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1.  Identification and Characterization of Long Non-Coding RNAs Related to Mouse Embryonic Brain Development from Available Transcriptomic Data 
PLoS ONE  2013;8(8):e71152.
Long non-coding RNAs (lncRNAs) as a key group of non-coding RNAs have gained widely attention. Though lncRNAs have been functionally annotated and systematic explored in higher mammals, few are under systematical identification and annotation. Owing to the expression specificity, known lncRNAs expressed in embryonic brain tissues remain still limited. Considering a large number of lncRNAs are only transcribed in brain tissues, studies of lncRNAs in developmental brain are therefore of special interest. Here, publicly available RNA-sequencing (RNA-seq) data in embryonic brain are integrated to identify thousands of embryonic brain lncRNAs by a customized pipeline. A significant proportion of novel transcripts have not been annotated by available genomic resources. The putative embryonic brain lncRNAs are shorter in length, less spliced and show less conservation than known genes. The expression of putative lncRNAs is in one tenth on average of known coding genes, while comparable with known lncRNAs. From chromatin data, putative embryonic brain lncRNAs are associated with active chromatin marks, comparable with known lncRNAs. Embryonic brain expressed lncRNAs are also indicated to have expression though not evident in adult brain. Gene Ontology analysis of putative embryonic brain lncRNAs suggests that they are associated with brain development. The putative lncRNAs are shown to be related to possible cis-regulatory roles in imprinting even themselves are deemed to be imprinted lncRNAs. Re-analysis of one knockdown data suggests that four regulators are associated with lncRNAs. Taken together, the identification and systematic analysis of putative lncRNAs would provide novel insights into uncharacterized mouse non-coding regions and the relationships with mammalian embryonic brain development.
PMCID: PMC3743905  PMID: 23967161
2.  Toxicity Assessment of Cadinene Sesquiterpenes from Eupatorium adenophorum in Mice 
This study evaluated toxic efficacy of Eupatorium adenophorum extracts, against the Kunming mice. In acute study, we firstly tested median lethal dose (LD50) in mice of three cadinene sesquiterpenes 2-deoxo-2-(acetyloxy)-9-oxoageraphorone (DAOA), 9-oxo-agerophorone (OA) and 9-oxo-10,11-dehydro-agerophorone (ODA) from Eupatorium adenophorum (Ea). DAOA (215–4640 mg/kg BW, given orally) showed lowest LD50 at 926 mg/kg BW for male mice in contrast with OA (1470 mg/kg BW) and ODA (1470 mg/kg BW). In sub-acute study, repeated doses (75–300 mg/kg BW, for 7 days) of DAOA/OA increased blood parameters, liver and spleen index in dose dependent relationship, along with decrease in thymus index. The blood biochemical and histopathological examination showed that DAOA/OA dose 300 mg/kg BW significantly causes pathological changes of hepatic lobules and hepatocytes, which are consistent with cholestasis and hepatic injury. 75 mg/kg dose of DAOA/OA was found to be approximately/totally safe over the span of 7 days treatment showing no change in all above described parameters. Cadinene sesquiterpenes guarantee low risk to environment as a type of low toxic botanical components, which may find potential application in biopesticides development field.
Graphical Abstract
PMCID: PMC4327999  PMID: 25500813
Eupatorium adenophorum; Sesquiterpenes; Histopathology; Environmental toxicity; Biopesticide
3.  Toxicity Assessment of Cadinene Sesquiterpenes from Eupatorium adenophorum in Mice 
This study evaluated toxic efficacy of Eupatorium adenophorum extracts, against the Kunming mice. In acute study, we firstly tested median lethal dose (LD50) in mice of three cadinene sesquiterpenes 2-deoxo-2-(acetyloxy)-9-oxoageraphorone (DAOA), 9-oxo-agerophorone (OA) and 9-oxo-10,11-dehydro-agerophorone (ODA) from Eupatorium adenophorum (Ea). DAOA (215–4640 mg/kg BW, given orally) showed lowest LD50 at 926 mg/kg BW for male mice in contrast with OA (1470 mg/kg BW) and ODA (1470 mg/kg BW). In sub-acute study, repeated doses (75–300 mg/kg BW, for 7 days) of DAOA/OA increased blood parameters, liver and spleen index in dose dependent relationship, along with decrease in thymus index. The blood biochemical and histopathological examination showed that DAOA/OA dose 300 mg/kg BW significantly causes pathological changes of hepatic lobules and hepatocytes, which are consistent with cholestasis and hepatic injury. 75 mg/kg dose of DAOA/OA was found to be approximately/totally safe over the span of 7 days treatment showing no change in all above described parameters. Cadinene sesquiterpenes guarantee low risk to environment as a type of low toxic botanical components, which may find potential application in biopesticides development field.
