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71.
François Barrieu Dominique Thomas Danièle Marty-Mazars Maryse Charbonnier Francis Marty 《Planta》1998,204(3):335-344
The vacuolar membrane (tonoplast) of plant cells contains aquaporins, protein channels that facilitate the selective transport
of water. These tonoplast intrinsic proteins (TIPs) of 23–29 kDa belong to the ancient major intrinsic protein (MIP) family.
A monospecific polyclonal antiserum directed against a 26 kDa intrinsic protein from the tonoplast of meristematic cells from
cauliflower (Brassica oleracea L. var. botrytis) was used to screen a cDNA library. Two distinct cDNAs have been isolated. Both clones, c26-1 and c26-2, encode closely related TIPs. The c26-1 insert, consisting of 933 bp upstream of the poly(A) tail, is a full-length cDNA with an open reading frame encoding a protein
of 251 amino acids with a calculated Mr of 25 500. The c26-2 insert is a 5′ truncated cDNA. The two cDNAs share 90.5% sequence identity within their overlapping coding regions but only
35% sequence identity in the 3′␣untranslated regions, indicating that highly related TIP-encoding genes are expressed in meristematic
cells. Although TIPs have previously been found in a variety of cell types, they have not been found in meristems. The derived
amino acid sequences (BobTIP26-1 and BobTIP26-2, respectively) closely resemble the aquaporin γ-TIP from Arabidopsis thaliana. Northern blot analysis and in situ hybridization show that BobTIP26 mRNAs preferentially accumulate in highly meristematic cells, mostly before and during cell enlargement, and in the living
cells of the xylem. This differential pattern of expression is also found by immunodetection of BobTIP26 polypeptides. The
gene expression patterns are discussed with respect to the probable function of the gene products.
Received: 27 March 1997 / Accepted: 20 May 1997 相似文献
72.
A Genetic Analysis of Interactions with Spc110p Reveals Distinct Functions of Spc97p and Spc98p, Components of the Yeast γ-Tubulin Complex 下载免费PDF全文
Thu Nguyen Dani B.N. Vinh Douglas K. Crawford Trisha N. Davis 《Molecular biology of the cell》1998,9(8):2201-2216
The spindle pole body (SPB) in Saccharomyces cerevisiae functions as the microtubule-organizing center. Spc110p is an essential structural component of the SPB and spans between the central and inner plaques of this multilamellar organelle. The amino terminus of Spc110p faces the inner plaque, the substructure from which spindle microtubules radiate. We have undertaken a synthetic lethal screen to identify mutations that enhance the phenotype of the temperature-sensitive spc110–221 allele, which encodes mutations in the amino terminus. The screen identified mutations in SPC97 and SPC98, two genes encoding components of the Tub4p complex in yeast. The spc98–63 allele is synthetic lethal only with spc110 alleles that encode mutations in the N terminus of Spc110p. In contrast, the spc97 alleles are synthetic lethal with spc110 alleles that encode mutations in either the N terminus or the C terminus. Using the two-hybrid assay, we show that the interactions of Spc110p with Spc97p and Spc98p are not equivalent. The N terminus of Spc110p displays a robust interaction with Spc98p in two different two-hybrid assays, while the interaction between Spc97p and Spc110p is not detectable in one strain and gives a weak signal in the other. Extra copies of SPC98 enhance the interaction between Spc97p and Spc110p, while extra copies of SPC97 interfere with the interaction between Spc98p and Spc110p. By testing the interactions between mutant proteins, we show that the lethal phenotype in spc98–63 spc110–221 cells is caused by the failure of Spc98–63p to interact with Spc110–221p. In contrast, the lethal phenotype in spc97–62 spc110–221 cells can be attributed to a decreased interaction between Spc97–62p and Spc98p. Together, these studies provide evidence that Spc110p directly links the Tub4p complex to the SPB. Moreover, an interaction between Spc98p and the amino-terminal region of Spc110p is a critical component of the linkage, whereas the interaction between Spc97p and Spc110p is dependent on Spc98p. 相似文献
73.
