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141.
Auxins or Sugars: What Makes the Difference in the Adventitious Rooting of Stored Carnation Cuttings? 总被引:1,自引:0,他引:1
Mar��a ��ngeles Agull��-Ant��n Jos�� S��nchez-Bravo Manuel Acosta Uwe Druege 《Journal of Plant Growth Regulation》2011,30(1):100-113
Cold storage of cuttings is frequently applied in the vegetative propagation of ornamental plants. Dianthus caryophyllus was used to study the limiting influences of auxin and sugars on adventitious root formation (ARF) in cuttings stored at
5°C. Carbohydrate levels during storage were modulated by exposing cuttings to low light or darkness. The resulting cuttings
were treated (or not) with auxin and planted, and then ARF was evaluated. Carbohydrate levels in the cuttings were monitored
and the influence of light treatment on indole-3-acetic acid (IAA) and zeatin (Z) in the basal stem was investigated. Dark
storage for up to 4 weeks increased the percentage of early rooted cuttings and the final number and length of adventitious
roots, despite decreased sugar levels in the stem base. Light during cold storage greatly enhanced sugar levels, particularly
in the stem base where the Z/IAA ratio was higher and ARF was lower than observed in the corresponding dark-stored cuttings.
Sugar levels in nonstored and dark-stored cuttings increased during the rooting period, and auxin application enhanced the
accumulation of sugars in the stem base of nonstored cuttings. Auxin stimulated ARF most strongly in nonstored, less so in
light-stored, and only marginally in dark-stored cuttings. A model of auxin-sugar interactions in ARF in carnation is proposed:
cold storage brings forward root induction and sink establishment, both of which are promoted by the accumulation of auxin
but not of sugars, whereas high levels of sugars and probably also of cytokinins act as inhibitors. Subsequent root differentiation
and growth depend on current photosynthesis. 相似文献
142.
Prabhakar Cherkupally Gerardo A. Acosta Suhas Ramesh Beatriz G. De la Torre Thavendran Govender Hendrik G. Kruger Fernando Albericio 《Amino acids》2014,46(8):1827-1838
Here we review the strategies for the solid-phase synthesis of peptides starting from the side chain of the C-terminal amino acid. Furthermore, we provide experimental data to support that C-terminal and side-chain syntheses give similar results in terms of purity. However, the stability of the two bonds that anchor the peptide to the polymer may determine the overall yield and this should be considered for the large-scale production of peptides. In addition, resins/linkers which do not subject to side reactions can be preferred for some peptides. 相似文献
143.
D Taruscio C Morciano P Laricchiuta P Mincarone F Palazzo CG Leo S Sabina R Guarino J Auld T Sejersen D Gavhed K Ritchie M Hilton-Boon J Manson PG Kanavos D Tordrup V Tzouma Y Le Cam J Senecat G Filippini S Minozzi C Del Giovane H Schünemann JJ Meerpohl B Prediger L Schell R Stefanov G Iskrov T Miteva-Katrandzhieva P Serrano-Aguilar L Perestelo-Perez MM Trujillo-Martín J Pérez-Ramos A Rivero-Santana A Brand H van Kranen K Bushby A Atalaia J Ramet L Siderius M Posada I Abaitua-Borda V Alonso Ferreira M Hens-Pérez FJ Manzanares 《Orphanet journal of rare diseases》2014,9(Z1):O14
144.
Katherine A. Mattos Viviane C. G. Oliveira Marcia Berrêdo‐Pinho Julio J. Amaral Luis Caetano M. Antunes Rossana C. N. Melo Chyntia C. D. Acosta Danielle F. Moura Roberta Olmo Jun Han Patricia S. Rosa Patrícia E. Almeida B. Brett Finlay Christoph H. Borchers Euzenir N. Sarno Patricia T. Bozza Georgia C. Atella Maria Cristina V. Pessolani 《Cellular microbiology》2014,16(6):797-815
145.
Determining the quality and complexity of next-generation sequencing data without a reference genome
Seyed Yahya Anvar Lusine Khachatryan Martijn Vermaat Michiel van Galen Irina Pulyakhina Yavuz Ariyurek Ken Kraaijeveld Johan T den Dunnen Peter de Knijff Peter AC ’t Hoen Jeroen FJ Laros 《Genome biology》2014,15(12)
We describe an open-source kPAL package that facilitates an alignment-free assessment of the quality and comparability of sequencing datasets by analyzing k-mer frequencies. We show that kPAL can detect technical artefacts such as high duplication rates, library chimeras, contamination and differences in library preparation protocols. kPAL also successfully captures the complexity and diversity of microbiomes and provides a powerful means to study changes in microbial communities. Together, these features make kPAL an attractive and broadly applicable tool to determine the quality and comparability of sequence libraries even in the absence of a reference sequence. kPAL is freely available at https://github.com/LUMC/kPAL.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0555-3) contains supplementary material, which is available to authorized users. 相似文献146.
Peggy CR Godschalk Mathijs P Bergman Raymond FJ Gorkink Guus Simons Nicole van den Braak Albert J Lastovica Hubert P Endtz Henri A Verbrugh Alex van Belkum 《BMC microbiology》2006,6(1):32-13
Background
Campylobacter jejuni is the predominant cause of antecedent infection in post-infectious neuropathies such as the Guillain-Barré (GBS) and Miller Fisher syndromes (MFS). GBS and MFS are probably induced by molecular mimicry between human gangliosides and bacterial lipo-oligosaccharides (LOS). This study describes a new C. jejuni-specific high-throughput AFLP (htAFLP) approach for detection and identification of DNA polymorphism, in general, and of putative GBS/MFS-markers, in particular. 相似文献147.
