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101.
102.
Xia Li Xiaomu Niu Ray A. Bressan Stephen C. Weller Paul M. Hasegawa 《In vitro cellular & developmental biology. Plant》1999,35(4):333-338
Summary Protocols and media constituents for efficient in vitro plant regeneration of Native Spearmint (Mentha spicata L. cultivar ‘Native Spearmint’) have been defined. Adventitious shoots were initiated either directly from morphogenetically
competent cells of explants or primary callus. Leaf explants from at least 2-mo.-old in vitro-maintained shoots exhibited
the greatest morphogenetic capacity. Explants derived from basal portions of leaves at the bottom of the shoot were most responsive,
with up to a 100% regeneration frequency and greater than nine shoots per explant. Highest frequency of meristemoids and morphogenetic
callus were initiated from explants cultured onto a basal medium containing Murashige and Skoog (MS) salts, supplemented with
4 mg thidiazuron (TDZ) per L and 25% (vol/vol) coconut water (CW) for 10 to 14 d in darkness. Bud and shoot development required
removal of both TDZ and CW from the medium. Shoot propagules were transferred to basal medium supplemented with 0.01 mg α-naphthaleneacetic
acid (NAA) per L and grown under low light for about 2 wk to facilitate shoot elongation. Individual shoots about 1 cm tall
were dissected and retransferred onto the same medium. Root initiation began within 4 to 6 d and a functional root system
developed within 2 to 3 wk. These plantlets were transferred to soil and acclimated successfully for growth and development
in a greenhouse. This is the first report of an efficient regeneration system for Native Spearmint based on adventitious organogenesis. 相似文献
103.
Angelo PC Nunes-Silva CG Brígido MM Azevedo JS Assunção EN Sousa AR Patrício FJ Rego MM Peixoto JC Oliveira WP Freitas DV Almeida ER Viana AM Souza AF Andrade EV Acosta PO Batista JS Walter ME Leomil L Anjos DA Coimbra RC Barbosa MH Honda E Pereira SS Silva A Pereira JO Silva ML Marins M Holanda FJ Abreu RM Pando SC Gonçalves JF Carvalho ML Leal-Mesquita ER da Silveira MA Batista WC Atroch AL França SC Porto JI Schneider MP 《Plant cell reports》2008,27(1):117-124
Guarana (Paullinia cupana var. sorbilis) is a plant native to the central Amazon basin. Roasted seed extracts have been used as medicinal beverages since pre-Colombian
times, due to their reputation as stimulants, aphrodisiacs, tonics, as well as protectors of the gastrointestinal tract. Guarana
plants are commercially cultivated exclusively in Brazil to supply the national carbonated soft-drink industry and natural
product stores around the world. In this report, we describe and discuss the annotation of 15,387 ESTs from guarana seeded-fruits,
highlighting sequences from the flavonoid and purine alkaloid pathways, and those related to biotic stress avoidance. This
is the largest set of sequences registered for the Sapindaceae family. 相似文献
104.
105.
Gustavo C. Bressan Eduardo C. Moraes Adriana O. Manfiolli Tais M. Kuniyoshi Dario O. Passos Marcelo D. Gomes Jörg Kobarg 《Cellular & molecular biology letters》2009,14(4):657-669
The human SFRS9/SRp30c belongs to the SR family of splicing regulators. Despite evidence that members of this protein family
may be targeted by arginine methylation, this has yet to be experimentally addressed. In this study, we found that SFRS9 is
a target for PRMT1-mediated arginine methylation in vitro, and that it is immunoprecipitated from HEK-293 lysates by antibodies that recognize both mono- and dimethylated arginines.
We further observed that upon treatment with the methylation inhibitor Adox, the fluorescent EGFP-SFRS9 re-localizes to dot-like
structures in the cell nucleus. In subsequent confocal analyses, we found that EGFP-SFRS9 localizes to nucleoli in Adox-treated
cells. Our findings indicate the importance of arginine methylation for the subnuclear localization of SFRS9. 相似文献
106.
Alberto Bressan Joel Arneodo Mauro Simonato William P. Haines Elisabeth Boudon‐Padieu 《Environmental microbiology》2009,11(12):3265-3279
Like other plant sap‐sucking insects, planthoppers within the family Cixiidae (Insecta: Hemiptera: Fulgoromorpha) host a diversified microbiota. We report the identification and first molecular characterization of symbiotic bacteria in cixiid planthoppers (tribe: Pentastirini). Using universal eubacterial primers we first screened the eubacterial 16S rRNA sequences in Pentastiridius leporinus (Linnaeus) with PCR amplification, cloning, and restriction fragment analysis. We identified three main 16S rRNA sequences that corresponded to a Wolbachia bacterium, a plant pathogenic bacterium, and a novel gammaproteobacterial symbiont. A fourth bacterial species affiliated with ‘Candidatus Sulcia muelleri’ was detected in PCR assays using primers specific for the Bacteroidetes. Within females of two selected cixiid planthoppers, P. leporinus and Oliarus filicicola, fluorescence In situ hybridization analysis and transmission electron microscopy observations showed that ‘Ca. Sulcia muelleri’ and the novel gammaproteobacterial symbiont were housed in separate bacteriomes. Phylogenetic analysis revealed that both of these symbionts occurred in at least four insect genera within the tribe Pentastirini. ‘Candidatus Purcelliella pentastirinorum’ was proposed as the novel gammaproteobacterial symbiont. 相似文献
107.
