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DNA barcoding is based on the use of short DNA sequences to provide taxonomic tags for rapid, efficient identification of biological specimens. Currently, reference databases are being compiled. In the future, it will be important to facilitate access to these databases, especially for nonspecialist users. The method described here provides a rapid, web-based, user-friendly link between the DNA sequence from an unidentified biological specimen and various types of biological information, including the species name. Specifically, we use a customized, Google-type search algorithm to quickly match an unknown DNA sequence to a list of verified DNA barcodes in the reference database. In addition to retrieving the species name, our web tool also provides automatic links to a range of other information about that species. As the DNA barcode database becomes more populated, it will become increasingly important for the broader user community to be able to exploit it for the rapid identification of unknown specimens and to easily obtain relevant biological information about these species. The application presented here meets that need. 相似文献
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Shokralla S Zhou X Janzen DH Hallwachs W Landry JF Jacobus LM Hajibabaei M 《PloS one》2011,6(7):e21252
DNA barcoding is an effective approach for species identification and for discovery of new and/or cryptic species. Sanger sequencing technology is the method of choice for obtaining standard 650 bp cytochrome c oxidase subunit I (COI) barcodes. However, DNA degradation/fragmentation makes it difficult to obtain a full-length barcode from old specimens. Mini-barcodes of 130 bp from the standard barcode region have been shown to be effective for accurate identification in many animal groups and may be readily obtained from museum samples. Here we demonstrate the application of an alternative sequencing technology, the four-enzymes single-specimen pyrosequencing, in rapid, cost-effective mini-barcode analysis. We were able to generate sequences of up to 100 bp from mini-barcode fragments of COI in 135 fresh and 50 old Lepidoptera specimens (ranging from 53-97 year-old). The sequences obtained using pyrosequencing were of high quality and we were able to robustly match all the tested pyro-sequenced samples to their respective Sanger-sequenced standard barcode sequences, where available. Simplicity of the protocol and instrumentation coupled with higher speed and lower cost per sequence than Sanger sequencing makes this approach potentially useful in efforts to link standard barcode sequences from unidentified specimens to known museum specimens with only short DNA fragments. 相似文献
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Masoumeh Safari Faezeh Ghanati Mehrdad Behmanesh Abazar Hajnorouzi Bahareh Nahidian Ghahremani Mina 《Acta Physiologiae Plantarum》2013,35(9):2847-2855
Induction of antioxidant systems of hazel cells by low-energy ultrasound, the potential role of hydrogen peroxide (H2O2) as a signaling molecule in regulation of activity of stress-related enzymes, and expression of catalase (CAT) and phenylalanine ammonialyase (PAL) genes were investigated. Suspension-cultured Corylus avellana L. cells were agitated by an ultrasonic device at 29 kHz with the power of 4 mW/cm2, for 8–40 min. The activities of CAT, superoxide dismutase (SOD), and ascorbate peroxidase (APX) of treated cells increased by 4, 1.7 and 7 times of the control ones, respectively. Induction of increase in the expression of CAT gene started 24 h after the treatment with ultrasound. Significant increase also was observed in the expression of PAL gene, 6 h after exposure to ultrasound, which resulted in turn to increase of total contents of soluble phenolics, 24 h of the treatment. Exposure to ultrasound up to 20 min had no adverse effects on cell viability although it slightly increased the accumulation of H2O2. However, it is likely that this level of increased H2O2 was not deteriorative for hazel cells, but rather triggered antioxidant system and provided hazel cells a sustainable growth after ultrasound treatment. 相似文献
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Neda DAEI-FARSHBAF Reza AFLATOONIAN Fatemeh-Sadat AMJADI Sara TALEAHMAD Mahnaz ASHRAFI Mehrdad BAKHTIYARI 《Turkish Journal of Biology》2020,44(6):371
Odorant or olfactory receptors are mainly localized in the olfactory epithelium for the perception of different odors. Interestingly, many ectopic olfactory receptors with low expression levels have recently been found in nonolfactory tissues to involve in local functions. Therefore, we investigated the probable role of the olfactory signaling pathway in the surrounding microenvironment of oocyte. This study included 22 women in intracytoplasmic sperm injection cycle. The expression of olfactory target molecules in cumulus cells surrounding the growing and mature oocytes was evaluated by Western blotting and real-time polymerase chain reaction. Additionally, integrated bioinformatics analyses were carried out and 6 ectopic olfactory receptors were selected for further evaluation. The initiation of olfactory transduction cascade in cumulus cells of competent oocytes was confirmed by analyzing the expression of adenylyl cyclase type 3 and olfactory market protein. Moreover, the expression pattern of the selected olfactory receptors was evaluated and OR10H2 was selected due to a high level of expression in mature fertile oocytes. We suggested that OR10H2 could be considered as a reliable biomarker for oocyte selection in assisted reproduction technique programs. However, further studies are required to elucidate the role of olfactory transduction cascade in embryo quality and implantation. 相似文献
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Mohadeseh Haji Abdolvahab Hanka Venselaar Ahmad Fazeli S. Shahriar Arab Mehrdad Behmanesh 《International journal of peptide research and therapeutics》2020,26(3):1353-1361
Interferon beta (IFNβ) is naturally occurring cytokine made and secreted by immune cells in response to stimuli. Non-glycosylated interferon beta Ser 相似文献
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Zeinivand Motahareh Nahavandi Arezo Baluchnejadmojarad Tourandokht Roghani Mehrdad Golab Fereshteh 《International journal of peptide research and therapeutics》2020,26(2):1099-1106
International Journal of Peptide Research and Therapeutics - Hepcidin peptide is the dominant regulator of systemic iron metabolism. Studies suggest a dual role of hepcidin in neuronal iron load... 相似文献
110.
Simret Beraki Lily Litrus Liza Soriano Marie Monbureau Lillian K. To Steven P. Braithwaite Karoly Nikolich Roman Urfer Donna Oksenberg Mehrdad Shamloo 《PloS one》2013,8(7)
With the availability and ease of small molecule production and design continuing to improve, robust, high-throughput methods for screening are increasingly necessary to find pharmacologically relevant compounds amongst the masses of potential candidates. Here, we demonstrate that a primary oxygen glucose deprivation assay in primary cortical neurons followed by secondary assays (i.e. post-treatment protocol in organotypic hippocampal slice cultures and cortical neurons) can be used as a robust screen to identify neuroprotective compounds with potential therapeutic efficacy. In our screen about 50% of the compounds in a library of pharmacologically active compounds displayed some degree of neuroprotective activity if tested in a pre-treatment toxicity assay but just a few of these compounds, including Carbenoxolone, remained active when tested in a post-treatment protocol. When further examined, Carbenoxolone also led to a significant reduction in infarction size and neuronal damage in the ischemic penumbra when administered six hours post middle cerebral artery occlusion in rats. Pharmacological testing of Carbenoxolone-related compounds, acting by inhibition of 11-β-hydroxysteroid dehydrogenase-1 (11β-HSD1), gave rise to similarly potent in vivo neuroprotection. This indicates that the increase of intracellular glucocorticoid levels mediated by 11β-HSD1 may be involved in the mechanism that exacerbates ischemic neuronal cell death, and inhibiting this enzyme could have potential therapeutic value for neuroprotective therapies in ischemic stroke and other neurodegenerative disorders associated with neuronal injury. 相似文献