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1.
Adventitious shoots were formed through callus on leaf explants of Eucalyptus camaldulensis Dehnh. (River red gum) taken from shoot cultures of mature trees. Callus formed in dark on a medium containing 1 g/l casein hydrolysate, 3 mg/l 1-naphthaleneacetic acid, 0.1 mg/l 6-benzyladenine and 50 g/l sucrose. Shoot initiation occurred in 4 weeks on calli shifted to light on a regeneration medium containing 10% coconut milk, 0.5 mg/l 6-benzyladenine and 20 g/l sucrose. Rooting occured in dark on a liquid medium containing 4 mg/l 1-naphthaleneacetic acid. Zygotic embryos of Eucalyptus citriodora Hook f. (Lemon scented gum) cultured in dark on a medium containing 3 mg/l 1-naphthaleneacetic acid and 50 g/l sucrose formed somatic embryoids which grew to normal plantlets on the same regeneration medium used for organogenesis.Abbreviations BAP
6-benzyladenine
- CH
Casein hydrolysate
- CM
Coconut Milk
- NAA
1-naphthaleneacetic acid
NCL Communication no. 4162 相似文献
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Malaria, caused by infection with Plasmodium parasites, remains a significant global health concern. For decades, genetic intractability and limited tools hindered our ability to study essential proteins and pathways in Plasmodium falciparum, the parasite associated with the most severe malaria cases. However, recent years have seen major leaps forward in the ability to genetically manipulate P. falciparum parasites and conditionally control protein expression/function. The conditional knockdown systems used in P. falciparum target all 3 components of the central dogma, allowing researchers to conditionally control gene expression, translation, and protein function. Here, we review some of the common knockdown systems that have been adapted or developed for use in P. falciparum. Much of the work done using conditional knockdown approaches has been performed in asexual, blood-stage parasites, but we also highlight their uses in other parts of the life cycle and discuss new ways of applying these systems outside of the intraerythrocytic stages. With the use of these tools, the field’s understanding of parasite biology is ever increasing, and promising new pathways for antimalarial drug development are being discovered. 相似文献
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The anabolic action of intermittent parathyroid hormone on cortical bone depends partly on its ability to induce nitric oxide‐mediated vasorelaxation in BALB/c mice 下载免费PDF全文
S Gohin A Carriero C Chenu AA Pitsillides TR Arnett M Marenzana 《Cell biochemistry and function》2016,34(2):52-62
There is strong evidence that vasodilatory nitric oxide (NO) donors have anabolic effects on bone in humans. Parathyroid hormone (PTH), the only osteoanabolic drug currently approved, is also a vasodilator. We investigated whether the NO synthase inhibitor L‐NAME might alter the effect of PTH on bone by blocking its vasodilatory effect. BALB/c mice received 28 daily injections of PTH[1–34] (80 µg/kg/day) or L‐NAME (30 mg/kg/day), alone or in combination. Hindlimb blood perfusion was measured by laser Doppler imaging. Bone architecture, turnover and mechanical properties in the femur were analysed respectively by micro‐CT, histomorphometry and three‐point bending. PTH increased hindlimb blood flow by >30% within 10 min of injection (P < 0.001). Co‐treatment with L‐NAME blocked the action of PTH on blood flow, whereas L‐NAME alone had no effect. PTH treatment increased femoral cortical bone volume and formation rate by 20% and 110%, respectively (P < 0.001). PTH had no effect on trabecular bone volume in the femoral metaphysis although trabecular thickness and number were increased and decreased by 25%, respectively. Co‐treatment with L‐NAME restricted the PTH‐stimulated increase in cortical bone formation but had no clear‐cut effects in trabecular bone. Co‐treatment with L‐NAME did not affect the mechanical strength in femurs induced by iPTH. These results suggest that NO‐mediated vasorelaxation plays partly a role in the anabolic action of PTH on cortical bone. © 2016 The Authors. Cell Biochemistry and Function published by John Wiley & Sons, Ltd. 相似文献
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Thermoluminescence and photoluminescence studies on γ‐ray‐irradiated Ce3+,Tb3+‐doped potassium chloride single crystals 下载免费PDF全文