Graphical Abstract
PMCID: PMC4327999  PMID: 25500813
Eupatorium adenophorum; Sesquiterpenes; Histopathology; Environmental toxicity; Biopesticide
4.  The Evolutionary History and Spatiotemporal Dynamics of the Fever, Thrombocytopenia and Leukocytopenia Syndrome Virus (FTLSV) in China 
In 2007, a novel bunyavirus was found in Henan Province, China and named fever, thrombocytopenia and leukocytopenia syndrome virus (FTLSV); since then, FTLSV has been found in ticks and animals in many Chinese provinces. Human-to-human transmission has been documented, indicating that FTLSV should be considered a potential public health threat. Determining the historical spread of FTLSV could help curtail its spread and prevent future movement of this virus.
Method/Principal Findings
To examine the pattern of FTLSV evolution and the origin of outbreak strains, as well to examine the rate of evolution, the genome of 12 FTLSV strains were sequenced and a phylogenetic and Bayesian phylogeographic analysis of all available FTLSV sequences in China were performed. Analysis based on the FTLSV L segment suggests that the virus likely originated somewhere in Huaiyangshan circa 1790 (95% highest probability density interval: 1756–1817) and began spreading around 1806 (95% highest probability density interval: 1773–1834). Analysis also indicates that when FTLSV arrived in Jiangsu province from Huaiyangshan, Jiangsu Province became another source for the spread of the disease. Bayesian factor test analysis identified three major transmission routes: Huaiyangshan to Jiangsu, Jiangsu to Liaoning, and Jiangsu to Shandong. The speed of FTLSV movement has increased in recent decades, likely facilitated by modern human activity and ecosystem changes. In addition, evidence of RNA segment reassortment was found in FTLSV; purifying selection appears to have been the dominant force in the evolution of this virus.
Results presented in the manuscript suggest that the Huaiyangshan area is likely be the origin of FTLSV in China and identified probable viral migration routes. These results provide new insights into the origin and spread of FTLSV in China, and provide a foundation for future virological surveillance and control.
Author Summary
FTLSV is novel bunyavirus belonging to genus Phlebovirus and was first found in Huaiyangshan area. The epidemiology and pathogenesis of FTLSV remain poorly understood. This lack of information underscores the importance of analyzing the movement and genetic history of FTLSV in China. Recent advances in Bayesian coalescent phylogenetic analyses have resulted in more sophisticated methods being available for determining the relative age of emerging pathogens. In this study, a phylogenetic and Bayesian phylogeographic analysis was performed for FTLSV whole genomic sequences isolated from China. Results identified the Huaiyangshan area as the most probable origin of FTLSV and suggested migrating routes of the virus. These results offer the first description of the movement and history of FTLSV in China. RNA segment reassortment was found in FTLSV; purifying selection appears to have been the dominant force driving the evolution of this virus. The results of this study could be used to facilitate the development of new strategies for controlling FTLSV.
PMCID: PMC4199521  PMID: 25329580
5.  Self-control study of combination treatment of 308 nm excimer laser and calcipotriene ointment on stable psoriasis vulgaris 
Objective: This study aims to compare the differences of clinical efficacy and safety of treatment of stable psoriasis vulgaris with calcipotriene ointment in combination with 308 nm excimer laser to 308 nm excimer laser alone. Methods: Randomized, open and self-control trial was conducted in 36 selected patients. The skin lesions from these patients with stable psoriasis vulgaris were divided into two sides along the midline of torso, one side was treated with 308 nm excimer laser, 2 times/week, at meantime Calcipotriene was applied externally, 2 times/day (treatment group); the other side was given 308 nm excimer laser alone, 2 times/week, the treatment period was 6 weeks (control group). Skin lesion area, PASI scores and cumulative doses of 308 nm excimer laser in patients with psoriasis were assessed before treatment and on weeks 2, 4 and 6 after treatment. Results: 32 of 36 patients with stable psoriasis vulgaris completed study, effective rates in two groups were better on week 6 (84.37%, 56.25%) than on week 4 (53.12%, 37.5%) and on week 2 (31.25%, 18.75%) (P < 0.05). Effective rate on week 6 in control group (56.25%) was lower than treatment group (84.37%) (P < 0.05). The two groups showed that PASI scores on weeks 2 and 4 after treatment were significantly lower than before treatments (P < 0.05), and PASI scores on week 6 in treatment group was significantly lower than control group (P < 0.05). The average cumulative laser doses in treatment group at the end of trial was 4.69 (2.03) J/cm2, which was significantly lower than in control group 8.41 (2.42) J/cm (P < 0.05). Treatment efficacies in the head, folds, back, abdomen and limbs were similar and no serious adverse effects, however the number of treatment and irradiation doses in the head and folds were significantly less than in back, abdomen and limbs (P < 0.05). Conclusions: Treatment of psoriasis vulgaris with 308 nm excimer laser in combination with external application of Calcipotriene ointment can improve long-term treatment efficacy, decrease cumulative laser doses, and reduce adverse effects induced by laser irradiations.
