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91.
Ulrike Pichler Michael Hauser Martin Wolf Maria Livia Bernardi Gabriele Gadermaier Richard Weiss Christof Ebner Hidenori Yokoi Toshiro Takai Alain Didierlaurent Chiara Rafaiani Peter Briza Adriano Mari Heidrun Behrendt Michael Wallner Fátima Ferreira 《PloS one》2015,10(5)
BackgroundPollen released by allergenic members of the botanically unrelated families of Asteraceae and Cupressaceae represent potent elicitors of respiratory allergies in regions where these plants are present. As main allergen sources the Asteraceae species ragweed and mugwort, as well as the Cupressaceae species, cypress, mountain cedar, and Japanese cedar have been identified. The major allergens of all species belong to the pectate lyase enzyme family. Thus, we thought to investigate cross-reactivity pattern as well as sensitization capacities of pectate lyase pollen allergens in cohorts from distinct geographic regions.MethodsThe clinically relevant pectate lyase pollen allergens Amb a 1, Art v 6, Cup a 1, Jun a 1, and Cry j 1 were purified from aqueous pollen extracts, and patients´ sensitization pattern of cohorts from Austria, Canada, Italy, and Japan were determined by IgE ELISA and cross-inhibition experiments. Moreover, we performed microarray experiments and established a mouse model of sensitization.ResultsIn ELISA and ELISA inhibition experiments specific sensitization pattern were discovered for each geographic region, which reflected the natural allergen exposure of the patients. We found significant cross-reactivity within Asteraceae and Cupressaceae pectate lyase pollen allergens, which was however limited between the orders. Animal experiments showed that immunization with Asteraceae allergens mainly induced antibodies reactive within the order, the same was observed for the Cupressaceae allergens. Cross-reactivity between orders was minimal. Moreover, Amb a 1, Art v 6, and Cry j 1 showed in general higher immunogenicity.ConclusionWe could cluster pectate lyase allergens in four categories, Amb a 1, Art v 6, Cup a 1/Jun a 1, and Cry j 1, respectively, at which each category has the potential to sensitize predisposed individuals. The sensitization pattern of different cohorts correlated with pollen exposure, which should be considered for future allergy diagnosis and therapy. 相似文献
92.
Yuya Kumagai Takao Ojima 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(2):138-144
Two types of β-1,3-glucanases, AkLam36 and AkLam33 with the molecular masses of 36 kDa and 33 kDa, respectively, were isolated from the digestive fluid of the common sea hare Aplysia kurodai. AkLam36 was regarded as an endolytic enzyme (EC 3.2.1.6) degrading laminarin and laminarioligosaccharides to laminaritriose, laminaribiose, and glucose, while AkLam33 was regarded as an exolytic enzyme (EC 3.2.1.58) directly producing glucose from polymer laminarin. AkLam36 showed higher activity toward β-1,3-glucans with a few β-1,6-linked glucose branches such as Laminaria digitata laminarin (LLam) than highly branched β-1,3-glucans such as Eisenia bicyclis laminarin (ELam). AkLam33 showed moderate activity toward both ELam and LLam and high activity toward smaller substrates such as laminaritetraose and laminaritriose. Although both enzymes did not degrade laminaribiose as a sole substrate, they were capable of degrading it via transglycosylation reaction with laminaritriose. The N-terminal amino-acid sequences of AkLam36 and AkLam33 indicated that both enzymes belong to the glycosyl hydrolase family 16 like other molluscan β-1,3-glucanases. 相似文献
93.
Yoshida Takanori Nagai Hisako Yahara Tetsukazu Tachida Hidenori 《Journal of plant research》2010,123(4):607-616
Zanthoxylum ailanthoides Siebold & Zucc. is one of the most frequently encountered pioneer trees in Japanese warm–temperate evergreen oak forests.
Our previous study in one region of Japan suggested high levels of population differentiation and putative natural selection
acting on one of the nuclear loci analyzed. Here, we extend our analysis to study the genetic structure of 10 populations
of Z. ailanthoides across Japan using 9 simple sequence repeat (SSR) loci for a better understanding of its genetic structure. First, the southernmost
population (Kagoshima) in the samples was found to have the highest genetic diversity, suggesting there was a glacial refugium
at or near the location of the population. Second, relatively strong genetic differentiation was found among populations,
and there was a positive correlation between genetic distances and geographic distances (Mantel test; P < 0.001). Based on this information, we analyzed nucleotide variation at the putatively selected locus homologous to the
gene encoding the ADP-glucose pyrophosphorylase large subunit (agpL). Despite the strong genetic differentiation among populations suggested by the SSR loci, the agpL locus was monomorphic in almost all populations analyzed. The results of this study strongly supported the possibility of
a selective sweep at or near the agpL locus. 相似文献
94.
Pollen-expressed F-box gene family and mechanism of S-RNase-based gametophytic self-incompatibility (GSI) in Rosaceae 总被引:1,自引:0,他引:1
Many species of Rosaceae, Solanaceae, and Plantaginaceae exhibit S-RNase-based self-incompatibility (SI) in which pistil-part
specificity is controlled by S locus-encoded ribonuclease (S-RNase). Although recent findings revealed that S locus-encoded F-box protein, SLF/SFB, determines pollen-part specificity, how these pistil- and pollen-part S locus products interact in vivo and elicit the SI reaction is largely unclear. Furthermore, genetic studies suggested that
pollen S function can differ among species. In Solanaceae and the rosaceous subfamily Maloideae (e.g., apple and pear), the coexistence
of two different pollen S alleles in a pollen breaks down SI of the pollen, a phenomenon known as competitive interaction. However, competitive interaction
seems not to occur in the subfamily Prunoideae (e.g., cherry and almond) of Rosaceae. Furthermore, the effect of the deletion
of pollen S seems to vary among taxa. This review focuses on the potential differences in pollen-part function between subfamilies of
Rosaceae, Maloideae, and Prunoideae, and discusses implications for the mechanistic divergence of the S-RNase-based SI. 相似文献
95.