The dawn of plant salt tolerance genetics 总被引:12,自引:0,他引:12
108.
The planthopper Pentastiridius leporinus (L.) (Hemiptera: Cixiidae) has been identified as the main vector of 'Candidatus Arsenophonus phytopathogenicus', a plant pathogenic bacterium associated to a sugar beet disease in eastern France called syndrome 'basses richesses'. In a 2-yr survey (2006-07), we quantified the abundance of P. leporinus populations migrating into 29 sugar beet fields in eastern France. Sticky traps posted in these fields were monitored on a twice-weekly (2006) or weekly (2007) basis. Subsets of the captured planthoppers were tested for the presence of Ca. A. phytopathogenicus through polymerase chain reaction (PCR). Our results showed that planthoppers colonized sugar beet fields in June and July of each year, following temporal patterns of migration that were fitted to logistic functions. The number of planthoppers migrating into sugar beet fields greatly varied among the fields and the years surveyed, averaging from a few (2-10) to over 400 planthoppers per trap. Interestingly, the prevalence of planthoppers infected by Ca. A. phytopathogenicus increased nonlinearly with the abundance of planthoppers captured on the traps. The proportion of infection for Ca. A. phytopathogenicus ranged from ?0.07-1 (total infection) in small (2-10 planthoppers per trap) and large (400 planthoppers per trap) populations, respectively. We hypothesize that the outbreaks of P. leporinus in sugar beet fields, and the consequent increased rates of planthoppers infected by the Ca. A. phytopathogenicus, are key factors leading to the emergence of the sugar beet disease in eastern France. 相似文献
109.
Lei M Zhu C Liu Y Karthikeyan AS Bressan RA Raghothama KG Liu D 《The New phytologist》2011,189(4):1084-1095
? With the exception of root hair development, the role of the phytohormone ethylene is not clear in other aspects of plant responses to inorganic phosphate (Pi) starvation. ? The induction of AtPT2 was used as a marker to find novel signalling components involved in plant responses to Pi starvation. Using genetic and chemical approaches, we examined the role of ethylene in the regulation of plant responses to Pi starvation. ? hps2, an Arabidopsis mutant with enhanced sensitivity to Pi starvation, was identified and found to be a new allele of CTR1 that is a key negative regulator of ethylene responses. 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene, increases plant sensitivity to Pi starvation, whereas the ethylene perception inhibitor Ag+ suppresses this response. The Pi starvation-induced gene expression and acid phosphatase activity are also enhanced in the hps2 mutant, but suppressed in the ethylene-insensitive mutant ein2-5. By contrast, we found that ethylene signalling plays a negative role in Pi starvation-induced anthocyanin production. ? These findings extend the roles of ethylene in the regulation of plant responses to Pi starvation and will help us to gain a better understanding of the molecular mechanism underlying these responses. 相似文献
110.
Romão C Miranda CA Silva J Mandetta Clementino M de Filippis I Asensi M 《Current microbiology》2011,63(1):16-21
Biocides play an important role in healthcare-associated infection control by either minimizing or preventing microorganism
dissemination. This study evaluated the susceptibility of Pseudomonas aeruginosa clinical isolates to a quaternary ammonium (QAC) disinfectant and antibiotics, and verified the presence of qacEΔ1, a determinant of resistance to QAC. The disinfectant test was the Association of Official Analytical Chemists Use-Dilution
Test, and polymerase chain reaction was used to examine for qacEΔ1. The qacEΔ1 gene was detected in 48% of the isolates. Eighty-eight percent of the multiresistant isolates carried qacEΔ1 gene, while 35% of the non-multiresistant isolates was positive to this gene, and multiresistance well correlated with its
presence. Among isolates tested for the disinfectant, 46% showed a reduced susceptibility to the disinfectant. qacEΔ1 gene was present in 70% of the susceptible isolates to the biocide, whereas 90% of the less susceptible strains harbored
this gene. Reduced susceptibility to the disinfectant was independent of presence of qacEΔ1 suggesting that it does not play an important role in biocide resistance in P. aeruginosa. As far as we know, it is the first report confirming this fact and testing with disinfectant at its in-use concentration.
The evidence of less susceptible strains than the reference bacterium used in disinfectant testing, and the high percentage
of qacEΔ1 gene detected are of special concern and suggests continued investigation in laboratory and in situ, not only in healthcare
settings, but also in all areas of biocide usage, including different micro-organisms and biocides. 相似文献