Martha N. Calderón Fanny Guzmán Orlando Acosta Carlos A. Guerrero 《International journal of peptide research and therapeutics》2012,18(4):373-382
Rotavirus infection of MA104 cells has been shown to be inhibited by cell membrane-impermeant thiol/disulfide exchange inhibitors and anti-PDI antibodies. To characterise the amino acid sequences of rotavirus structural proteins potentially mediating cell surface PDI?Csubstrate interactions, rotavirus-derived peptides from VP4 and VP7 (RRV) and VP7 (Wa), and their modified versions containing serine instead of cysteine were synthesized. Cysteine-containing VP7 peptides corresponding to residues 189?C210 or 243?C263 caused an infectivity inhibitory effect of about 64 and 85?%, respectively, when added to cells. Changing cysteine to serine significantly decreased the inhibitory effect. A cysteine-containing peptide corresponding to VP4 residues 200?C219 and its scrambled version reduced infectivity by 92 and 80?%, respectively. A cysteine to serine change in the original VP4 200?C219 peptide did not affect its inhibitory effect. Non-rotavirus related sequences containing cysteine residues efficiently inhibited rotavirus infectivity. Antibodies against VP7 residues 189?C210 or 243?C263 significantly inhibited rotavirus infectivity only after virus attachment to cells had occurred, whereas those against VP4 200?C219 peptide inhibited infectivity irrespective of whether virus or cell-attached virus was antibody-treated. A direct PDI?Cpeptide interaction was shown by ELISA for cysteine-containing VP7 and VP4 peptides. Virus?Ccell attachment was unaffected by the peptides inhibiting virus infectivity. The results showed that even though cysteine residues in the peptides tested are important in both virus infectivity inhibition and in vitro PDI?Cpeptide interaction, the accompanying amino acid sequence also plays some role. As a whole, our findings further support our hypothesis that cell surface PDI from MA104 cells might be contributing to rotavirus entry at a post-attachment step. 相似文献
148.
In vitro and in vivo characterization of an interleukin‐15 antagonist peptide by metabolic stability, 99mTc‐labeling,and biological activity assays
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Yunier Rodríguez‐Álvarez Ania Cabrales‐Rico Alejandro Perera‐Pintado Anais Prats‐Capote Hilda E. Garay‐Pérez Osvaldo Reyes‐Acosta Erik Pérez‐García Araceli Chico‐Capote Alicia Santos‐Savio 《Journal of peptide science》2018,24(4-5)
Interleukin (IL)–15 is an inflammatory cytokine that constitutes a validated therapeutic target in some immunopathologies, including rheumatoid arthritis (RA). Previously, we identified an IL‐15 antagonist peptide named [K6T]P8, with potential therapeutic application in RA. In the current work, the metabolic stability of this peptide in synovial fluids from RA patients was studied. Moreover, [K6T]P8 peptide was labeled with 99mTc to investigate its stability in human plasma and its biodistribution pattern in healthy rats. The biological activity of [K6T]P8 peptide and its dimer was evaluated in CTLL‐2 cells, using 3 different additives to improve the solubility of these peptides. The half‐life of [K6T]P8 in human synovial fluid was 5.88 ± 1.73 minutes, and the major chemical modifications included peptide dimerization, cysteinylation, and methionine oxidation. Radiolabeling of [K6T]P8 with 99mTc showed a yield of approximately 99.8%. The 99mTc‐labeled peptide was stable in a 30‐fold molar excess of cysteine and in human plasma, displaying a low affinity to plasma proteins. Preliminary biodistribution studies in healthy Wistar rats suggested a slow elimination of the peptide through the renal and hepatic pathways. Although citric acid, sucrose, and Tween 80 enhanced the solubility of [K6T]P8 peptide and its dimer, only the sucrose did not interfere with the in vitro proliferation assay used to assess their biological activity. The results here presented, reinforce nonclinical characterization of the [K6T]P8 peptide, a potential agent for the treatment of RA and other diseases associated with IL‐15 overexpression. 相似文献
149.
Joan Villanova Antonio Cano Alfonso Albacete Alfonso López Emilio Á. Cano Manuel Acosta José Manuel Pérez-Pérez 《Plant Growth Regulation》2017,81(3):511-521
Efficient propagation of uniform starting material is a critical requirement for mass production of most ornamental plants, including carnation. For some elite cultivars, the production of young plantlets is limited by poor adventitious root formation from stem cuttings. We previously characterized the molecular signature during adventitious rooting in two carnation cultivars, 2101-02 MFR and 2003 R 8, which were selected because of their contrasting rooting performance. To determine additional factors that contribute to the differences observed in adventitious rooting during the commercial scaling-up of this species, we characterized rooting performance and endogenous hormone levels in stem cuttings of these two cultivars during one production season. We found that stem cutting production declined during the harvest season in a cultivar-dependent manner. In addition, the initiation of adventitious roots in the stem cutting base depended on its endogenous auxin and cytokinin levels at harvest time, while their subsequent growth and development was mainly influenced by the physiological status of the mother plant at harvest time and of the stem cutting during the rooting process. 相似文献
150.
The variations in length and fresh and dry mass of etiolated hypocotyls of lupin during the growth have been studied. The
growth exhibited by the different zones delimited along the hypocotyl was dependent on the localization of the zone as well
as on the age of seedlings, but in both cases the pattern of growth was similar. During the period of growth studied (seedlings
7 to 21 d old), the growth of hypocotyl was basically due to cell elongation, since the relative elongation of cells was positively
correlated with the relative elongation of the hypocotyl. 相似文献