PMCID: PMC4211797  PMID: 25356147
Psoriasis; vulgaris; excimer Laser; calcipotriene
6.  Characterization and Plasmid Elimination of NDM-1-Producing Acinetobacter calcoaceticus from China 
PLoS ONE  2014;9(9):e106555.
The presence of multidrug-resistant bacterial pathogens in the environment poses a serious threat to public health. The opportunistic Acinetobacter spp. are among the most prevalent causes of nosocomial infections. Here, we performed complete genome sequencing of the Acinetobacter calcoaceticus strain XM1570, which was originally cultivated from the sputum of a patient diagnosed with pneumonia in Xiamen in 2010. We identified carbapenem resistance associated gene blaNDM-1 located on a 47.3-kb plasmid. Three methods – natural reproduction, sodium dodecyl sulfate treatment and nalidixic acid treatment – were used to eliminate the blaNDM-1-encoding plasmid, which achieved elimination rates of 3.32% (10/301), 83.78% (278/332), and 84.17% (298/354), respectively. Plasmid elimination dramatically increased antibiotic sensitivity, reducing the minimum bacteriostatic concentration of meropenem from 256 µg/ml in the clinical strain to 0.125 µg/ml in the plasmid-eliminated strain. Conjugation transfer assays showed that the blaNDM-1-containing plasmid could be transferred into Escherichia coli DH5α:pBR322 in vitro as well as in vivo in mice. The blaNDM-1 genetic environment was in accordance with that of other blaNDM-1 genes identified from India, Japan, and Hong-Kong. The multilocus sequence type of the isolate was identified as ST-70. Two novel genes encoding intrinsic OXA and ADC were identified and named as OXA-417 and ADC-72. The finding of blaNDM-1 in species like A. calcoaceticus demonstrates the wide spread of this gene in gram-negative bacteria which is possible by conjugative plasmid transfer. The results of this study may help in the development of a treatment strategy for controlling NDM-1 bacterial infection and transmission.
PMCID: PMC4152304  PMID: 25181293
7.  Primary desmoplastic small round cell tumor of the duodenum 
The desmoplastic small round cell tumor (DSRCT) is an extremely rare tumor that mainly affects adolescents and mostly involves the abdominal and pelvic peritoneum. A 14-year-old girl presented with intermittent epigastric pain; abdominal computed tomography and upper gastrointestinal barium X-ray revealed an 8 cm × 10 cm space-occupying mass in the duodenal region. The patient underwent pancreaticoduodenectomy and the final pathologic diagnosis was DSRCT. Although multi-agent systemic chemotherapy was given, the patient died of metastasis 8 months later. Early diagnosis and surgical treatment with adjuvant chemotherapy seems to be the best treatment choice for this disease.
PMCID: PMC4096735  PMID: 24997683
chemotherapy; desmoplastic small round cell tumor; duodenum; surgery
8.  Nucleolus-tethering system (NoTS) reveals that assembly of photobodies follows a self-organization model 
Molecular Biology of the Cell  2014;25(8):1366-1373.
A nucleolus-tethering system (NoTS) based on nucleolin2 is developed by artificially tethering a protein of interest to the nucleolus for analyzing protein–protein interactions and the initiation of nuclear bodies. The NoTS is used to demonstrate a self-organization model for the biogenesis of photobodies.
Protein–protein interactions play essential roles in regulating many biological processes. At the cellular level, many proteins form nuclear foci known as nuclear bodies in which many components interact with each other. Photobodies are nuclear bodies containing proteins for light-signaling pathways in plants. What initiates the formation of photobodies is poorly understood. Here we develop a nucleolar marker protein nucleolin2 (Nuc2)–based method called the nucleolus-tethering system (NoTS) by artificially tethering a protein of interest to the nucleolus to analyze the initiation of photobodies. A candidate initiator is evaluated by visualizing whether a protein fused with Nuc2 forms body-like structures at the periphery of the nucleolus, and other components are recruited to the de novo–formed bodies. The interaction between two proteins can also be revealed through relocation and recruitment of interacting proteins to the nucleolus. Using the NoTS, we test the interactions among components in photobodies. In addition, we demonstrate that components of photobodies such as CONSTITUTIVELY PHOTOMORPHOGENIC 1, photoreceptors, and transcription factors tethered to the nucleolus have the capacity to form body-like structures at the periphery of the nucleolus, which contain other components of photobodies, suggesting a self-organization model for the biogenesis of photobodies.
PMCID: PMC3983000  PMID: 24554768
9.  A Novel Multi-Unit Tablet for Treating Circadian Rhythm Diseases 
AAPS PharmSciTech  2013;14(2):861-869.
