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In the present study, an efficient system for the in vitro regeneration of adventitious shoots from the peach rootstock Hansen 536 leaves has been established. Twenty regeneration media containing McCown Woody Plant Medium (WPM) as a basal salt supplemented with different concentrations and combinations of plant growth regulators (PGRs) were tested. Expanded leaves along with their petiole from 3-week-old elongated in vitro shoot cultures were used as starting explants. The highest regeneration rate (up to 53%) was obtained on WPM basal medium enriched with 15.5 &mu, M N6-benzylaminopurine (BAP). The influences on leaf regeneration of the ethylene inhibitor silver thiosulphate (STS) and of different combinations of antibiotics added to the optimized regeneration medium were also investigated. The use of 10 &mu, M STS or carbenicillin (238 mM) combined with cefotaxime (210 &mu, M) significantly increased the average number of regenerating shoots per leaf compared to the control. In vitro shoots were finally elongated, rooted and successfully acclimatized in the greenhouse. The results achieved in this study advances the knowledge on factors affecting leaf organogenesis in Prunus spp., and the regeneration protocol described looks promising for the optimization of new genetic transformation procedures in Hansen 536 and other peach rootstocks and cultivars.

Aim: Aim of the present study was to carry out the partial purification and biochemical characterization of glutathione S-transferase (GST) from the somatic tissue of ruminal amphistome parasite, Gastrothylax crumenifer (Gc) infecting Indian water buffalo (Bubalus bubalis). Materials and Methods: The crude somatic homogenate of Gc was subjected to progressive ammonium sulfate precipitation followed by size exclusion chromatography in a Sephacryl S 100-HR column. The partially purified GST was assayed spectrophotometrically, and the corresponding enzyme activity was also recorded in polyacrylamide gel. GST isolated from the amphistome parasite was also exposed to variable changes in temperature and the pH gradient of the assay mixture. Results: The precipitated amphistome GST molecules showed maximum activity in the sixth elution fraction. The GST subunit appeared as a single band in the reducing polyacrylamide gel electrophoresis with an apparent molecular weight of 26 kDa. The GST proteins were found to be fairly stable up to 37°C, beyond this the activity got heavily impaired. Further, the GST obtained showed a pH optima of 7.5. Conclusion: Present findings showed that GST from Gc could be conveniently purified using gel filtration chromatography. The purified enzyme showed maximum stability and activity at 4°C.

Plant regeneration in vitro from virus-infected somatic tomato (Lycopersicon sp.) tissue was performed. Regeneration experiments were started after the determination of virus presence, using enzyme-linked immunosorbent assay, in leaves used as a source of explants. Leaf explants infected with selected strains of tomato mosaic Tobamovirus or cucumber mosaic Cucumovirus respectively, were cultured on a standarised MS agar medium to induce adventitious shoots, which were afterwards excised, rooted in vitro and cultured to plants. Explants were also screened for their ability to produce callus. Diverse effects of viral infection, ranging from stimulation to inhibition of callus formation and of morphogenesis rate, were observed. The health condition of the tissue proved to affect regeneration potential of Lycopersicon esculentum, whereas wild accesions did not react in that case so distinctly. In cultivated tomato was encountered the decline in competence to reproduce shoots adventitiously in infected tissue. There was also relationship between donor plant health condition and adventitious root formation in regenerated shoots. Experiments with short-term cultures of L. esculenum reveled also that a certain number of shoots regenerated from diseased tissue can be virus-free.