The time of appearance and tissue concentrations of substance P-like immunoreactivity (SP-LI) were studied in 53 human fetuses aged 8-21 weeks. Detectable amounts were present at 8 weeks of gestation in available fragments of spinal cord and intestine. Thereafter, the tissue concentrations were highest in spinal cord, intermediate in hypothalamus and lowest in digestive tract. Except for a significant increase in the intestinal wall, the concentrations did not vary from the 8-14 to the 15-21 week period. At chromatography, SP-LI in extracts of spinal cord and intestine was essentially eluted in the volume of the synthetic undecapeptide. Using the indirect immunofluorescence technique, the localization of SP-LI positive structures in the digestive tract was studied in 5 fetuses aged 12-18 weeks. Scarce cell bodies were observed in the myenteric plexus. Nerve fibers were recognized in the muscular layer, in the myenteric plexus and in connective tissue of pancreas. The present results demonstrate the early appearance of SP-LI positive structures both in central nervous system and in the enteric nervous system in the human fetus. In the age range tested, SP-LI concentrations were noticeably higher in spinal cord and hypothalamus than in the digestive tract. 相似文献
74.
75.
Juan Bécares Manuel García-Tarrasón Dani Villero Santiago Bateman Lluís Jover Víctor García-Matarranz Carolina Sanpera José Manuel Arcos 《PloS one》2015,10(4)
Although the breeding ecology of Audouin’s gull has been widely studied, its spatial distribution patterns have received little attention. We assessed the foraging movements of 36 GPS-tracked adult Audouin’s gulls breeding at the Ebro Delta (NW Mediterranean), coinciding with the incubation period (May 2011). This also coincided with a trawling moratorium northwards from the colony. We modelled the distribution of the gulls by combining these tracking data with environmental variables (including fishing activities from Vessel Monitoring System, VMS), using Maxent. The modelling range included both marine and terrestrial areas. Models were produced separately for every 2h time interval across the day, and for 2 fishing activity scenarios (workdays vs. weekends), allowing to assess the spatio-temporal distribution patterns of the gulls and the degree of association with fisheries. During workdays, gull distribution at sea fully matched with fishing activities, both trawling (daylight) and purse-seining (nightime). Gulls tended to avoid the area under trawling moratorium, confirming the high influence of fisheries on the distribution patterns of this species. On weekends, gulls made lesser use of the sea and tended to increase the use of rice fields. Overall, Audouin’s gull activity was more intense during dailight hours, although birds also showed nocturnal activity, on both workdays and weekends. Nocturnal patterns at sea were more disperse during the latter, probably because these gulls are able to capture small pelagic fish at night in natural conditions, but tend to congregate around purse-seiners (which would enhance their foraging efficiency) in workdays. These results provide important insight for the management of this species. This is of particular relevance under the current scenario of European fisheries policies, since new regulations are aimed at eliminating discards, and this would likely influence Audouin’s gull populations. 相似文献
76.
Two main mechanisms are thought to affect the prevalence of endophyte-grass symbiosis in host populations: the mode of endophyte transmission, and the fitness differential between symbiotic and non-symbiotic plants. These mechanisms have mostly been studied in synthetic grass populations. If we are to improve our understanding of the ecological and evolutionary dynamics of such symbioses, we now need to determine the combinations of mechanisms actually operating in the wild, in populations shaped by evolutionary history. We used a demographic population modeling approach to identify the mechanisms operating in a natural stand of an intermediate population (i.e. 50% of plants symbiotic) of the native grass Festuca eskia. We recorded demographic data in the wild over a period of three years, with manipulation of the soil resources for half the population. We developed two stage-structured matrix population models. The first model concerned either symbiotic or non-symbiotic plants. The second model included both symbiotic and non-symbiotic plants and took endophyte transmission rates into account. According to our models, symbiotic had a significantly higher population growth rate than non-symbiotic plants, and endophyte prevalence was about 58%. Endophyte transmission rates were about 0.67 or 0.87, depending on the growth stage considered. In the presence of nutrient supplementation, population growth rates were still significantly higher for symbiotic than for non-symbiotic plants, but endophyte prevalence fell to 0%. At vertical transmission rates below 0.10–0.20, no symbiosis was observed. Our models showed that a positive benefit of the endophyte and vertical transmission rates of about 0.6 could lead to the coexistence of symbiotic and non-symbiotic F. eskia plants. The positive effect of the symbiont on host is not systematically associated with high transmission rates of the symbiont over short time scales, in particular following an environmental change. 相似文献
77.