This study aimed to develop and evaluate a novel multi-unit tablet that combined a pellet with a sustained-release coating and a tablet with a pulsatile coating for the treatment of circadian rhythm diseases. The model drug, isosorbide-5-mononitrate, was sprayed on microcrystalline cellulose (MCC)-based pellets and coated with Eudragit® NE30D, which served as a sustained-release layer. The coated pellets were compressed with cushion agents (a mixture of MCC PH-200/ MCC KG-802/PC-10 at a ratio of 40:40:20) at a ratio of 4:6 using a single-punch tablet machine. An isolation layer of OpadryII, swellable layer of HPMC E5, and rupturable layer of Surelease® were applied using a conventional pan-coating process. Central-composite design-response surface methodology was used to investigate the influence of these coatings on the square of the difference between release times over a 4 h time period. Drug release studies were carried out on formulated pellets and tablets to investigate the release behaviors, and scanning electron microscopy (SEM) was used to monitor the pellets and tablets and their cross-sectional morphology. The experimental results indicated that this system had a pulsatile dissolution profile that included a lag period of 4 h and a sustained-release time of 4 h. Compared to currently marketed preparations, this tablet may provide better treatment options for circadian rhythm diseases.
PMCID: PMC3666023  PMID: 23649996
central composite design; circadian rhythm diseases; in vitro dissolution study; multi-unit tablet; sustained-release and pulsatile coating
10.  Injury to the Endothelial Surface Layer Induces Glomerular Hyperfiltration Rats with Early-Stage Diabetes 
Journal of Diabetes Research  2014;2014:953740.
Glomerular endothelial surface layer (ESL) may play a role in the mechanisms of albuminuria in diabetic nephropathy, which lack evidence in vivo. The effects of high glucose on the passage of albumin across the glomerular ESL were analysed in streptozotocin-induced diabetic Sprague-Dawley rats for 4 weeks. Albuminuria and glomerular mesangial matrix were significantly increased in diabetic rats. The passage of albumin across the ESL, as measured by albumin-colloid gold particle density in the glomerular basement membrane (GBM), was increased significantly in diabetic rats. The thickness of the glomerular ESL, examined indirectly by infusing Intralipid into vessels using an electron microscope, was significantly decreased and the GBM exhibited little change in diabetic rats. In summary, the glomerular ESL may play a role in the pathogenesis of albuminuria in rats with early-stage diabetes.
PMCID: PMC4000657  PMID: 24812636
11.  Cyclin G2 Suppresses Estrogen-Mediated Osteogenesis through Inhibition of Wnt/β-Catenin Signaling 
PLoS ONE  2014;9(3):e89884.
Estrogen plays an important role in the maintenance of bone formation, and deficiency in the production of estrogen is directly linked to postmenopausal osteoporosis. To date, the underlying mechanisms of estrogen-mediated osteogenic differentiation are not well understood. In this study, a pluripotent mesenchymal precursor cell line C2C12 was used to induce osteogenic differentiation and subjected to detection of gene expressions or to manipulation of cyclin G2 expressions. C57BL/6 mice were used to generate bilateral ovariectomized and sham-operated mice for analysis of bone mineral density and protein expression. We identified cyclin G2, an unconventional member of cyclin, is involved in osteoblast differentiation regulated by estrogen in vivo and in vitro. In addition, the data showed that ectopic expression of cyclin G2 suppressed expression of osteoblast transcription factor Runx2 and osteogenic differentiation marker genes, as well as ALP activity and in vitro extracellular matrix mineralization. Mechanistically, Wnt/β-catenin signaling pathway is essential for cyclin G2 to inhibit osteogenic differentiation. To the best of our knowledge, the current study presents the first evidence that cyclin G2 serves as a negative regulator of both osteogenesis and Wnt/β-catenin signaling. Most importantly, the basal and 17β-estradiol-induced osteogenic differentiation was restored by overexpression of cyclin G2. These results taken together suggest that cyclin G2 may function as an endogenous suppressor of estrogen-induced osteogenic differentiation through inhibition of Wnt/β-catenin signaling.
PMCID: PMC3940656  PMID: 24595300
12.  Longitudinal Variability of Phosphorus Fractions in Sediments of a Canyon Reservoir Due to Cascade Dam Construction: A Case Study in Lancang River, China 
PLoS ONE  2013;8(12):e83329.
Dam construction causes the accumulation of phosphorus in the sediments of reservoirs and increases the release rate of internal phosphorus (P) loading. This study investigated the longitudinal variability of phosphorus fractions in sediments and the relationship between the contents of phosphorus fractions and its influencing factors of the Manwan Reservoir, Lancang River, Yunnan Province, China. Five sedimentary phosphorus fractions were quantified separately: loosely bound P (ex-P); reductant soluble P (BD-P); metal oxide-bound P (NaOH-P); calcium-bound P (HCl-P), and residual-P. The results showed that the total phosphorus contents ranged from 623 to 899 µg/g and were correlated positively with iron content in the sediments of the reservoir. The rank order of P fractions in sediments of the mainstream was HCl-P>NaOH-P>residual-P>BD-P>ex-P, while it was residual-P>HCl-P>NaOH-P>BD-P>ex-P in those of the tributaries. The contents of bio-available phosphorus in the tributaries, including ex-P, BD-P and NaOH-P, were significantly lower than those in the mainstream. The contents of ex-P, BD-P, NaOH-P showed a similar increasing trend from the tail to the head of the Manwan Reservoir, which contributed to the relatively higher content of bio-available phosphorus, and represents a high bio-available phosphorus releasing risk within a distance of 10 km from Manwan Dam. Correlation and redundancy analyses showed that distance to Manwan Dam and the silt/clay fraction of sediments were related closely to the spatial variation of bio-available phosphorus.
