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Many plant species can be induced to flower by responding to stress factors. The short-day plants Pharbitis nil and Perilla frutescens var. crispa flower under long days in response to the stress of poor nutrition or low-intensity light. Grafting experiments using two varieties of P. nil revealed that a transmissible flowering stimulus is involved in stress-induced flowering. The P. nil and P. frutescens plants that were induced to flower by stress reached anthesis, fruited and produced seeds. These seeds germinated, and the progeny of the stressed plants developed normally. Phenylalanine ammonialyase inhibitors inhibited this stress-induced flowering, and the inhibition was overcome by salicylic acid (SA), suggesting that there is an involvement of SA in stress-induced flowering. PnFT2, a P. nil ortholog of the flowering gene FLOWERING LOCUS T (FT) of Arabidopsis thaliana, was expressed when the P. nil plants were induced to flower under poor-nutrition stress conditions, but expression of PnFT1, another ortholog of FT, was not induced, suggesting that PnFT2 is involved in stress-induced flowering.Key words: flowering, stress, phenylalanine ammonia-lyase, salicylic acid, FLOWERING LOCUS T, Pharbitis nil, Perilla frutescensFlowering in many plant species is regulated by environmental factors, such as night-length in photoperiodic flowering and temperature in vernalization. On the other hand, a short-day (SD) plant such as Pharbitis nil (synonym Ipomoea nil) can be induced to flower under long days (LD) when grown under poor-nutrition, low-temperature or high-intensity light conditions.1–9 The flowering induced by these conditions is accompanied by an increase in phenylalanine ammonia-lyase (PAL) activity.10 Taken together, these facts suggest that the flowering induced by these conditions might be regulated by a common mechanism. Poor nutrition, low temperature and high-intensity light can be regarded as stress factors, and PAL activity increases under these stress conditions.11 Accordingly, we assumed that such LD flowering in P. nil might be induced by stress. Non-photoperiodic flowering has also been sporadically reported in several plant species other than P. nil, and a review of these studies suggested that most of the factors responsible for flowering could be regarded as stress. Some examples of these factors are summarized in 12–14
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Table 1
Some cases of stress-induced floweringStress factor | Species | Flowering response | Reference |
high-intensity light | Pharbitis nil | induction | 5 |
low-intensity light | Lemna paucicostata | induction | 29 |
Perilla frutescens var. crispa | induction | 14 | |
ultraviolet C | Arabidopsis thaliana | induction | 23 |
drought | Douglas-fir | induction | 30 |
tropical pasture Legumes | induction | 31 | |
lemon | induction | 32–35 | |
Ipomoea batatas | promotion | 36 | |
poor nutrition | Pharbitis nil | induction | 3, 4, 13 |
Macroptilium atropurpureum | promotion | 37 | |
Cyclamen persicum | promotion | 38 | |
Ipomoea batatas | promotion | 36 | |
Arabidopsis thaliana | induction | 39 | |
poor nitrogen | Lemna paucicostata | induction | 40 |
poor oxygen | Pharbitis nil | induction | 41 |
low temperature | Pharbitis nil | induction | 9, 12 |
high conc. GA4/7 | Douglas-fir | promotion | 42 |
girdling | Douglas-fir | induction | 43 |
root pruning | Citrus sp. | induction | 44 |
Pharbitis nil | induction | 45 | |
mechanical stimulation | Ananas comosus | induction | 46 |
suppression of root elongation | Pharbitis nil | induction | 7 |
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Crystal H Johnson Brianna L Skinner Sharon M Dietz David Blaney Robyn M Engel George W Lathrop Alex R Hoffmaster Jay E Gee Mindy G Elrod Nathaniel Powell Henry Walke 《Comparative medicine》2013,63(6):528-535
