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291.
Andreia Bufalino Nilva K. Cervigne Carine Ervolino de Oliveira Felipe Paiva Fonseca Priscila Campioni Rodrigues Carolina Carneiro Soares Macedo Lays Martin Sobral Marcia Costa Miguel Marcio Ajudarte Lopes Adriana Franco Paes Leme Daniel W. Lambert Tuula A. Salo Luiz Paulo Kowalski Edgard Graner Ricardo D. Coletta 《PloS one》2015,10(8)
Deregulated expression of activin A is reported in several tumors, but its biological functions in oral squamous cell carcinoma (OSCC) are unknown. Here, we investigate whether activin A can play a causal role in OSCCs. Activin A expression was assessed by qPCR and immunohistochemistry in OSCC tissues. Low activin A-expressing cells were treated with recombinant activin A and assessed for apoptosis, proliferation, adhesion, migration, invasion and epithelial-mesenchymal transition (EMT). Those phenotypes were also evaluated in high activin A-expressing cells treated with follistatin (an activin A antagonist) or stably expressing shRNA targeting activin A. Transfections of microRNA mimics were performed to determine whether the overexpression of activin A is regulated by miR-143/miR-145 cluster. Activin A was overexpressed in OSCCs in comparison with normal oral mucosa, and high activin A levels were significantly associated with lymph node metastasis, tumor differentiation and poor survival. High activin A levels promoted multiple properties associated with malignant transformation, including decreased apoptosis and increased proliferation, migration, invasion and EMT. Both miR-143 and miR-145 were markedly downregulated in OSCC cell lines and in clinical specimens, and inversely correlated to activin A levels. Forced expression of miR-143 and miR-145 in OSCC cells significantly decreased the expression of activin A. Overexpression of activin A in OSCCs, which is controlled by downregulation of miR-143/miR-145 cluster, regulates apoptosis, proliferation and invasiveness, and it is clinically correlated with lymph node metastasis and poor survival. 相似文献
292.
293.
Katja Jouhikainen Laura Lindgren Tuula Jokelainen Raimo Hiltunen Teemu H. Teeri Kirsi-Marja Oksman-Caldentey 《Planta》1999,208(4):545-551
In order to test the possibility of enhancing the production of pharmaceutically valuable scopolamine in transgenic cultures,
the 35S-h6h transgene that codes for the enzyme hyoscyamine-6β-hydroxylase (EC 1.14.11.11) was introduced into Hyoscyamus muticus L. strain Cairo (Egyptian henbane). This plant was chosen for its capability to produce very high amounts of tropane alkaloids
(up to 6% of the dry weight in the leaves of mature plant). To our knowledge, this is the first time such a large population
of transgenic cultures has been studied at the morphological, chemical and genetic levels. A great variation was observed
in the tropane alkaloid production among the 43 positive transformants. The best clone (KB7) produced 17 mg/l scopolamine,
which is over 100 times more than the control clones. However, conversion of hyoscyamine to scopolamine was still incomplete.
The expression of h6h was found to be proportional to the scopolamine production, and was the main reason behind the variation in the scopolamine/hyoscyamine
ratio in the hairy-root clones. These results indicate that H. muticus strain Cairo has a potential for even more enhanced scopolamine production with more efficient gene-expression systems.
Received: 24 December 1998 / Accepted: 13 January 1999 相似文献
294.
295.
Adriana Giongo Kelsey A Gano David B Crabb Nabanita Mukherjee Luis L Novelo George Casella Jennifer C Drew Jorma Ilonen Mikael Knip Heikki Hy?ty Riitta Veijola Tuula Simell Olli Simell Josef Neu Clive H Wasserfall Desmond Schatz Mark A Atkinson Eric W Triplett 《The ISME journal》2011,5(1):82-91
Several studies have shown that gut bacteria have a role in diabetes in murine models. Specific bacteria have been correlated with the onset of diabetes in a rat model. However, it is unknown whether human intestinal microbes have a role in the development of autoimmunity that often leads to type 1 diabetes (T1D), an autoimmune disorder in which insulin-secreting pancreatic islet cells are destroyed. High-throughput, culture-independent approaches identified bacteria that correlate with the development of T1D-associated autoimmunity in young children who are at high genetic risk for this disorder. The level of bacterial diversity diminishes overtime in these autoimmune subjects relative to that of age-matched, genotype-matched, nonautoimmune individuals. A single species, Bacteroides ovatus, comprised nearly 24% of the total increase in the phylum Bacteroidetes in cases compared with controls. Conversely, another species in controls, represented by the human firmicute strain CO19, represented nearly 20% of the increase in Firmicutes compared with cases overtime. Three lines of evidence are presented that support the notion that, as healthy infants approach the toddler stage, their microbiomes become healthier and more stable, whereas, children who are destined for autoimmunity develop a microbiome that is less diverse and stable. Hence, the autoimmune microbiome for T1D may be distinctly different from that found in healthy children. These data also suggest bacterial markers for the early diagnosis of T1D. In addition, bacteria that negatively correlated with the autoimmune state may prove to be useful in the prevention of autoimmunity development in high-risk children. 相似文献
296.