The photoreceptors for chloroplast photorelocation movement have been known, but the signal(s) raised by photoreceptors remains unknown. To know the properties of the signal(s) for chloroplast accumulation movement, we examined the speed of signal transferred from light-irradiated area to chloroplasts in gametophytes of Adiantum capillus-veneris. When dark-adapted gametophyte cells were irradiated with a microbeam of various light intensities of red or blue light for 1 min or continuously, the chloroplasts started to move towards the irradiated area. The speed of signal transfer was calculated from the relationship between the timing of start moving and the distance of chloroplasts from the microbeam and was found to be constant at any light conditions. In prothallial cells, the speed was about 1.0 µm min−1 and in protonemal cells about 0.7 µm min−1 towards base and about 2.3 µm min−1 towards the apex. We confirmed the speed of signal transfer in Arabidopsis thaliana mesophyll cells under continuous irradiation of blue light, as was about 0.8 µm min−1. Possible candidates of the signal are discussed depending on the speed of signal transfer.Key words: Adiantum capillus-veneris, Arabidopsis thaliana, blue light, chloroplast movement, microbeam, red light, signalOrganelle movement is essential for plant growth and development and tightly regulated by environmental conditions.1 It is well known that light regulates chloroplast movement in various plant species. Chloroplast movement can be separated into three categories, (1) photoperception by photoreceptors, (2) signal transduction from photoreceptor to chloroplasts and (3) movement of chloroplasts and has been analyzed from a physiological point of view.2 We recently identified the photoreceptors in Arabidopsis thaliana, fern Adiantum capillus-veneris, and moss Physcomitrella patens. In A. thaliana, phototropin 2 (phot2) mediates the avoidance movement,3,4 whereas both phototropin 1 (phot1) and phot2 mediate the accumulation response.5 A chimeric photoreceptor neochrome 1 (neo1)6 was identified as a red/far-red and blue light receptor that mediates red as well as blue light-induced chloroplast movement in A. capillusveneris.7 Interestingly, neo1 mediated red and blue light-induced nuclear movement and negative phototropic response of A. capillus-veneris rhizoid cells.8,9 On the mechanism of chloroplast movement, we also found a novel structure of actin filaments that appeared between chloroplast and the plasma membrane at the front side of moving chloroplast.10 Recent studies using the technique of microbeam irradiation have revealed that chloroplasts do not have a polarity for light-induced accumulation movement and can move freely in any direction both in A. capillus-veneris prothallial cells and in A. thaliana mesophyll cells.11 However, the signal that may be released from photoreceptors and transferred to chloroplasts remains unknown.To understand the properties of the signal for the chloroplast accumulation response, we examined the speed of signal transfer in dark-adapted A. capillus-veneris gametophyte cells and A. thaliana mesophyll cells by partial cell irradiation with a red and/or blue microbeam of various light intensities for 1 min and the following continuous irradiation, respectively.12As shown in Figure 1, the relation between the distance of chloroplasts from the microbeam and the timing when each chloroplast started moving toward the microbeam irradiated area (shown as black dots in Fig. 1) was obtained and plotted. The lag time between the onset of microbeam irradiation and the timing of start moving of chloroplasts is the time period needed for a signal to reach each chloroplast. To obtain more accurate data many chloroplasts at various positions were used. The slope of the approximate line indicates the average speed of the signal transfer. Shown with a protonemal cell at the left side of this figure is an instance where the speed of signal transfer from basal-to-apical (acropetal) direction is obtained.Open in a separate windowFigure 1How to calculate the speed of signal transfer in the basal cell of two-celled protonema of Adiantum capillus-veneris. The relationship between the distance of chloroplast position from the edge of the microbeam to the center of each chloroplast as shown in left side of figure and the timing of chloroplast movement initiated shown as the black dots was obtained. Inclination of the approximate lines connecting dots indicates the speeds of the signal transfer.In protonemal cells, which are tip-growing linear cells, the average speed of signal transfer was about 2.3 µm min−1 from basal-to-apical (acropetal) and about 0.7 µm min−1 from apical-to-basal (basipetal) directions. These values were almost constant irrespective of light intensity, wavelength, irradiation period, and the region of the cell irradiated.12 The difference of speed between basipetal and acropetal directions may be depending on cell polarity. The signal transfer in prothallial cells of A. capillus-veneris and mesophyll cells of A. thaliana was about 1.0 µm min−1 to any direction, probably because they may not have a polarity comparing to protonemal cells or have a weak polarity if any. Thus, the speed of signal transfer must be conserved in most land plants,12 if not influenced by strong polarity. R1W m−2 R1W m−2 B1W m−2 R0.1W m−2 R10W m−2 B10W m−2 1 min countinuous countinuous countinuous countinuous countinuous Protonemal cell (towards apical region) 2.32 2.37 2.28 2.41 2.39 Protonemal cell (towards basal region) 0.58 0.73 0.80 0.74 0.86 Prothallial cell 1.13 0.92 1.10 1.08 0.95 Arabidopsis thaliana 0.70