PMCID: PMC3873304  PMID: 24386180
13.  Type I J-Domain NbMIP1 Proteins Are Required for Both Tobacco Mosaic Virus Infection and Plant Innate Immunity 
PLoS Pathogens  2013;9(10):e1003659.
Tm-22 is a coiled coil-nucleotide binding-leucine rich repeat resistance protein that confers durable extreme resistance against Tomato mosaic virus (ToMV) and Tobacco mosaic virus (TMV) by recognizing the viral movement protein (MP). Here we report that the Nicotiana benthamiana J-domain MIP1 proteins (NbMIP1s) associate with tobamovirus MP, Tm-22 and SGT1. Silencing of NbMIP1s reduced TMV movement and compromised Tm-22-mediated resistance against TMV and ToMV. Furthermore, silencing of NbMIP1s reduced the steady-state protein levels of ToMV MP and Tm-22. Moreover, NbMIP1s are required for plant resistance induced by other R genes and the nonhost pathogen Pseudomonas syringae pv. tomato (Pst) DC3000. In addition, we found that SGT1 associates with Tm-22 and is required for Tm-22-mediated resistance against TMV. These results suggest that NbMIP1s function as co-chaperones during virus infection and plant immunity.
Author Summary
Plant pathogens cause considerable yield losses in many vegetables and crops; therefore, understanding the mechanisms of disease resistance can enable crop improvements and provide substantial economic benefits. Here, we examine the signaling pathways of Tm-22, a tomato resistance protein that confers resistance to Tomato mosaic virus (ToMV) and Tobacco mosaic virus (TMV) by detecting the presence of their movement proteins (MPs). We found that in Nicotiana benthamiana, Tm-22-mediated resistance against TMV and ToMV requires MIP1s (NbMIP1s), a group of J-domain proteins that may act as molecular chaperones to assist protein folding and maintain protein structure. Intriguingly, MIP1s are required for both TMV resistance and TMV infection. NbMIP1s interact with and are essential for protein stability of both Tm-22 and the viral MP. NbMIP1s are required for resistance mediated by other resistance proteins and resistance to the bacterial nonhost pathogen Pseudomonas syringae pv. tomato (Pst) DC3000. These new insights into the mechanisms of viral infection and disease resistance may enable future advances in crop protection.
PMCID: PMC3789785  PMID: 24098120
14.  CBrowse: a SAM/BAM-based contig browser for transcriptome assembly visualization and analysis 
Bioinformatics  2012;28(18):2382-2384.
Summary: To address the impending need for exploring rapidly increased transcriptomics data generated for non-model organisms, we developed CBrowse, an AJAX-based web browser for visualizing and analyzing transcriptome assemblies and contigs. Designed in a standard three-tier architecture with a data pre-processing pipeline, CBrowse is essentially a Rich Internet Application that offers many seamlessly integrated web interfaces and allows users to navigate, sort, filter, search and visualize data smoothly. The pre-processing pipeline takes the contig sequence file in FASTA format and its relevant SAM/BAM file as the input; detects putative polymorphisms, simple sequence repeats and sequencing errors in contigs and generates image, JSON and database-compatible CSV text files that are directly utilized by different web interfaces. CBowse is a generic visualization and analysis tool that facilitates close examination of assembly quality, genetic polymorphisms, sequence repeats and/or sequencing errors in transcriptome sequencing projects.
Availability: CBrowse is distributed under the GNU General Public License, available at
Contact: or;
Supplementary Information: Supplementary data are available at Bioinformatics online.
PMCID: PMC3436847  PMID: 22789590
15.  Recombinant Rat CC10 Protein Inhibits PDGF-Induced Airway Smooth Muscle Cells Proliferation and Migration 
BioMed Research International  2013;2013:690937.