Comment on: Rafn B, et al. Mol Cell 2012; 45:764-76. 相似文献
297.
The use of genetic modification (GM) in tree breeding would require that GM trees are superior to currently used seed orchard seedlings in the target trait and equal in other traits. We compare the variation of silver birch (Betula pendula Roth) lines carrying a sugar beet chitinase IV gene (chiIV) with the objective to improve fungal disease resistance to the variation of wild-type genotypes in disease resistance and other adaptive traits. The genetic variation in disease resistance was at the same level in transgenic (CVg 0.9?C19.0%) and wild-type trees (CVg 0?C19.7%), but the resistance characteristics of the most resistant wild-type genotype were usually equal or better than those of the best transgenic line. The broad-sense heritabilities varied from very low to moderate in disease resistance in both types. Broad-sense heritabilities in growth and leaf phenology-related traits were moderate and generally higher among the transgenic than the wild-type trees. The introduction of the sugar beet chiIV gene is likely to have fitness consequences in the form of lowered growth and quality characteristics of the transgenic lines without significant improvement in disease resistance compared with the natural variation of the same traits. 相似文献
298.
Tandem mass spectrometry-based proteomics experiments produce large amounts of raw data, and different database search engines are needed to reliably identify all the proteins from this data. Here, we present Compid, an easy-to-use software tool that can be used to integrate and compare protein identification results from two search engines, Mascot and Paragon. Additionally, Compid enables extraction of information from large Mascot result files that cannot be opened via the Web interface and calculation of general statistical information about peptide and protein identifications in a data set. To demonstrate the usefulness of this tool, we used Compid to compare Mascot and Paragon database search results for mitochondrial proteome sample of human keratinocytes. The reports generated by Compid can be exported and opened as Excel documents or as text files using configurable delimiters, allowing the analysis and further processing of Compid output with a multitude of programs. Compid is freely available and can be downloaded from http://users.utu.fi/lanatr/compid. It is released under an open source license (GPL), enabling modification of the source code. Its modular architecture allows for creation of supplementary software components e.g. to enable support for additional input formats and report categories. 相似文献
299.
300.
Evelyn N. Kouwenhoven Simon J. van Heeringen Juan J. Tena Martin Oti Bas E. Dutilh M. Eva Alonso Elisa de la Calle-Mustienes Leonie Smeenk Tuula Rinne Lilian Parsaulian Emine Bolat Rasa Jurgelenaite Martijn A. Huynen Alexander Hoischen Joris A. Veltman Han G. Brunner Tony Roscioli Emily Oates Meredith Wilson Miguel Manzanares José Luis Gómez-Skarmeta Hendrik G. Stunnenberg Marion Lohrum Hans van Bokhoven Huiqing Zhou 《PLoS genetics》2010,6(8)
Heterozygous mutations in p63 are associated with split hand/foot malformations (SHFM), orofacial clefting, and ectodermal abnormalities. Elucidation of the p63 gene network that includes target genes and regulatory elements may reveal new genes for other malformation disorders. We performed genome-wide DNA–binding profiling by chromatin immunoprecipitation (ChIP), followed by deep sequencing (ChIP–seq) in primary human keratinocytes, and identified potential target genes and regulatory elements controlled by p63. We show that p63 binds to an enhancer element in the SHFM1 locus on chromosome 7q and that this element controls expression of DLX6 and possibly DLX5, both of which are important for limb development. A unique micro-deletion including this enhancer element, but not the DLX5/DLX6 genes, was identified in a patient with SHFM. Our study strongly indicates disruption of a non-coding cis-regulatory element located more than 250 kb from the DLX5/DLX6 genes as a novel disease mechanism in SHFM1. These data provide a proof-of-concept that the catalogue of p63 binding sites identified in this study may be of relevance to the studies of SHFM and other congenital malformations that resemble the p63-associated phenotypes. 相似文献