured continuously. Nodes were excised and placed on solid medium for the
second control (C2). In the third control (C3), nodes were excised and put in liquid medium for 24 h at room temperature.
The fourth control (C4) was the same as the third control except liquid cultures were moved to 4°C for 48 h after treatment
at room temperature. Experiment No. 2 examined the stability of the variation. Representative plants with different traits
were selected for clonal propagation and grown in a replicated trial in the greenhouse. Several morphological traits (flower
size, leaf length:width ratios, petal length:width ratios, and flower color) were measured. All of the controls had as much
variability as the treated plants. Flower size of the first flower for plant number 01G-02 was significantly different in
C1 compared with C3, but not with C2 and C4. Plant number 443-1 (white) was more stable in the replicated trial for the flower
size than plant number 01G-02 (pink). All traits measured for plant number 01G-02 were unstable; most flower colors and patterns
reverted back to the original color of the non-tissue cultured plants. The somaclonal variation observed was epigenetic in
nature, indicating changes in DNA methylation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Jennifer Hochscherf Dirk Lindenblatt Michaela Steinkrüger Eungyoung Yoo Özlem Ulucan Stefan Herzig Olaf-Georg Issinger Volkhard Helms Claudia Götz Ines Neundorf Karsten Niefind Markus Pietsch 《Analytical biochemistry》2015
Increased activity of protein kinase CK2 is associated with various types of cancer, neurodegenerative diseases, and chronic inflammation. In the search for CK2 inhibitors, attention has expanded toward compounds disturbing the interaction between CK2α and CK2β in addition to established active site-directed approaches. The current article describes the development of a fluorescence anisotropy-based assay that mimics the principle of CK2 subunit interaction by using CK2α1–335 and the fluorescent probe CF-Ahx-Pc as a CK2β analog. In addition, we identified new inhibitors able to displace the fluorescent probe from the subunit interface on CK2α1–335. Both CF-Ahx-Pc and the inhibitors I-Pc and Cl-Pc were derived from the cyclic peptide Pc, a mimetic of the C-terminal CK2α-binding motif of CK2β. The design of the two inhibitors was based on docking studies using the known crystal structure of the Pc/CK2α1–335 complex. The dissociation constants obtained in the fluorescence anisotropy assay for binding of all compounds to human CK2α1–335 were validated by isothermal titration calorimetry. I-Pc was identified as the tightest binding ligand with a KD value of 240 nM and was shown to inhibit the CK2 holoenzyme-dependent phosphorylation of PDX-1, a substrate requiring the presence of CK2β, with an IC50 value of 92 μM. 相似文献
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Katja?Witzel Christof?Pietsch Marc?Strickert Andrea?Matros Marion?S.?R?der Winfriede?Weschke Ulrich?Wobus Hans-Peter?MockEmail author 《Molecular breeding : new strategies in plant improvement》2011,27(3):301-314
Barley (Hordeum vulgare) is an important cereal crop grown for both the feed and malting industries. Hence, there is great interest to gain deeper
insight into the determinants of grain nutritional quality in order to improve the assessment of new traits. Two-dimensional
gel electrophoresis was employed for the characterization of the grain proteome of doubled-haploid introgression lines (IL)
representing a wild barley genome (Hordeum spontaneum Hs213) within a modern cultivar background (H. vulgare cv. Brenda). Proteome maps were subjected to differential cluster analysis and revealed ILs with similar or different protein
expression patterns compared to the Brenda parent. A total of 51 quantitative trait loci for protein expression (pQTL) were
detected, and proteins underlying these pQTL were further examined by mass spectrometry. Identification was successful for
49 of the segregating spots and functional annotation of proteins revealed that most proteins are involved in metabolism and
disease/defence-related processes. Among those, multigene families of glyceraldehyde-3-phosphate dehydrogenases, heat shock
proteins, peroxidases, and serpins were identified. Overall, eight pQTL signals were discovered in two independently grown
sets of plants. The mapped spots included protein disulfide isomerase, α-amylase inhibitor BDAI, NADP malic enzyme, adenosine
kinase and peroxidase BP1. Specific marker information of proteins involved in developmental events and protein storage as
well as in disease- and defence-related processes now allows for targeted breeding approaches to improve the grain quality
in barley. 相似文献
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Constanze Pietsch Juliane Hollender Falk Dorusch Patricia Burkhardt-Holm 《Cell biology and toxicology》2014,30(4):233-252
The worldwide distribution and high bioaccumulation potential of pentachlorophenol (PCP) in aquatic organisms imply a high toxicological impact in aquatic systems. Firstly, our investigations show that, similar to mammalian cell lines, PCP can be metabolized to tetrachlorohydroquinone (TCHQ) in the permanent cell line derived from rainbow trout liver cells (RTL-W1). Moreover, we demonstrate that PCP as well as its metabolite TCHQ is capable of influencing the viability of these cells. Three cell viability assays were performed to assess possible cellular targets of these substances. Thus, the cytotoxicity of the PCP-derivative TCHQ was shown for the first time in a fish cell line. Further investigations revealed the involvement of ROS in the cytotoxicity of PCP and its metabolite TCHQ. The observation of oxidative stress provides a plausible explanation for the increased cytotoxicity at higher concentrations especially for PCP and implies possible mechanisms underlying these observations. In addition, antioxidants such as ascorbic acid and quercetin modulate the detrimental effects of PCP and TCHQ whereby both compounds exacerbate the cytotoxic effects of high PCP and TCHQ concentrations. 相似文献
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Grosse J Wehland M Pietsch J Ma X Ulbrich C Schulz H Saar K Hübner N Hauslage J Hemmersbach R Braun M van Loon J Vagt N Infanger M Eilles C Egli M Richter P Baltz T Einspanier R Sharbati S Grimm D 《FASEB journal》2012,26(2):639-655
This study focused on the effects of short-term microgravity (22 s) on the gene expression and morphology of endothelial cells (ECs) and evaluated gravisensitive signaling elements. ECs were investigated during four German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt) parabolic flight campaigns. Hoechst 33342 and acridine orange/ethidium bromide staining showed no signs of cell death in ECs after 31 parabolas (P31). Gene array analysis revealed 320 significantly regulated genes after the first parabola (P1) and P31. COL4A5, COL8A1, ITGA6, ITGA10, and ITGB3 mRNAs were down-regulated after P1. EDN1 and TNFRSF12A mRNAs were up-regulated. ADAM19, CARD8, CD40, GSN, PRKCA (all down-regulated after P1), and PRKAA1 (AMPKα1) mRNAs (up-regulated) provide a very early protective mechanism of cell survival induced by 22 s microgravity. The ABL2 gene was significantly up-regulated after P1 and P31, TUBB was slightly induced, but ACTA2 and VIM mRNAs were not changed. β-Tubulin immunofluorescence revealed a cytoplasmic rearrangement. Vibration had no effect. Hypergravity reduced CARD8, NOS3, VASH1, SERPINH1 (all P1), CAV2, ADAM19, TNFRSF12A, CD40, and ITGA6 (P31) mRNAs. These data suggest that microgravity alters the gene expression patterns and the cytoskeleton of ECs very early. Several gravisensitive signaling elements, such as AMPKα1 and integrins, are involved in the reaction of ECs to altered gravity. 相似文献