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71.
Andreas Lackner Robert Sehlke Marius Garmhausen Giuliano Giuseppe Stirparo Michelle Huth Fabian TitzTeixeira Petra van der Lelij Julia Ramesmayer Henry F Thomas Meryem Ralser Laura Santini Elena Galimberti Mihail Sarov A Francis Stewart Austin Smith Andreas Beyer Martin Leeb 《The EMBO journal》2021,40(8)
72.
Andr Gomes-dos-Santos Manuel Lopes-Lima Andr M Machado Antnio Marcos Ramos Ana Usi Ivan N Bolotov Ilya V Vikhrev Sophie Breton L Filipe C Castro Rute R da Fonseca Juergen Geist Martin E
sterling Vincent Pri Amílcar Teixeira Han Ming Gan Oleg Simakov Elsa Froufe 《DNA research》2021,28(2)
Since historical times, the inherent human fascination with pearls turned the freshwater pearl mussel Margaritifera margaritifera (Linnaeus, 1758) into a highly valuable cultural and economic resource. Although pearl harvesting in M. margaritifera is nowadays residual, other human threats have aggravated the species conservation status, especially in Europe. This mussel presents a myriad of rare biological features, e.g. high longevity coupled with low senescence and Doubly Uniparental Inheritance of mitochondrial DNA, for which the underlying molecular mechanisms are poorly known. Here, the first draft genome assembly of M. margaritifera was produced using a combination of Illumina Paired-end and Mate-pair approaches. The genome assembly was 2.4 Gb long, possessing 105,185 scaffolds and a scaffold N50 length of 288,726 bp. The ab initio gene prediction allowed the identification of 35,119 protein-coding genes. This genome represents an essential resource for studying this species’ unique biological and evolutionary features and ultimately will help to develop new tools to promote its conservation. 相似文献
73.
Jean Carlos Cardoso Jaime A. Teixeira da Silva 《In vitro cellular & developmental biology. Plant》2013,49(6):710-716
Zeyheria montana Mart. has become endangered, primarily because of deforestation of its habitat, its use as a medicinal plant extract, and the strong endemism of the species. In this study, an efficient protocol was established for the micropropagation and conservation of Z. montana germplasm using isolated mature zygotic embryos as explants. Embryos germinated in vitro 4 d after isolation and inoculation on modified Murashige and Skoog (MS) medium containing 2.0 mg/l gibberellic acid (GA3). The addition of GA3 also improved the germination index and accelerated the process of germination. Nodal segments from seedlings were placed on modified ¼-strength MS medium containing 0.1 mg/l 6-benzyladenine and 0.5 mg/l GA3. Nodal segments produced 7.3 shoots per explant within 60 d. Following transfer of shoots to a medium containing 1.5 mg/l indole-3-butyric acid, roots formed. All plantlets obtained were successfully acclimatized under greenhouse conditions, and approximately 68.5 acclimatized plants could be obtained per seed each year. This protocol provides a method to preserve this rare and endangered medicinal plant. 相似文献
74.
K. A. Dutra V. Wanderley Teixeira G. S. Cruz C. T. S. Silva C. G. D´Assunção C. G. M. Ferreira 《Biotechnic & histochemistry》2013,88(7):498-513
ABSTRACTEssential oils are a promising alternative to insecticides. We investigated the LD50 of oils extracted from Piper corcovadensis, P. marginatum, and P. arboreum after 48 h topical contact with Spodoptera frugiperda larvae using morphometry, histochemistry and immunohistochemistry of the midgut and fat body. Chromatography revealed that E-caryophyllene was the principal compound common to the Piper species. The essential oils of P. corcovadensis, P. marginatum and P. arboreum caused deleterious changes in the midgut of S. frugiperda larvae. P. corcovadensis oil produced the lowest LD50 and significant histopathological alterations including elongation of the columnar cells, formation of cytoplasmic protrusions, reduction in carbohydrate, increased apoptotic index and decreased cell proliferation. P. arboreum oil caused histopathological alterations similar to P. corcovadensis, but caused the highest rate of cell proliferation and increased regenerative cells, which indicated rapid regeneration of the epithelium. Our findings demonstrated the insecticidal potential of P. corcovadensis for control of S. frugiperda owing to the significant damage it inflicted on S. frugiperda midgut. 相似文献
75.