Abnormal migration and proliferation of airway smooth muscle cells (ASMCs) in the airway cause airway wall thickening, which is strongly related with the development of airway remodeling in asthma. Clara cell 10 kDa protein (CC10), which is secreted by the epithelial clara cells of the pulmonary airways, plays an important role in the regulation of immunological and inflammatory processes. Previous studies suggested that CC10 protein had great protective effects against inflammation in asthma. However, the effects of CC10 protein on ASMCs migration and proliferation in airway remodeling were poorly understood. In this study, we constructed the pET-22b-CC10 recombinant plasmid, induced expression and purified the recombinant rat CC10 protein from E. coli by Ni2+ affinity chromatography and ion exchange chromatography purification. We investigated the effect of recombinant rat CC10 protein on platelet-derived growth factor (PDGF)-BB-induced ASMCs proliferation and migration. Our results demonstrated that the recombinant CC10 protein could inhibit PDGF-BB-induced cell viability, proliferation and migration. Western blot analysis showed that PDGF-BB-induced activation of cyclin D1 was inhibited by CC10. These findings implicated that CC10 could inhibit increased ASMCs proliferation, and migration induced by PDGF-BB, and this suppression effect might be associated with inhibition of cyclin D1 expression, which might offer hope for the future treatment of airway remodeling.
PMCID: PMC3784082  PMID: 24106713
16.  Protein phosphorylation-acetylation cascade connects growth factor deprivation to autophagy 
Autophagy  2012;8(9):1385-1386.
Different from unicellular organisms, metazoan cells require the presence of extracellular growth factors to utilize environmental nutrients. However, the underlying mechanism was unclear. We have delineated a pathway, in which glycogen synthase kinase 3 (GSK3) in cells deprived of growth factors phosphorylates and activates the acetyltransferase KAT5/TIP60, which in turn stimulates the protein kinase ULK1 to elicit autophagy. Cells with the Kat5/Tip60 gene replaced with Kat5S86A that cannot be phosphorylated by GSK3 are resistant to serum starvation-induced autophagy. Acetylation sites on ULK1 were mapped to K162 and K606, and the acetylation-defective mutant ULK1K162,606R displays reduced kinase activity and fails to rescue autophagy in Ulk1−/− mouse embryonic fibroblasts, indicating that acetylation is vital to the activation of ULK1. The GSK3-KAT5-ULK1 cascade seems to be specific for cells to sense growth factors, as KAT5 phosphorylation is not enhanced under glucose deprivation. Distinct from the glucose starvation-autophagy pathway that is conserved in all eukaryotic organisms, the growth factor deprivation response pathway is perhaps unique to metazoan organisms.
PMCID: PMC3442885  PMID: 22717509
GSK3; Tip60; Ulk1; acetylation; autophagy; growth factor; phosphorylation
17.  Engineered Endothelial Progenitor Cells That Overexpress Prostacyclin Protect Vascular Cells 
Journal of Cellular Physiology  2012;227(7):2907-2916.
Prostacyclin (PGI2) is a potent vasodilator and important mediator of vascular homeostasis; however, its clinical use is limited because of its short (<2 minute) half-life. Thus, we hypothesize that the use of engineered endothelial progenitor cells (EPCs) that constitutively secrete high levels of PGI2 may overcome this limitation of PGI2 therapy. A cDNA encoding COX-1-10aa-PGIS, which links human cyclooxygenase-1(COX-1) to prostacyclin synthase (PGIS), was delivered via nucleofection into outgrowth endothelial progenitor cells (EPCs) derived from rat bone marrow mononuclear cells. PGI2-secreting strains (PGI2-EPCs) were established by continuous subculturing of transfected cells under G418 selection. Genomic PCR, RT-PCR, and Western blot analyses confirmed the overexpression of COX-1-10aa-PGIS in PGI2-EPCs. PGI2-EPCs secreted significantly higher levels of PGI2 in vitro than native EPCs (P<0.05) and showed higher intrinsic angiogenic capability; conditioned medium from PGI2-EPCs promoted better tube formation than conditioned medium from native EPCs (P<0.05). Cell- and paracrine-mediated in vitro angiogenesis was attenuated when COX-1-10aa-PGIS protein expression was knocked down. Whole-cell patch-clamp studies showed that 4-aminopyridine–sensitive K+ current density was increased significantly in rat smooth muscle cells (rSMCs) cocultured under hypoxia with PGI2-EPCs (7.50±1.59pA/pF, P<0.05.) compared with rSMCs cocultured with native EPCs (3.99±1.26 pA/pF.). In conclusion, we successfully created EPC strains that overexpress an active novel enzyme resulting in consistent secretion of PGI2. PGI2-EPCs showed enhanced intrinsic proangiogenic properties and provided favorable paracrine-mediated cellular protections, including promoting in-vitro angiogenesis of native EPCs and hyperpolarization of SMCs under hypoxia.
PMCID: PMC3292628  PMID: 21938725
endothelial progenitor cells; prostacyclin; angiogenesis; paracrine; patch clamp
18.  Complete Genome Sequence of Dengue Virus Serotype 4 from Guangzhou, China 
Genome Announcements  2013;1(3):e00299-13.
In 2010, the first complete genome sequence of a dengue virus serotype 4 genotype II strain was reported in Guangzhou, China. Here, we report another isolated strain belonging to the genotype II. Our results will offer help to dengue virus control and precautions.
