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961.
Fabieli Loise Braga Feitosa Bianca Ferreira Olivieri Carolyn Aboujaoude Angélica Simone Cravo Pereira Marcos Vinicius Antunes de Lemos Hermenegildo Lucas Justino Chiaia Mariana Piatto Berton Elisa Peripolli Adrielle Matias Ferrinho Lenise Freitas Mueller Mônica Roberta Mazalli Lucia Galvão de Albuquerque Henrique Nunes de Oliveira Humberto Tonhati Rafael Espigolan Rafael Lara Tonussi Rafael Medeiros de Oliveira Silva Daniel Gustavo Mansan Gordo Ana Fabrícia Braga Magalhães Ignacio Aguilar Fernando Baldi 《Journal of applied genetics》2017,58(1):123-132
The objective of this study was to estimate the genetic–quantitative relationships between the beef fatty acid profile with the carcass and meat traits of Nellore cattle. A total of 1826 bulls finished in feedlot conditions and slaughtered at 24 months of age on average were used. The following carcass and meat traits were analysed: subcutaneous fat thickness (BF), shear force (SF) and total intramuscular fat (IMF). The fatty acid (FA) profile of the Longissimus thoracis samples was determined. Twenty-five FAs (18 individuals and seven groups of FAs) were selected due to their importance for human health. The animals were genotyped with the BovineHD BeadChip and, after quality control for single nucleotide polymorphisms (SNPs), only 470,007 SNPs from 1556 samples remained. The model included the random genetic additive direct effect, the fixed effect of the contemporary group and the animal’s slaughter age as a covariable. The (co)variances and genetic parameters were estimated using the REML method, considering an animal model (single-step GBLUP). A total of 25 multi-trait analyses, with four traits, were performed considering SF, BF and IMF plus each individual FA. The heritability estimates for individual saturated fatty acids (SFA) varied from 0.06 to 0.65, for monounsaturated fatty acids (MUFA) it varied from 0.02 to 0.14 and for polyunsaturated fatty acids (PUFA) it ranged from 0.05 to 0.68. The heritability estimates for Omega 3, Omega 6, SFA, MUFA and PUFA sum were low to moderate, varying from 0.09 to 0.20. The carcass and meat traits, SF (0.06) and IMF (0.07), had low heritability estimates, while BF (0.17) was moderate. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with BF were 0.04, 0.64 and ?0.41, respectively. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with SF were 0.29, ?0.06 and ?0.04, respectively. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with IMF were 0.24, 0.90 and ?0.67, respectively. The selection to improve meat tenderness in Nellore cattle should not change the fatty acid composition in beef, so it is possible to improve this attribute without affecting the nutritional beef quality in zebu breeds. However, selection for increased deposition of subcutaneous fat thickness and especially the percentage of intramuscular fat should lead to changes in the fat composition, highlighting a genetic antagonism between meat nutritional value and acceptability by the consumer. 相似文献
962.
Romel Gonzales-Salazar Bianca Cecere Michelina Ruocco Rosa Rao Giandomenico Corrado 《Biotechnology letters》2017,39(7):1049-1058
Objectives
To engineer broad spectrum resistance in potato using different expression strategies.Results
The previously identified Ribosome-Inactivating Protein from Phytolacca heterotepala was expressed in potato under a constitutive or a wound-inducible promoter. Leaves and tubers of the plants constitutively expressing the transgene were resistant to Botrytis cinerea and Rhizoctonia solani, respectively. The wound-inducible promoter was useful in driving the expression upon wounding and fungal damage, and conferred resistance to B. cinerea. The observed differences between the expression strategies are discussed considering the benefits and features offered by the two systems.Conclusions
Evidence is provided of the possible impact of promoter sequences to engineer BSR in plants, highlighting that the selection of a suitable expression strategy has to balance specific needs and target species.963.
Frantzeskos?Papanikos Katrin?Daniel Angelique?Goercharn-Ramlal Ji-Feng?Fei Thomas?Kurth Lukasz?Wojtasz Ihsan?Dereli Jun?Fu Josef?Penninger Bianca?Habermann Azim?Surani A.?Francis?Stewart Attila?TothEmail author 《Chromosoma》2017,126(3):399-415
Meiosis is a critical phase in the life cycle of sexually reproducing organisms. Chromosome numbers are halved during meiosis, which requires meiosis-specific modification of chromosome behaviour. Furthermore, suppression of transposons is particularly important during meiosis to allow the transmission of undamaged genomic information between generations. Correspondingly, specialized genome defence mechanisms and nuclear structures characterize the germ line during meiosis. Survival of mammalian spermatocytes requires that the sex chromosomes form a distinct silenced chromatin domain, called the sex body. An enigmatic spherical DNA-negative structure, called the meiotic dense body, forms in association with the sex body. The dense body contains small non-coding RNAs including microRNAs and PIWI-associated RNAs. These observations gave rise to speculations that the dense body may be involved in sex body formation and or small non-coding RNA functions, e.g. the silencing of transposons. Nevertheless, the function of the dense body has remained mysterious because no protein essential for dense body formation has been reported yet. We discovered that the polycomb-related sex comb on midleg-like 1 (SCML1) is a meiosis-specific protein and is an essential component of the meiotic dense body. Despite abolished dense body formation, Scml1-deficient mice are fertile and proficient in sex body formation, transposon silencing and in timely progression through meiosis and gametogenesis. Thus, we conclude that dense body formation is not an essential component of the gametogenetic program in the mammalian germ line. 相似文献
964.
965.