Identification of the select agent Burkholderia pseudomallei in macaques imported into the United States is rare. A purpose-bred, 4.5-y-old pigtail macaque (Macaca nemestrina) imported from Southeast Asia was received from a commercial vendor at our facility in March 2012. After the initial acclimation period of 5 to 7 d, physical examination of the macaque revealed a subcutaneous abscess that surrounded the right stifle joint. The wound was treated and resolved over 3 mo. In August 2012, 2 mo after the stifle joint wound resolved, the macaque exhibited neurologic clinical signs. Postmortem microbiologic analysis revealed that the macaque was infected with B. pseudomallei. This case report describes the clinical evaluation of a B. pseudomallei-infected macaque, management and care of the potentially exposed colony of animals, and protocols established for the animal care staff that worked with the infected macaque and potentially exposed colony. This article also provides relevant information on addressing matters related to regulatory issues and risk management of potentially exposed animals and animal care staff.Abbreviations: CDC, Centers for Disease Control and Prevention; IHA, indirect hemagglutination assay; PEP, postexposure prophylacticBurkholderia pseudomallei, formerly known as Pseudomonas pseudomallei, is a gram-negative, aerobic, bipolar, motile, rod-shaped bacterium. B. pseudomallei infections (melioidosis) can be severe and even fatal in both humans and animals. This environmental saprophyte is endemic to Southeast Asia and northern Australia, but it has also been found in other tropical and subtropical areas of the world.7,22,32,42 The bacterium is usually found in soil and water in endemic areas and is transmitted to humans and animals primarily through percutaneous inoculation, ingestion, or inhalation of a contaminated source.8, 22,28,32,42 Human-to-human, animal-to-animal, and animal-to-human spread are rare.8,32 In December 2012, the National Select Agent Registry designated B. pseudomallei as a Tier 1 overlap select agent.39 Organisms classified as Tier 1 agents present the highest risk of deliberate misuse, with the most significant potential for mass casualties or devastating effects to the economy, critical infrastructure, or public confidence. Select agents with this status have the potential to pose a severe threat to human and animal health or safety or the ability to be used as a biologic weapon.39Melioidosis in humans can be challenging to diagnose and treat because the organism can remain latent for years and is resistant to many antibiotics.12,37,41
B. pseudomallei can survive in phagocytic cells, a phenomenon that may be associated with latent infections.19,38 The incubation period in naturally infected animals ranges from 1 d to many years, but symptoms typically appear 2 to 4 wk after exposure.13,17,35,38 Disease generally presents in 1 of 2 forms: localized infection or septicemia.22 Multiple methods are used to diagnose melioidosis, including immunofluorescence, serology, and PCR analysis, but isolation of the bacteria from blood, urine, sputum, throat swabs, abscesses, skin, or tissue lesions remains the ‘gold standard.’9,22,40,42 The prognosis varies based on presentation, time to diagnosis, initiation of appropriate antimicrobial treatment, and underlying comorbidities.7,28,42 Currently, there is no licensed vaccine to prevent melioidosis.There are several published reports of naturally occurring melioidosis in a variety of nonhuman primates (NHP; 2,10,13,17,25,30,31,35 The first reported case of melioidosis in monkeys was recorded in 1932, and the first published case in a macaque species was in 1966.30 In the United States, there have only been 7 documented cases of NHP with B. pseudomallei infection.2,13,17 All of these cases occurred prior to the classification of B. pseudomallei as a select agent. Clinical signs in NHP range from subclinical or subacute illness to acute septicemia, localized infection, and chronic infection. NHP with melioidosis can be asymptomatic or exhibit clinical signs such as anorexia, wasting, purulent drainage, subcutaneous abscesses, and other soft tissue lesions. Lymphadenitis, lameness, osteomyelitis, paralysis and other CNS signs have also been reported.2,7,10,22,28,32 In comparison, human''s clinical signs range from abscesses, skin ulceration, fever, headache, joint pain, and muscle tenderness to abdominal pain, anorexia, respiratory distress, seizures, and septicemia.7,9,21,22
Open in a separate windowaCountry reflects the location where the animal was housed at the time of diagosis.Here we describe a case of melioidosis diagnosed in a pigtail macaque (Macaca nemestrina) imported into the United States from Indonesia and the implications of the detection of a select agent identified in a laboratory research colony. We also discuss the management and care of the exposed colony, zoonotic concerns regarding the animal care staff that worked with the shipment of macaques, effects on research studies, and the procedures involved in reporting a select agent incident. 相似文献
Table 1.