PMCID: PMC3668008  PMID: 23723400
19.  Complete Genome Sequence of Dengue Virus Serotype 3 from Guangzhou, China 
Genome Announcements  2013;1(2):e00208-12.
In 2009, dengue virus serotype 3 (DENV-3) was first detected in Guangzhou, China. In this study, we identified another isolated strain belonging to genotype II. Phylogenetic analysis shows that the GZ/10476/2012 strain has a close relationship with the DENV-3 genotype II from Southeast Asian strains.
PMCID: PMC3593333  PMID: 23516231
20.  Transcriptome Exploration in Leymus chinensis under Saline-Alkaline Treatment Using 454 Pyrosequencing 
PLoS ONE  2013;8(1):e53632.
Leymus chinensis (Trin.) Tzvel. is a high saline-alkaline tolerant forage grass genus of the tribe Gramineae family, which also plays an important role in protection of natural environment. To date, little is known about the saline-alkaline tolerance of L. chinensis on the molecular level. To better understand the molecular mechanism of saline-alkaline tolerance in L. chinensis, 454 pyrosequencing was used for the transcriptome study.
We used Roche-454 massive parallel pyrosequencing technology to sequence two different cDNA libraries that were built from the two samples of control and under saline-alkaline treatment (optimal stress concentration-Hoagland solution with 100 mM NaCl and 200 mM NaHCO3). A total of 363,734 reads in control group and 526,267 reads in treatment group with an average length of 489 bp and 493 bp were obtained, respectively. The reads were assembled into 104,105 unigenes with MIRA sequence assemable software, among which, 73,665 unigenes were in control group, 88,016 unigenes in treatment group and 57,576 unigenes in both groups. According to the comparative expression analysis between the two groups with the threshold of “log2 Ratio ≥1”, there were 36,497 up-regulated unegenes and 18,218 down-regulated unigenes predicted to be the differentially expressed genes. After gene annotation and pathway enrichment analysis, most of them were involved in stress and tolerant function, signal transduction, energy production and conversion, and inorganic ion transport. Furthermore, 16 of these differentially expressed genes were selected for real-time PCR validation, and they were successfully confirmed with the results of 454 pyrosequencing.
This work is the first time to study the transcriptome of L. chinensis under saline-alkaline treatment based on the 454-FLX massively parallel DNA sequencing platform. It also deepened studies on molecular mechanisms of saline-alkaline in L. chinensis, and constituted a database for future studies.
PMCID: PMC3554714  PMID: 23365637
21.  Expression of HGF and Met in Human Tissues of Colorectal Cancers: Biological and Clinical Implications for Synchronous Liver Metastasis 
Background and aims: Synchronous liver metastasis (SLM) remains a significant problem in newly diagnosed colorectal cancer (CRC). The system of hepatocyte growth factor (HGF) and Met plays an important role in cancer invasion and metastasis and is being developed to be targeted drugs. We aimed to investigate the role of HGF/Met in SLM based on a case-matched study and comparison between primary tumors and matched metastases.
Methods: A group of 30 patients with SLM and other two groups of patients without SLM in a hospital database were collected. They were matched into according to clinicopathological factors. 81 patients were included in the study. Their tissues of primary colorectal cancers, lymph nodes and liver metastases were collected to detect HGF and Met expression by immunohistochemistry and RT-PCR.
Results: Expression of HGF and Met at the protein level and the RNA level in primary CRCs with SLM were significantly higher than that in primary colorectal carcinomas without liver metastases (all P value<0.05). Their expression was only related to SLM when concurrent with regional lymph node metastasis (all P value<0.05) but had little influence on SLM without involvement of lymph node metastasis (all P value>0.05). Comparison their expression between primary tumors and matched metastases, major concordance and minor difference existed.
Conclusions: HGF and Met may exert functions in the development of SLM when concurrent with lymph node metastases but had little influence on SLM without lymph node metastasis, further indicating their roles and potential values for a subtype of colorectal cancer metastasis. Major concordance and minor difference exist between primary tumors and matched metastases, which further provides evidence for evaluating the response to their inhibitors based on primary tumors or metastases.
PMCID: PMC3607240  PMID: 23532910
colorectal carcinoma; synchronous liver metastasis; hepatocyte growth factor; Met.