Edieidia S. Pina Juliana S. Coppede Silvia H. Taleb Contini Eduardo J. Crevelin Luciano M. Lião Bianca W. Bertoni Suzelei C. França Ana Maria S. Pereira 《Plant Cell, Tissue and Organ Culture》2017,128(3):705-714
Quinone-methide triterpenoids (QMTs) derived from species of the family Celastraceae have long been used as anti-cancer, anti-inflammatory, anti-oxidant, anti-malarial and insecticidal agents. The main problem in producing QMTs on a large-scale from natural sources is the low amounts (<0.4% dry weight) produced by plants grown in vivo. The aim of this study was to compare the levels of QMTs accumulated by roots of Cheiloclinium cognatum cultured in vitro with those of in vivo plants aged 6 months to 10 years. The highest levels of QMTs produced by in vivo specimens were found in root bark of 10-year old plants, but in vitro cultured roots produced 3.52-times more 22β-hydroxy-maytenin and 11.46-times more maytenin. Most importantly, the cultured roots excreted QMTs into the growth medium, thereby facilitating the large-scale production, extraction and purification of these bioactive compounds by means of a continuous and non-destructive bioprocess that would preserve the root cultures. 相似文献
966.
Dominic Barthelmes Katja Barthelmes Kai Schnorr Hendrik R. A. Jonker Bianca Bodmer Karen N. Allen Barbara Imperiali Harald Schwalbe 《Journal of biomolecular NMR》2017,68(3):187-194
Encodable lanthanide binding tags (LBTs) have become an attractive tool in modern structural biology as they can be expressed as fusion proteins of targets of choice. Previously, we have demonstrated the feasibility of inserting encodable LBTs into loop positions of interleukin-1β (Barthelmes et al. in J Am Chem Soc 133:808–819, 2011). Here, we investigate the differences in fast dynamics of selected loop-LBT interleukin-1β constructs by measuring 15N nuclear spin relaxation experiments. We show that the loop-LBT does not significantly alter the dynamic motions of the host protein in the sub-τc-timescale and that the loop-LBT adopts a rigid conformation with significantly reduced dynamics compared to the terminally attached encodable LBT leading to increased paramagnetic alignment strength. We further analyze residual dipolar couplings (RDCs) obtained by loop-LBTs and additional liquid crystalline media to assess the applicability of the loop-LBT approach for RDC-based methods to determine structure and dynamics of proteins, including supra-τc dynamics. Using orthogonalized linear combinations (OLCs) of RDCs and Saupe matrices, we show that the combined use of encodable LBTs and external alignment media yields up to five linear independent alignments. 相似文献
967.
968.
Shigeru Kanda Takefumi Shono Bianca Tomasini-Johansson Peter Klint Yutaka Saito 《Experimental cell research》1999,252(2):262-272
Angiogenesis involves proliferation of capillary endothelial cells and formation of lumen-containing tube-like structures. A recently established murine brain capillary endothelial cell line, IBE, can either proliferate or form tube-like structures (i.e., differentiate) in response to fibroblast growth factor-2 (FGF-2), dependent on the culture conditions. The 4N1K peptide (KRFYVVMWKK), which is derived from the C-terminal cell-binding domain of thrombospondin-1 (TSP-1), inhibited tube formation, but not proliferation of IBE cells. Polyclonal antibodies against 4N1K blocked TSP-1-induced inhibition of tube formation by IBE cells. 4N1K inhibited tyrosine phosphorylation of focal adhesion kinase and FGF-2-stimulated tyrosine phosphorylation of phospholipase C-gamma in tube-forming, but not proliferating, IBE cells. The peptide also inhibited FGF-2-induced neovascularization in mouse cornea. Our results indicate that TSP-1 may exert its inhibitory effects on angiogenesis via the C-terminal cell-binding domain containing the 4N1K sequence by inhibiting tube formation by endothelial cells. 相似文献
969.
Although the tyramine amplification technique to enhance sensitivity in immunohistochemistry has been described in numerous methodological papers, it has not yet gained access to diagnostic immunohistochemistry. This is mainly due to problems and pitfalls occurring in adaptation of this method to routine application.In this study a monoclonal antibody and a polyclonal antiserum (pan-cytokeratin and anti-myoglobin) were tested in tissues with different amounts of epitopes, using a checkerboard table and testing a total of 133 different dilution combinations of both the tyramide solution and the primary antibodies.The specific tissue investigated, i.e. the amount of accessable epitope to be detected and the applied concentration of the tyramide solution mainly influenced the staining reaction. Several pitfalls such as an uneven distribution of the staining or dramatic overstaining (paradoxical overstaining) must be considered to achieve optimal results.In conclusion, our data confirm methodological studies that the tyramine amplification technique is a powerful method to enhance immunohistochemical sensitivity. However, for reliable daily practice several pitfalls of the technique have to be circumvented. 相似文献
970.
Improved Secretion of Native Human Insulin-Like Growth Factor 1 from gas1 Mutant Saccharomyces cerevisiae Cells
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Marina Vai Luca Brambilla Ivan Orlandi Nicola Rota Bianca Maria Ranzi Lilia Alberghina Danilo Porro 《Applied microbiology》2000,66(12):5477-5479
We studied the secretion of recombinant human insulin-like growth factor 1 (rhIGF-1) from transformed yeast cells. The hIGF-1 gene was fused to the mating factor α prepro- leader sequence under the control of the constitutive ACT1 promoter. We found that the inactivation of the GAS1 gene in the host strain led to a supersecretory phenotype yielding a considerable increase, from 8 to 55 mg/liter, in rhIGF-1 production. 相似文献