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991.
Recent evidence supports a role of Toll-like receptor (TLR) signaling in the development of atherosclerotic lesions. It was
confirmed that the presence of functional TLR4 promotes a proinflammatory phenotype and proliferation of vascular smooth muscle
cells (VSMCs). Here we tested whether designed TLR4 small interfering RNAs (TLR4 siRNAs) is capable of inducing TLR4 deficient
and simultaneously regulating the expression of matrix metalloproteinase-9 (MMP-9) in human aortic smooth muscle cells (HASMCs).
Human aortic smooth muscle cells were obtained from Cascade Biologics (Portland, USA). The siRNAs used in this study were
chemically synthesized by Ambion, diluted in RNase free water at concentration of 2 μg/ml. The TLR4 siRNAs were complexed
with LipofectamineTM2000 in transfection buffer. After 30 min incubation at room temperature, the complexes were added to the cells. Subsequent
to 5 h incubation, cells were treated with 10 ng/ml LPS for 24 h. RT–PCR analysis was used to detect mRNA expression of GAPDH,
TLR4 and MMP-9; Western blot analysis was used to examine GAPDH, TLR4 and MMP-9 protein expression. It was shown that all
three designed TLR4 siRNAs inhibited the expression of TLR4 in HASMCs as compared to nontargeting siRNA. Notably, TLR4 siRNA-1
exhibited the strongest inhibition effect. Transfection of HASMCs with TLR4 siRNA-1 resulted in down-regulation of LPS-induced
expression of MMP-9. It was concluded that TLR4 siRNA-transfected HASMCs were capable for regulating the expression of MMP-9,
providing support for the rational design of siRNAs as atherosclerotic therapy. 相似文献
992.
993.
Anyuan He Yongju Luo Hong Yang Liping Liu Sifa Li Chenghui Wang 《Molecular biology reports》2011,38(3):2015-2021
Cichlid fishes have played an important role in evolutionary biology and aquaculture industry. Nile tilapia (Oreochromis niloticus), blue tilapia (Oreochromis aureus) and Mozambique tilapia (Oreochromis mossambicus), the useful models in studying evolutionary biology within Cichlid fishes, are also mainly cultured species in aquaculture
with great economic importance. In this paper, the complete nucleotide sequence of the mitochondrial genome for O. niloticus and O. aureus were determined and phylogenetic analyses from mitochondrial protein-coding genes were conducted to explore their phylogenetic
relationship within Cichlids. The mitogenome is 16,625 bp for O. niloticus and 16,628 bp for O. aureus, containing the same gene order and an identical number of genes or regions with the other Cichlid fishes, including 13 protein-coding
genes, two rRNA genes, 22 tRNA genes and one putative control region. Phylogenetic analyses using three different computational
algorithms (maximum parsimony, maximum likelihood and Bayesian method) show O. niloticus and O. mossambicus are closely related, and O. aureus has remotely phylogenetic relationship from above two fishes. 相似文献
994.
995.
996.
997.
Zeying Wang Genlin Wang Jingmin Huang Qiuling Li Changfa Wang Jifeng Zhong 《Molecular biology reports》2011,38(3):1749-1755
Genetic association analysis was applied to examine the effect of the Na+/K+-ATPase beta 2 subunit (ATP1B2) gene on rectal temperature, milk traits, K+ levels and Na+/K+-ATPase (NKA) activity in the red blood cells of 1001 Chinese Holstein cows under normal and heat-stress conditions. We detected
two novel single nucleotide polymorphisms, G2258A and C2833T, in the second and fourth introns, respectively, of ATP1B2. G2258A significantly affected milk fat content (P < 0.05) and 305-day milk yield (P < 0.01), but not milk protein content. C2833T significantly affected milk protein content (P < 0.01) and 305-day milk yield (P < 0.05), but not milk fat content. Calculated gene substitution effects suggested that A to G substitution in G2258A, and
T to C substitution in C2833T, positively affected milk fat content, 305-day milk yield and somatic cell score, but negatively
affected milk protein content. We also detected significant variation in milk fat content, milk protein content, 305-day milk
yield and somatic cell scores (P < 0.05 or P < 0.01) among the nine ATP1B2 haplotypes. Under heat-stress, the C2833T polymorphism was significantly related to rectal temperature (P < 0.01), red blood cell K+ levels, NKA activity and milk yield (P < 0.05). Cows with the TT genotype showed the desirable characteristics of low rectal temperature and red blood cell K+, low decline rate in milk yield and red blood cell NKA activity. This study suggests that the ATP1B2 single nucleotide polymorphism C2833T is a genetic marker of heat-resistance traits in Chinese Holstein cows. 相似文献
998.
