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231.
In this report, we designed conjugates of an antigen peptide with the immunosuppressive vitamins all‐trans retinoic acid (ATRA) and vitamin D3 for efficient induction of antigen‐specific immunotolerance. We established a synthetic scheme for the preparation of the peptide‐vitamin conjugates, which the chemically unstable vitamins tolerated. Among the obtained conjugates, the ATRA conjugate successfully suppressed inflammatory effects in macrophages and dendritic cells and induced antigen presentation in dendritic cells. This synthetic method of conjugate is conceivably applicable to other antigen peptides for induction of antigen‐specific immunotolerance.  相似文献   
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ABSTRACT

A newly identified chemical, 4-{3-[(3,5-dichloro-2-hydroxybenzylidene)amino]propyl}-4,5-dihydro-1H-pyrazol-5-one (BAPP) was characterized as a plant immunity activator. BAPP enhanced disease resistance in rice against rice blast disease and expression of a defense-related gene without growth inhibition. Moreover, BAPP was able to enhance disease resistance in dicotyledonous tomato and Arabidopsis plants against bacterial pathogen without growth inhibition, suggesting that BAPP could be a candidate as an effective plant activator. Analysis using Arabidopsis sid2-1 and npr1-2 mutants suggested that BAPP induced systemic acquired resistance (SAR) by stimulating between salicylic acid biosynthesis and NPR1, the SA receptor protein, in the SAR signaling pathway.  相似文献   
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Journal of Plant Research - Lianas have a huge influence on forest structure and function. However, it is unclear how the surrounding environment affects the establishment of liana seedlings in...  相似文献   
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Because of the high risk of going unnoticed, cryptic species represent a major challenge to biodiversity assessments, and this is particularly true for taxa that include many such species, for example, bats. Long‐eared bats from the genus Plecotus comprise numerous cryptic species occurring in the Mediterranean Region and present complex phylogenetic relationships and often unclear distributions, particularly at the edge of their known ranges and on islands. Here, we combine Species Distribution Models (SDMs), field surveys and molecular analyses to shed light on the presence of a cryptic long‐eared bat species from North Africa, Plecotus gaisleri, on the islands of the Sicily Channel, providing strong evidence that this species also occurs in Europe, at least on the islands of the Western Mediterranean Sea that act as a crossroad between the Old Continent and Africa. Species Distribution Models built using African records of P. gaisleri and projected to the Sicily Channel Islands showed that all these islands are potentially suitable for the species. Molecular identification of Plecotus captured on Pantelleria, and recent data from Malta and Gozo, confirmed the species' presence on two of the islands in question. Besides confirming that P. gaisleri occurs on Pantelleria, haplotype network reconstructions highlighted moderate structuring between insular and continental populations of this species. Our results remark the role of Italy as a bat diversity hotspot in the Mediterranean and also highlight the need to include P. gaisleri in European faunal checklists and conservation directives, confirming the usefulness of combining different approaches to explore the presence of cryptic species outside their known ranges—a fundamental step to informing conservation.  相似文献   
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Primates - In the original publication of the article, the coauthor “Takashi Hayakawa” was wrongly assigned as co-corresponding author.  相似文献   
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Escherichia coli YicI is a retaining α-xylosidase, which strictly recognizes the α-xylosyl moiety at the non-reducing end, belonging to glycoside hydrolase family 31 (GH 31). We have elucidated key residues determining the substrate specificity at both glycone and aglycone sites of Escherichia coli α-xylosidase (YicI). Detection of distinguishing features between α-xylosidases and α-glucosidases of GH 31 in their close evolutionary relationship has been used for the modification of protein function, converting YicI into an α-glucosidase. Aglycone specificity has been characterized by its transxylosylation ability. YicI exhibits a preference for aldopyranosyl sugars having equatorial 4-OH as the acceptor substrate with 1,6 regioselectivity, resulting in transfer products. The disaccharide transfer products of YicI, α-d-Xylp-(1→6)-d-Manp, α-d-Xylp-(1→6)-d-Fruf, and α-d-Xylp-(1→3)-d-Frup, are novel oligosaccharides, which have never been reported. The transxylosylation products are moderately inhibitory towards intestinal α-glucosidases.  相似文献   
240.
Previously we demonstrated that inhibition of replication-associated protein (Rep) binding to its replication origin by artificial zinc-finger proteins (AZPs) is a powerful method to prevent plant virus infection in vivo. In the present study, we applied the AZP technology to Tomato yellow leaf curl virus (TYLCV), which is a limiting factor in tomato cultivation worldwide. First, we determined 5′-ATCGGTGT ATCGGTGT-3′ in the 195-bp intergenic region of the TYLCV-Israel strain, a strain reported first among TYLCV strains, as the Rep-binding site by gel shift assays. We then constructed a 6-finger AZP that bound to a 19-bp DNA including the Rep-binding site. We demonstrated that the binding affinity of the AZP was >1,000-fold greater than that of Rep and that the AZP inhibited Rep binding completely in vitro. Because the binding capability of the AZP was same as that of the AZP previously designed for geminivirus-resistant Arabidopsis thaliana, we predict that the present AZP will prevent TYLCV infection in vivo.  相似文献   
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