Summary of reported cases of naturally occurring Burkholderia pseudomalleiinfections in nonhuman primatesCountrya | Imported from | Date reported | Species | Reference |
Australia | Borneo | 1963 | Pongo sp. | 36 |
Brunei | Unknown | 1982 | Orangutan (Pongo pygmaeus) | 33 |
France | 1976 | Hamlyn monkey (Cercopithecus hamlyni) Patas monkey (Erythrocebus patas) | 11 | |
Great Britain | Philippines and Indonesia | 1992 | Cynomolgus monkey (Macaca fascicularis) | 10 |
38 | ||||
Malaysia | Unknown | 1966 | Macaca spp. | 30 |
Unknown | 1968 | Spider monkey (Brachytelis arachnoides) Lar gibbon (Hylobates lar) | 20 | |
Unknown | 1969 | Pig-tailed macaque (Macaca nemestrina) | 35 | |
Unknown | 1984 | Banded leaf monkey (Presbytis melalophos) | 25 | |
Singapore | Unknown | 1995 | Gorillas, gibbon, mandrill, chimpanzee | 43 |
Thailand | Unknown | 2012 | Monkey | 19 |
United States | Thailand | 1970 | Stump-tailed macaque (Macaca arctoides) | 17 |
India | Pig-tailed macaque (Macaca nemestrina) | |||
Africa | Rhesus macaque (Macaca mulatta) Chimpanzee (Pan troglodytes) | |||
Unknown | 1971 | Chimpanzee (Pan troglodytes) | 3 | |
Malaysia | 1981 | Pig-tailed macaque (Macaca nemestrina) | 2 | |
Wild-caught, unknown | 1986 | Rhesus macaque (Macaca mulatta) | 13 | |
Indonesia | 2013 | Pig-tailed macaque (Macaca nemestrina) | Current article |
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Nicholas Holton Kate Harrison Takao Yokota Gerard J Bishop 《Plant signaling & behavior》2008,3(1):54-55
Brassinosteroids (BRs) are perceived by Brassinosteroid Insensitive 1 (BRI1), that encodes a leucine-rich repeat receptor kinase. Tomato BRI1 has previously been implicated in both systemin and BR signalling. The role of tomato BRI1 in BR signalling was confirmed, however it was found not to be essential for systemin/wound signalling. Tomato roots were shown to respond to systemin but this response varied according to the species and growth conditions. Overall the data indicates that mutants defective in tomato BRI1 are not defective in systemin-induced wound signalling and that systemin perception can occur via a non-BRI1 mechanism.Key words: tomato BRI1, brassinosteroids, systemin, wound signallingBrassinosteroids (BRs) are steroid hormones that are essential for normal plant growth. The most important BR receptor in Arabidopsis is BRASSINOSTERIOD INSENSITIVE 1 (BRI1), a serine/threonine kinase with a predicted extracellular domain of ∼24 leucine-rich repeats (LRRs).1,2 BRs bind to BRI1 via a steroid-binding domain that includes LRR 21 and a so-called “island” domain.2,3 In tomato a BRI1 orthologue has been identified that when mutated, as in the curl3 (cu3) mutation, results in BR-insensitive dwarf plants.4 Tomato BRI1 has also been purified as a systemin-binding protein.5 Systemin is an eighteen amino acid peptide, which is produced by post-translational cleavage of prosystemin. Systemin has been implicated in wound signalling and is able to induce the production of jasmonate, protease inhibitors (PIN) and rapid alkalinization of cell suspensions (reviewed in ref. 6).To clarify whether tomato BRI1 was indeed a dual receptor it was important to first confirm its role in BR signalling. Initially this was carried out by genetic complementation of the cu3 mutant phenotype.7 Overexpression of tomato BRI1 restored the dwarf phenotype and BR sensitivity and normalized BR levels (35S:TomatoBRI1 complemented line Wt* cu3* 6-deoxocathasterone 566 964 676 6-deoxoteasterone nd 47 48 3-dehydro-6-deoxoteasterone 87 62 69 6-deoxotyphasterol nd 588 422 6-deoxocastasterone 1,755 6,247 26,210 castasterone 255 637 17,428 brassinolide nd nd nd