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排序方式: 共有197条查询结果,搜索用时 15 毫秒
11.
Gemma Molero Ryan Joynson Francisco J. Pinera‐Chavez Laura‐Jayne Gardiner Carolina Rivera‐Amado Anthony Hall Matthew P. Reynolds 《Plant biotechnology journal》2019,17(7):1276-1288
One of the major challenges for plant scientists is increasing wheat (Triticum aestivum) yield potential (YP). A significant bottleneck for increasing YP is achieving increased biomass through optimization of radiation use efficiency (RUE) along the crop cycle. Exotic material such as landraces and synthetic wheat has been incorporated into breeding programmes in an attempt to alleviate this; however, their contribution to YP is still unclear. To understand the genetic basis of biomass accumulation and RUE, we applied genome‐wide association study (GWAS) to a panel of 150 elite spring wheat genotypes including many landrace and synthetically derived lines. The panel was evaluated for 31 traits over 2 years under optimal growing conditions and genotyped using the 35K wheat breeders array. Marker‐trait association identified 94 SNPs significantly associated with yield, agronomic and phenology‐related traits along with RUE and final biomass (BM_PM) at various growth stages that explained 7%–17% of phenotypic variation. Common SNP markers were identified for grain yield, BM_PM and RUE on chromosomes 5A and 7A. Additionally, landrace and synthetic derivative lines showed higher thousand grain weight (TGW), BM_PM and RUE but lower grain number (GM2) and harvest index (HI). Our work demonstrates the use of exotic material as a valuable resource to increase YP. It also provides markers for use in marker‐assisted breeding to systematically increase BM_PM, RUE and TGW and avoid the TGW/GM2 and BM_PM/HI trade‐off. Thus, achieving greater genetic gains in elite germplasm while also highlighting genomic regions and candidate genes for further study. 相似文献
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María?Laura?VidozEmail author Hebe?Yolanda?Rey Ana?María?Gonzalez Luis?Amado?Mroginski 《Acta Physiologiae Plantarum》2004,26(1):59-66
Plants of two accessions of Arachis glabrata were regenerated via somatic embryogenesis. Embryogenic calli were initiated from leaflet explants on Murashige and Skoog medium supplemented
with picloram alone or picloram in combination with 6-benzylaminopurine. Leaflets of accession A6138 induced the highest percentage
of somatic embryos in media composed of 10 mg dm−3 and 15 mg dm−3 picloram. In contrast, 5 mg dm−3 picloram with 0.1 mg dm−3 6-benzylaminopurine was one of the most effective combinations in accession AF385. MS medium supplemented with 2 g dm−3 activated charcoal (AC) used for 30 days was the most effective for embryo maturation. After 20 days of culture on MS medium
devoid of growth regulators, 6 % of embryos converted into plantlets in accession A6138. 相似文献
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Rita Ferreira Rui Vitorino Renato M. P. Alves Hans Joachim Appell Scott K. Powers José Alberto Duarte Francisco Amado 《Proteomics》2010,10(17):3142-3154
Skeletal muscle is a highly specialized tissue that contains two distinct mitochondria subpopulations, the subsarcolemmal (SS) and the intermyofibrillar (IMF) mitochondria. Although it is established that these mitochondrial subpopulations differ functionally in several ways, limited information exists about the proteomic differences underlying these functional differences. Therefore, the objective of this study was to biochemically characterize the SS and IMF mitochondria isolated from rat red gastrocnemius skeletal muscle. We separated the two mitochondrial subpopulations from skeletal muscle using a refined method that provides an excellent division of these unique mitochondrial subpopulations. Using proteomics of mitochondria and its subfractions (intermembrane space, matrix and inner membrane), a total of 325 distinct proteins were identified, most of which belong to the functional clusters of oxidative phosphorylation, metabolism and signal transduction. Although more gel spots were observed in SS mitochondria, 38 of the identified proteins were differentially expressed between the SS and IMF subpopulations. Compared to the SS mitochondrial, IMF mitochondria expressed a higher level of proteins associated with oxidative phosphorylation. This observation, coupled with the finding of a higher respiratory chain complex activity in IMF mitochondria, suggests a specialization of IMF mitochondria toward energy production for contractile activity. 相似文献
16.
Aims: To compare three methods for DNA extraction from Mycobacterium bovis , Mycobacterium tuberculosis and Mycobacterium avium subsp. avium .
Methods and Results: The DNA was extracted from mycobacterial cultures using enzymatic extraction, combined bead beating and enzymatic extraction and cetyltrimethylammonium bromide (CTAB) extraction. The yield and quality of DNA were compared by spectrophotometry, agarose gel electrophoresis, restriction endonuclease analysis and PCR. The combined bead beating and enzymatic extraction method yielded more DNA. However, that method produced some sheared DNA, visible either by agarose gel electrophoresis or by restriction endonuclease analysis. All methods were appropriate for PCR amplification of a 123 bp fragment of IS 6110 in M. bovis and M. tuberculosis , and of a 1700 bp fragment of FR300 region in M. avium avium .
Conclusions: Combined bead beating and enzymatic extraction method was the most efficient and easy method for extracting DNA from bacteria of the M. tuberculosis complex.
Significance and Impact of the Study: The results reveal important differences among the DNA extraction methods for mycobacteria, which are relevant for the success of further downstream molecular analysis. 相似文献
Methods and Results: The DNA was extracted from mycobacterial cultures using enzymatic extraction, combined bead beating and enzymatic extraction and cetyltrimethylammonium bromide (CTAB) extraction. The yield and quality of DNA were compared by spectrophotometry, agarose gel electrophoresis, restriction endonuclease analysis and PCR. The combined bead beating and enzymatic extraction method yielded more DNA. However, that method produced some sheared DNA, visible either by agarose gel electrophoresis or by restriction endonuclease analysis. All methods were appropriate for PCR amplification of a 123 bp fragment of IS 6110 in M. bovis and M. tuberculosis , and of a 1700 bp fragment of FR300 region in M. avium avium .