22.  Overexpression of DOC-1R Inhibits Cell Cycle G1/S Transition by Repressing CDK2 Expression and Activation 
DOC-1R (deleted in oral cancer-1 related) is a novel putative tumor suppressor. This study investigated DOC-1R antitumor activity and the underlying molecular mechanisms. Cell phenotypes were assessed using flow cytometry, BrdU incorporation and CDK2 kinase assays in DOC-1R overexpressing HeLa cells. In addition, RT-PCR and Western blot assays were used to detect underlying molecular changes in these cells. The interaction between DOC-1R and CDK2 proteins was assayed by GST pull-down and immunoprecipitation-Western blot assays. The data showed that DOC-1R overexpression inhibited G1/S phase transition, DNA replication and suppressed CDK2 activity. Molecularly, DOC-1R inhibited CDK2 expression at the mRNA and protein levels, and there were decreased levels of G1-phase cyclins (cyclin D1 and E) and elevated levels of p21, p27, and p53 proteins. Meanwhile, DOC-1R associated with CDK2 and inhibited CDK2 activation by obstructing its association with cyclin E and A. In conclusion, the antitumor effects of DOC-1R may be mediated by negatively regulating G1 phase progression and G1/S transition through inhibiting CDK2 expression and activation.
PMCID: PMC3683939  PMID: 23781148
DOC-1R; CDK2; G1/S transition; cyclin E; cyclin A; CKI.
23.  Phylogeographic Study of Apodemus ilex (Rodentia: Muridae) in Southwest China 
PLoS ONE  2012;7(2):e31453.
The Mountains of southwest China have complex river systems and a profoundly complex topography and are among the most important biodiversity hotspots in the world. However, only a few studies have shed light on how the mountains and river valleys promote genetic diversity. Apodemus ilex is a fine model for investigating this subject.
Methodology/Principal Findings
To assess the genetic diversity and biogeographic patterns of Apodemus ilex, the complete cytochrome b gene sequences (1,140 bp) were determined from 203 samples of A. draco/ilex that were collected from southwest China. The results obtained suggested that A. ilex and A. draco are sistergroups and diverged from each other approximately 2.25 million years ago. A. ilex could be divided into Eastern and Western phylogroups, each containing two sub-groups and being widespread in different geographical regions of the southern Hengduan Mountains and the western Yunnan - Guizhou Plateau. The population expansions of A. ilex were roughly from 0.089 Mya to 0.023 Mya.
Our result suggested that A. ilex is a valid species rather than synonym of A. draco. As a middle-high elevation inhabitant, the phylogenetic pattern of A. ilex was strongly related to the complex geographical structures in southwest China, particularly the existence of deep river valley systems, such as the Mekong and Salween rivers. Also, it appears that the evolutionary history of A. ilex, such as lineage divergences and population expansions were strongly affected by climate fluctuation in the Late Pleistocene.
PMCID: PMC3274519  PMID: 22347481
24.  Structural and Binding Analysis of Pyrimidinol Carboxylic Acid and N-Hydroxy Quinazolinedione HIV-1 RNase H Inhibitors▿ 
HIV-1 RNase H breaks down the intermediate RNA-DNA hybrids during reverse transcription, requiring two divalent metal ions for activity. Pyrimidinol carboxylic acid and N-hydroxy quinazolinedione inhibitors were designed to coordinate the two metal ions in the active site of RNase H. High-resolution (1.4 Å to 2.1 Å) crystal structures were determined with the isolated RNase H domain and reverse transcriptase (RT), which permit accurate assessment of the metal and water environment at the active site. The geometry of the metal coordination suggests that the inhibitors mimic a substrate state prior to phosphodiester catalysis. Surface plasmon resonance studies confirm metal-dependent binding to RNase H and demonstrate that the inhibitors do not bind at the polymerase active site of RT. Additional evaluation of the RNase H site reveals an open protein surface with few additional interactions to optimize active-site inhibitors.
PMCID: PMC3101433  PMID: 21464257
25.  Changes of Serum Trace Elements, AFP, CEA, SF, T3, T4 and IGF-II in Different Periods of Rat Liver Cancer 
Based on liver cancer model built in SD rats, the contents of trace elements (Cu, Fe, Zn, Ca and Mg), AFP, CEA, SF, TH and IGF-II in serum were measured at different stages to explore the molecular changes during the rat liver cancer development.
The SD rat liver cancer model was built by using diethylnitrosamine (DENA) as the mutagen. During 16 weeks of DENA gavage, blood samples were taken in the 14th, 28th, 56th, 77th, 105th and 112th days respectively after the first day of gavage with DENA, then the contents of five trace elements (Cu, Fe, Zn, Ca and Mg), T3, T4, IGF-II, AFP, CEA and SF in serum were determined.
During the development of the rat liver cancer, in the test group, the Cu content significantly increased in serum, while the contents of Fe, Zn and Ca significantly decreased. The content of Mg showed no significant change. AFP and CEA of the test group showed same expression level with the control group; while the content of SF was lower than that of the control group when cancerization appeared. T3 and T4 increased at the first stage and then went down, and the content of IGF-II was always high.
Cu, Fe, Zn, Ca, T3, T4, SF and IGF-II are closely related to the development of liver cancer. The changes of their contents in the development of cancer could enlighten the researches on cancer pathogenesis and prevention.
PMCID: PMC3551310  PMID: 23357927
DENA; SD rats; Liver cancer; Trace elements; Biochemical components

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