The maintenance of metabolic activities during the in vitro culture of somatic cells of wild animals, especially collared peccary (Pecari tajacu), is an interesting step in conservation of these cells for the use in nuclear transfer. In this context, it is necessary to optimize the culture conditions of somatic cells by the establishment of appropriate supplementation to the media. Therefore, this study aimed to analyze the composition of the culture means of somatic cell derived from ear tissue of collared peccaries, evaluating concentrations of fetal bovine serum (FBS; 10% vs. 20%) and epidermal growth factor (EGF; 5ng/mL vs. 10ng/mL). Tissues were submitted to primary culture and subcultures for 40 days and cells were analyzed for morphology, adhesion, subconfluence, and proliferative activity to develop the growth curve and to determine the population doubling time (PDT), viability, and functional/metabolic activity. No difference was observed between the concentrations of FBS for several parameters, except for viability [FBS10: 85.6% vs. FBS20: 98.2%], PDT [FBS10: 155.4h vs. 77.2h], and functional/metabolic assay [FBS10: 0.57-0.55 vs. FBS20: 0.82-0.99 (D5-D7)]. For the EGF in culture, no difference was observed in the evaluated parameters. In all experiments, the growth curves were typical S-shape and the cells passed through a lag, logarithmic, and plateau phase. In conclusion, 20% FBS is suitable for the recovery of somatic cells; nevertheless, EGF does not improve the quality of growing these cells. To our knowledge, this is the first study culturing somatic cells of collared peccaries. RESUMO: A manutenção das atividades metabólicas durante o cultivo in vitro de células somáticas de animais silvestres, especialmente cateto (Pecari tajacu), é uma etapa interessante na conservação dessas células para o uso na transferência nuclear. Nesse contexto, é necessário aperfeiçoar as condições de cultivo de células somáticas pelo estabelecimento de suplementações apropriadas aos meios. Portanto, este estudo objetivou analisar a composição dos meios de cultivo de células somáticas derivadas de tecido auricular de catetos, avaliando concentrações de soro fetal bovino (SFB; 10% vs. 20%) e fator de crescimento epidermal (EGF; 5 ng/mL vs. 10 ng/mL). Para tanto, tecidos foram submetidos ao cultivo primário e subcultivos por 40 dias e células foram analisadas por morfologia, adesão, subconfluência, e atividade proliferativa pelo desenvolvimento da curva de crescimento e determinação do time de duplicação da população (PDT), viabilidade, e atividade funcional/metabólica. Nenhuma diferença foi observada entre as concentrações de SFB para os vários parâmetros, exceto para viabilidade [SFB10: 85,6% vs. SFB20: 98,2%], PDT [SFB10: 155,4 h vs. 77,2 h], e atividade funcional/metabólica [SFB10: 0,57-0,55 vs. SFB20: 0,82-0,99 (D5-D7)]. Para o EGF em cultivo, nenhuma diferença foi observada nos parâmetros avaliados. Em todos os experimentos, as curvas de crescimento foram típicas de forma S e as células passaram por uma fase lag, logarítmica e platô. Em conclusão, 20% de SFB é adequado para a recuperação de células somáticas; contudo, EGF não melhora a qualidade de crescimento dessas células. Ao nosso conhecimento, este é o primeiro estudo cultivando células somáticas de catetos.

Background As a major epigenetic component, DNA methylation plays important functions in individual development and various diseases. DNA methylation has been well studied in human and model organisms, but only limited data exist in economically important animals like cattle. Results Using reduced representation bisulphite sequencing (RRBS), we obtained single-base-resolution maps of bovine DNA methylation from ten somatic tissues. In total, we evaluated 1,868,049 cytosines in CG-enriched regions. While we found slightly low methylation levels (29.87 to 38.06 %) in cattle, the methylation contexts (CGs and non-CGs) of cattle showed similar methylation patterns to other species. Non-CG methylation was detected but methylation levels in somatic tissues were significantly lower than in pluripotent cells. To study the potential function of the methylation, we detected 10,794 differentially methylated cytosines (DMCs) and 836 differentially methylated CG islands (DMIs). Further analyses in the same tissues revealed many DMCs (including non-CGs) and DMIs, which were highly correlated with the expression of genes involved in tissue development. Conclusions In summary, our study provides a baseline dataset and essential information for DNA methylation profiles of cattle. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3116-1) contains supplementary material, which is available to authorized users.