Conclusions: Combined bead beating and enzymatic extraction method was the most efficient and easy method for extracting DNA from bacteria of the M. tuberculosis complex.
Significance and Impact of the Study: The results reveal important differences among the DNA extraction methods for mycobacteria, which are relevant for the success of further downstream molecular analysis. 相似文献
17.
Leonardo Tavares Salgado Leonardo Paes Cinelli Nathan Bessa Viana Rodrigo Tomazetto de Carvalho Paulo Antônio De Souza Mourão Valéria Laneuville Teixeira Marcos Farina And Gilberto Menezes Amado Filho 《Journal of phycology》2009,45(1):193-202
The interaction between phenolic substances (PS) and alginates (ALG) has been suggested to play a role in the structure of the cell walls of brown seaweeds. However, no clear evidence for this interaction was reported. Vanadium bromoperoxidase (VBPO) has been proposed as a possible catalyst for the binding of PS to ALG. In this work, we studied the interaction between PS and ALG from brown algae using size exclusion chromatography (SEC) and optical tweezers microscopy. The analysis by SEC revealed that ALG forms a high‐molecular‐weight complex with PS. To study the formation of this molecular complex, we investigated the in vitro interaction of purified ALG from Fucus vesiculosus L. with purified PS from Padina gymnospora (Kütz.) Sond., in the presence or absence of VBPO. The interaction between PS and ALG only occurred when VBPO was added, indicating that the enzyme is essential for the binding process. The interaction of these molecules led to a reduction in ALG viscosity. We propose that VBPO promotes the binding of PS molecules to the ALG uronic acids residues, and we also suggest that PS are components of the brown algal cell walls. 相似文献
18.
Moreira-Gonçalves D Henriques-Coelho T Fonseca H Ferreira RM Amado F Leite-Moreira A Duarte JA 《American journal of physiology. Heart and circulatory physiology》2011,300(3):H1044-H1052
The present study evaluated the impact of moderate exercise training on the cardiac tolerance to acute pressure overload. Male Wistar rats were randomly submitted to exercise training or sedentary lifestyle for 14 wk. At the end of this period, the animals were anaesthetized, mechanically ventilated, and submitted to hemodynamic evaluation with biventricular tip pressure manometers. Acute pressure overload was induced by banding the descending aorta to induce a 60% increase of peak systolic left ventricular pressure during 120 min. This resulted in the following experimental groups: 1) sedentary without banding (SED + Sham), 2) sedentary with banding (SED + Band), and 3) exercise trained with banding (EX + Band). In response to aortic banding, SED + Band animals could not sustain the 60% increase of peak systolic pressure for 120 min, even with additional narrowing of the banding. This was accompanied by a reduction of dP/dt(max) and dP/dt(min) and a prolongation of the time constant tau, indicating impaired systolic and diastolic function. This impairment was not observed in EX + Band (P < 0.05 vs. SED + Band). Additionally, compared with SED + Band, EX + Band presented less myocardial damage, exhibited attenuated protein expression of active caspase-3 and NF-κB (P < 0.016), and showed less protein carbonylation and nitration (P < 0.05). These findings support our hypothesis that exercise training has a protective role in the modulation of the early cardiac response to pressure overload. 相似文献
19.
Fedatto Júnior Z Ishii-Iwamoto EL Amado CB Vicentini GE Panerari AD Bracht A Kelmer-Bracht AM 《Cell biochemistry and function》1999,17(4):271-278
The gluconeogenic response in the liver from rats with chronic arthritis to various substrates and the effects of glucagon were investigated. The experimental technique used was the isolated liver perfusion. Hepatic gluconeogenesis in arthritic rats was generally lower than in normal rats. The difference between normal and arthritic rats depended on the gluconeogenic substrate. In the absence of glucagon the following sequence of decreasing differences was found: alanine (-71.8 per cent) reverse similarglutamine (-71.7 per cent)>pyruvate (-60 per cent)>lactate+pyruvate (-44.9 per cent)>xylitol (n.s.=non-significant) reverse similarglycerol (n.s.). For most substrates glucagon increased hepatic gluconeogenesis in both normal and arthritic rats. The difference between normal and arthritic rats, however, tended to diminish, as revealed by the data of the following sequence: alanine (-48.9 per cent) reverse similarpyruvate (-47.6 per cent)>glutamine (-33.8 per cent)>glycerol (n.s.) reverse similarlactate+pyruvate (n.s.) reverse similarxylitol (n.s.). The causes for the reduced hepatic gluconeogenesis in arthritic rats are probably related to: (a) lower activities of key enzymes catalyzing most probably steps preceding phosphoenolpyruvate (e.g. phosphoenolpyruvate carboxykinase, pyruvate carboxylase, etc. ); (b) a reduced availability of reducing equivalents in the cytosol; (c) specific differences in the situations induced by hormones or by the individual substrates. Since glycaemia is almost normal in chronically arthritic rats, it seems that lower gluconeogenesis is actually adapted to the specific needs of these animals. 相似文献
20.
Ana Paula Ribeiro Silvia Maria Amado Jo?o Roberto Casanova Dinato Vitor Daniel Tessutti Isabel Camargo Neves Sacco 《PloS one》2015,10(9)