Single crystals of KCl doped with Ce3+,Tb3+ were grown using the Bridgeman–Stockbarger technique. Thermoluminescence (TL), optical absorption, photoluminescence (PL), photo‐stimulated luminescence (PSL), and thermal‐stimulated luminescence (TSL) properties were studied after γ‐ray irradiation at room temperature. The glow curve of the γ‐ray‐irradiated crystal exhibits three peaks at 420, 470 and 525 K. F‐Light bleaching (560 nm) leads to a drastic change in the TL glow curve. The optical absorption measurements indicate that F‐ and V‐centres are formed in the crystal during γ‐ray irradiation. It was attempted to incorporate a broad band of cerium activator into the narrow band of terbium in the KCl host without a reduction in the emission intensity. Cerium co‐doped KCl:Tb crystals showed broad band emission due to the d–f transition of cerium and a reduction in the intensity of the emission peak due to 5D3–7Fj (j = 3, 4) transition of terbium, when excited at 330 nm. These results support that energy transfer occurs from cerium to terbium in the KCl host. Co‐doping Ce3+ ions greatly intensified the excitation peak at 339 nm for the emission at 400 nm of Tb3+. The emission due to Tb3+ ions was confirmed by PSL and TSL spectra. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Radhika V Proikas-Cezanne T Jayaraman M Onesime D Ha JH Dhanasekaran DN 《Nature chemical biology》2007,3(6):325-330
With the increasing threat of environmental toxicants including biological and chemical warfare agents, fabricating innovative biomimetic systems to detect these harmful agents is critically important. With the broad objective of developing such a biosensor, here we report the construction of a Saccharomyces cerevisiae strain containing the primary components of the mammalian olfactory signaling pathway. In this engineered yeast strain, WIF-1alpha, olfactory receptor signaling is coupled to green fluorescent protein expression. Using this 'olfactory yeast', we screened for olfactory receptors that could report the presence of the odorant 2,4-dinitrotoluene, an explosive residue mimic. With this approach, we have identified the novel rat olfactory receptor Olfr226, which is closely related to the mouse olfactory receptors Olfr2 and MOR226-1, as a 2,4-dinitrotoluene-responsive receptor. 相似文献
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We previously reported that 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] is metabolized into 1alpha,25-dihydroxy-3-epi-vitamin D(3) [1alpha,25(OH)(2)-3-epi-D(3)] in primary cultures of neonatal human keratinocytes. We now report that 1alpha,25(OH)(2)-3-epi-D(3) itself is further metabolized in human keratinocytes into several polar metabolites. One of the polar metabolite was unequivocally identified as 1alpha,23,25-trihydroxy-3-epi-vitamin D(3) by mass spectrometry and its sensitivity to sodium periodate. Three of the polar metabolites were identified as 1alpha,24,25-trihydroxy-3-epi-vitamin D(3), 1alpha,25-dihydroxy-24-oxo-3-epi-vitamin D(3) and 1alpha,23,25-trihydroxy-24-oxo-3-epi-vitamin D(3) by comigration with authentic standards on both straight and reverse phase HPLC systems. In addition to the polar metabolites, 1alpha,25(OH)(2)-3-epi-D(3) was also metabolized into two less polar metabolites. A possible structure of either 1alphaOH-3-epi-D(3)-20,25-cyclic ether or 1alphaOH-3-epi-D(3)-24,25-epoxide was assigned to one of the less polar metabolites through mass spectrometry. Thus, we indicate for the first time that 1alpha,25(OH)(2)-3-epi-D(3) is metabolized in neonatal human keratinocytes not only via the same C-24 and C-23 oxidation pathways like its parent, 1alpha,25(OH)(2)D(3); but also is metabolized into a less polar metabolite via a pathway that is unique to 1alpha,25(OH)(2)-3-epi-D(3). 相似文献
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Nuclear gene trees and the phylogenetic relationships of the mangabeys (Primates: Papionini) 总被引:3,自引:1,他引:2
Phylogenetic relationships of mangabeys within the Old World monkey tribe
Papionini are inferred from analyses of nuclear DNA sequences from five
unlinked loci. The following conclusions are strongly supported, based on
congruence among trees derived for the five separate gene regions: (1)
mangabeys are polyphyletic within the Papionini; (2) Cercocebus is the
sister taxon to the genus Mandrillus; and (3) Lophocebus belongs to a clade
with Papio and Theropithecus, with Papio as its most likely sister taxon.
Morphologically based phylogenies positing mangabey monophyly were
evaluated by mapping the sequences for each locus on these trees. The data
seem to fit these trees poorly in both maximum-parsimony and likelihood
analyses. Incongruence among nuclear gene trees occurred in the
interrelationships among Lophocebus, Papio, and Theropithecus. Several
factors that may account for this incongruence are discussed, including
sampling error, random lineage sorting, and introgression.
相似文献