Construction and sequence analysis of a normalized full-length cDNA library of Dendrobium officinale / 中国中药杂志

<p><b>OBJECTIVE</b>In order to obtain functional genes, a normalized stems cDNA library was constructed from medicinal plant Dendrobium officinale.</p><p><b>METHOD</b>SMART (switching mechanism at 5' end of RNA transcript) cDNA synthesis combined with DSN (duplex-specific nuclease) normalization was applied to construct the normalized full-length cDNA library of D. officinale.</p><p><b>RESULT</b>The titer of cDNA library was about 1.3 x 10(6) cfu x mL(-1) and the average insertion size was about 1.5 kb with high recombination rate (93.9%). Random selected 163 positive clones were sequenced at single side. Bio-information analysis indicated that 147 from 150 high-quality unique sequences matched corresponding homologous proteins, and they participated in various biological processes based on GO (gene ontology). There were 8 clones with complete coding sequence, which presumed to be full-length genes.</p><p><b>CONCLUSION</b>These results showed preliminarily that we successfully constructed a normalized full-length cDNA library of D. officinale which could be used to screen the functional genes related to metabolic pathways of medicinal ingredients.</p>

Epidemiological investigation of Borna disease virus infection in horses and donkeys in Yili, Xinjiang / 中华微生物学和免疫学杂志

Objective To investigate the epidemiology of BDV infection in Yili horses and Yili donkeys and to analyze phylogenetic source of BDV in Yili area, Xinjiang. Methods We established fluo- rescence quantitative nested RT-PCR to detect BDV p24 segment in peripheral blood mononuclear cells (PBMCs) of 518 Yili horses and 206 Yili donkeys in Yili area, Xinjiang. Positive products were validated by detecting BDV p40 segment and plasmid to preclude the contamination, and were sequenced to analyze the homology of gene sequence, amino acid sequence and phylogenetic tree. Results The positive rates of BDV infection in PBMCs of 518 Yili horses and 206 Yili donkeys were 0.97% and 1.94%, respectively. The results of BDV p40 segment verification were positive in all of the samples of BDV p24 positive. All the samples tested were not contaminated by plasmid. There was a homology of the gene sequence of positive PCR samples with strain He/80. And the gene sequence revealed more than 93% identical to H1766 and strain V. Conclusion Our study suggested BDV natural infection in Yili horses and Yili donkeys. The en- demic BDV had a high degree of identity to strain He/80.

The advantages for Snail expression to promote cell migration and induce actin reorganization and to protect against the serum-deprivation-triggered apoptosis of bone marrow stem cells / 生物工程学报

The Snail transcription factor has been described as a strong repressor of E-cadherin and its stable expression induces epithelial-mesenchymal transitions responsible for the acquisition of motile and invasive properties during tumor progression. A fascinating analogy that has been raised is the seemingly similar and shared characteristics of stem cells and tumorigenic cells, which prompted us to investigate whether the mechanisms of the acquisition of invasiveness during tumor progression are also involved in bone marrow stem cells (MSCs). In this study, we examined whether Snail gene expression acts in the mobility, cytoskeleton and anti-apoptosis of MSCs. Cell Transmigration Assay and Western Blotting were performed to evaluate the cell migratory capability and the related Signaling pathways in MSCs transfected with the Snail expression vector of pCAGGSneo-SnailHA (MSCs-Sna), compared with MSCs(MSCs-neo) transducted with the control vector(pCAGGSneo). Actin cytoskeleton by Immunofluorescence and Sub-G1 detection by a FACScan flow cytometer were performed to analyze the cytoskeleton and antiapoptotic capability of MSCs-Sna. Compared with MSCs-neo, MSCs-Sna show significantly more migration in the transwell migration system (P < 0.05). And suppression of PI-3K activation by the specific PI-3K inhibitor, Wortmannin, brought on a reduction in Snail-mediated MSCs migration. In addition, we provide evidences that high expression of Snail inhibited the serum-deprivation triggered apoptosis and cytoskeleton changement of MSCs. These data suggest the possibility of facilitating MSCs migration to injured tissue and subsequent survival and maintenance in the local microenvironment after their transplantation, by investigating and increasing the advantage factors such as Snail high expression in MSCs.