Roberta Davoli Greta Gandolfi Silvia Braglia Marco Comella Paolo Zambonelli Luca Buttazzoni Vincenzo Russo 《Molecular biology reports》2011,38(3):1575-1583
PLIN2 (perilipin 2) is a cytosolic protein that promotes the formation and stabilization of the intracellular lipid droplets,
organelles involved in the storage of lipid depots. Porcine PLIN2 gene represents a biological and positional candidate for fat deposition, a polygenic trait that affects carcass and meat
quality. The aim of the present study was to screen PLIN2 gene for polymorphisms, to evaluate the association with carcass quality traits, and to investigate the gene expression in
skeletal muscle. Six new single nucleotide polymorphisms (SNP) were detected by sequencing 32 samples from five pig breeds
(Italian Large White, Italian Duroc, Italian Landrace, Belgian Landrace, Pietrain). Two SNP localized in introns, two in the
3′-untranslated region (UTR), and two missense SNP were found in exons. A 3′-UTR mutation (GU461317:g.98G>A), genotyped in
290 Italian Duroc pigs by High Resolution Melting, resulted significantly associated (P < 0.01) with average daily gain, feed conversion ratio, lean cuts and hams weight estimated breeding values. PLIN2 gene expression analysis in skeletal muscle of Italian Large White and Italian Duroc pigs divergent for backfat thickness
and visible intermuscular fat showed a trend of higher expression level in pigs with higher intermuscular fat. These results
suggest that PLIN2 can be a marker for carcass quality in pigs. Further investigation at both gene and protein level could elucidate its role
on fat deposition. 相似文献
999.
Xiaojun Lu Xingbo Song Yuanxin Ye Xianzhong Liu Yi Zhou Lei Zhang Jun Wang Binwu Ying Lanlan Wang 《Molecular biology reports》2011,38(5):3101-3105
The BCR–ABL fusion gene in chromosome translocation, t (9; 22), and its product, p210BCR/ABL oncogenic tyrosine kinase, is
the underlying molecular mechanism that leads to the development of CML. Quantitative detection of BCR–ABL fusion gene has
become a reliable approach to diagnose and monitor CML. The aim of this study was to evaluate a Roche t (9; 22) kit in CML
diagnosis, monitoring treatment responses, and identification of relapse. Using BCR–ABL fusion gene-expressing K562 cells,
a series of standard samples were prepared and used to establish a curve for the calculation of BCR–ABL fusion gene expression
in patient samples. Our results indicate that PCR detection system with aforementioned kit has good reproducibility. In addition,
the relative concentration of BCR–ABL measured by PCR was in agreement with the patient’s response to the Imatinib treatment
and bone marrow morphology remission. Furthermore, we found that the relative concentration of BCR–ABL fusion gene increased
1–3 months before CML relapse was clinically and cytogenetically diagnosed, suggesting that the PCR-based BCR–ABL fusion gene
detection with t (9; 22) kit is able to diagnose the recurrence of CML at least 1 month earlier than the classic cytogenetic
analysis. In conclusion, detection of BCR–ABL fusion gene expression in CML using Roche t (9; 22) kit has great clinical value
in the primary diagnosis, monitoring treatment responses, and identification of relapse in CML patients. 相似文献
1000.
The current treatment strategies, chemotherapy and radiation therapy being used for the management of cancer are deficient
in targeted approach leading to treatment related toxicities and relapse. Contrarily, fusion toxins exhibit remarkable tumor
specificity thus emerging as an alternative therapy for the treatment of cancer. Diphtheria toxin-HN-1 peptide (DT/HN-1) is
a fusion toxin designed to target the head and neck squamous cell carcinoma (HNSCC). The aim of this study was to construct,
characterize, and evaluate the cytotoxicity and specificity of DT/HN-1 fusion toxin against the HNSCC cells. The purified
DT/HN-1 fusion toxin was characterized by SDS-PAGE and western blotting. Refolding of purified fusion toxins was monitored
by fluorescence spectra and circular dichroism spectra. The activity of DT/HN-1 fusion toxin was demonstrated on various HNSCC
cell lines by cell viability assay, cell proliferation assay, protein synthesis inhibition assay, apoptosis and cell cycle
analysis. The fusion toxin DT/HN-1 demonstrated remarkably high degree of cytotoxicity specific to the HNSCC cells. The IC50 of DT/HN-1 fusion toxin was ~1 to 5 nM in all the three HNSCC cell lines. The percentage apoptotic cells in DT/HN-1 treated
UMB-SCC-745 cells are 16% compared to 4% in untreated. To further demonstrate the specific toxicity of DT/HN-1 fusion toxin
towards the HNSCC cells we constructed, characterized and evaluated the efficacy of DT protein. The DT protein coding for
only a fragment of diphtheria toxin without its native receptor binding domain failed to exhibit any cytotoxicity on all the
cell lines used in this study thus establishing the importance of a ligand in achieving targeted toxicity. To evaluate the
translocation ability of HN-1 peptide, an additional construct DTΔT/HN-1 was constructed, characterized and evaluated for
its cytotoxic activity. The fusion toxin DTΔT/HN-1 deficient of the translocation domain of diphtheria toxin showed no cytotoxicity
on all the cell lines clearly indicating the inability of HN-1 peptide to translocate catalytic domain of the toxin into the
cytosol. 相似文献