Jaime A. Teixeira da Silva Judit Dobránszki Silvia Ross 《In vitro cellular & developmental biology. Plant》2013,49(1):1-16
In plant tissue culture research, there is a constant need to search for novel substances that could result in better or more efficient growth in vitro. A relatively unknown compound, phloroglucinol (1,3,5-trihydroxybenzene), which is a degradation product of phloridzin, has growth-promoting properties. Phloroglucinol increases shoot formation and somatic embryogenesis in several horticultural and grain crops. When added to rooting media together with auxin, phloroglucinol further stimulates rooting, most likely because phloroglucinol and its homologues act as auxin synergists or auxin protectors. Of particular interest is the ability of phloroglucinol—a precursor in the lignin biosynthesis pathway—to effectively control hyperhydricity through the process of lignification, thus maximizing the multiplication rate of woody species and other species that are difficult to propagate. Phloroglucinol has also been used to improve the recovery of cryopreserved Dendrobium protocorms, increasing the potential of cryopreservation for application in ornamental biotechnology. Phloroglucinol demonstrates both cytokinin-like and auxin-like activity, much like thidiazuron, and thus has considerable potential for application in a wide range of plant tissue culture studies. 相似文献
76.
77.
Mara Garcia Tavares Nathalia Teixeira Pietrani Maxwell de Castro Durvale Helder Canto Resende Lucio Antonio de Oliveira Campos 《Genetics and molecular biology》2013,36(1):111-117
Melipona quadrifasciata is a stingless bee widely found throughout the Brazilian territory, with two recognized subspecies, M. quadrifasciata anthidioides, that exhibits interrupted metasomal stripes, and M. quadrifasciata quadrifasciata, with continuous metasomal stripes. This study aimed to estimate the genetic variability of these subspecies. For this purpose, 127 colonies from 15 Brazilian localities were analyzed, using nine species-specific microsatellite primers. At these loci, the number of alleles ranged from three to 15 (mean: 7.2), and the observed heterozygosity (Ho) ranged from 0.03–0.21, while the expected heterozygosity (He) ranged from 0.23–0.47. The genetic distances among populations ranged from 0.03–0.45. The FST multilocus value (0.23) indicated that the populations sampled were structured, and the clustering analysis showed the formation of two subgroups and two more distant populations. The first group contained the subspecies M. quadrifasciata quadrifasciata, and the other, the subspecies M. quadrifasciata anthidioides and the two M. quadrifasciata populations with continuous metasomal stripes from northern Minas Gerais. These results confirmed that the yellow metasomal stripes alone are not a good means for correctly identifying the different subspecies of M. quadrifasciata. 相似文献
78.
79.
80.
Anderson Messias Rodrigues Marcus de Melo Teixeira G. Sybren de Hoog Tania Maria Pacheco Schubach Sandro Antonio Pereira Geisa Ferreira Fernandes Leila Maria Lopes Bezerra Maria Sueli Felipe Zoilo Pires de Camargo 《PLoS neglected tropical diseases》2013,7(6)
Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics of sporotrichosis occurred in Brazil due to zoonotic transmission, and cats were pointed out as key susceptible hosts. In order to understand the eco-epidemiology of feline sporotrichosis and its role in human sporotrichosis a survey was conducted among symptomatic cats. Prevalence and phylogenetic relationships among feline Sporothrix species were investigated by reconstructing their phylogenetic origin using the calmodulin (CAL) and the translation elongation factor-1 alpha (EF1α) loci in strains originated from Rio de Janeiro (RJ, n = 15), Rio Grande do Sul (RS, n = 10), Paraná (PR, n = 4), São Paulo (SP, n = 3) and Minas Gerais (MG, n = 1). Our results showed that S. brasiliensis is highly prevalent among cats (96.9%) with sporotrichosis, while S. schenckii was identified only once. The genotype of Sporothrix from cats was found identical to S. brasiliensis from human sources confirming that the disease is transmitted by cats. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii. No evidence of recombination in S. brasiliensis was found by split decomposition or PHI-test analysis, suggesting that S. brasiliensis is a clonal species. Strains recovered in states SP, MG and PR share the genotype of the RJ outbreak, different from the RS clone. The occurrence of separate genotypes among strains indicated that the Brazilian S. brasiliensis epidemic has at least two distinct sources. We suggest that cats represent a major host and the main source of cat and human S. brasiliensis infections in Brazil. 相似文献