Shai Efrati Haim Golan Yair Bechor Yifat Faran Shir Daphna-Tekoah Gal Sekler Gregori Fishlev Jacob N. Ablin Jacob Bergan Olga Volkov Mony Friedman Eshel Ben-Jacob Dan Buskila 《PloS one》2015,10(5)
BackgroundFibromyalgia Syndrome (FMS) is a persistent and debilitating disorder estimated to impair the quality of life of 2–4% of the population, with 9:1 female-to-male incidence ratio. FMS is an important representative example of central nervous system sensitization and is associated with abnormal brain activity. Key symptoms include chronic widespread pain, allodynia and diffuse tenderness, along with fatigue and sleep disturbance. The syndrome is still elusive and refractory. The goal of this study was to evaluate the effect of hyperbaric oxygen therapy (HBOT) on symptoms and brain activity in FMS.ConclusionsThe study provides evidence that HBOT can improve the symptoms and life quality of FMS patients. Moreover, it shows that HBOT can induce neuroplasticity and significantly rectify abnormal brain activity in pain related areas of FMS patients.
Trial Registration
ClinicalTrials.gov NCT01827683相似文献78.
79.
Martyn Lewis Linda S. Chesterton Julius Sim Christian D. Mallen Elaine M. Hay Dani?lle A. van der Windt 《PloS one》2015,10(8)
Background
The TATE trial was a multicentre pragmatic randomized controlled trial of supplementing primary care management (PCM)–consisting of a GP consultation followed by information and advice on exercises–with transcutaneous electrical nerve stimulation (TENS), to reduce pain intensity in patients with tennis elbow. This paper reports the health economic evaluation.Methods and Findings
Adults with new diagnosis of tennis elbow were recruited from 38 general practices in the UK, and randomly allocated to PCM (n = 120) or PCM plus TENS (n = 121). Outcomes included reduction in pain intensity and quality-adjusted-life-years (QALYs) based on the EQ5D and SF6D. Two economic perspectives were evaluated: (i) healthcare–inclusive of NHS and private health costs for the tennis elbow; (ii) societal–healthcare costs plus productivity losses through work absenteeism. Mean outcome and cost differences between the groups were evaluated using a multiple imputed dataset as the base case evaluation, with uncertainty represented in cost-effectiveness planes and through probabilistic cost-effectiveness acceptability curves). Incremental healthcare cost was £33 (95%CI -40, 106) and societal cost £65 (95%CI -307, 176) for PCM plus TENS. Mean differences in outcome were: 0.11 (95%CI -0.13, 0.35) for change in pain (0–10 pain scale); -0.015 (95%CI -0.058, 0.029) for QALYEQ5D; 0.007 (95%CI -0.022, 0.035) for QALYSF6D (higher score differences denote greater benefit for PCM plus TENS). The ICER (incremental cost effectiveness ratio) for the main evaluation of mean difference in societal cost (£) relative to mean difference in pain outcome was -582 (95%CI -8666, 8113). However, incremental ICERs show differences in cost–effectiveness of additional TENS, according to the outcome being evaluated.Conclusion
Our findings do not provide evidence for or against the cost-effectiveness of TENS as an adjunct to primary care management of tennis elbow. 相似文献80.
Jean-Louis Spadoni Pierre Rucart Sigrid Le Clerc Dani?lle van Manen Cédric Coulonges Damien Ulveling Vincent Laville Taoufik Labib Lieng Taing Olivier Delaneau Matthieu Montes Hanneke Schuitemaker Josselin Noirel Jean-Fran?ois Zagury 《PloS one》2015,10(9)