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Rong Lu

Publications and source records attributed to Rong Lu.

At least 19 recordsLinked to original sources
PubMed2026

Systematic identification pepper CaE2F transcription factor reveals the role of CaDPb in drought stress response.

The EARLY 2 FACTOR (E2F) transcription factor (TF) family plays a pivotal role in regulating plant development and adaptations to environmental stresses. However, the physiological function of E2Fs in pepper (Capsicum annuum L.) are not well elucidated. In this work, we conduct a comprehensive genome-wide annotation of the E2F family within the Zunla-1 pepper genome and further explore the biological roles of CaDPb in response to drought stress. Through systematic bioinformatics analysis, we identify a total of nine CaE2F genes within the Zunla-1 genome, categorizing them into three distinct subgroups. Additionally, we discover multiple cis-regulatory elements in the CaE2F promoter regions associated with responses to plant hormones and drought stress. Public RNA-seq datasets reveal distinct expression profiles of CaE2F genes across various pepper tissues and their responses to environmental stimuli and plant hormones. Subsequently, the CaDPb gene is further functionally verified in drought response. Our findings indicate that TRV2:CaDPb silenced pepper plants are more sensitivity to drought. Furthermore, we show that CaDPb participates in the regulation of reactive oxygen species (ROS) production, the expression of drought-responsive genes, and the modulation of stomatal aperture. Taken together, our findings provide a comprehensive characterization of E2F genes in pepper and offer insights into the biological function of CaDPb in pepper drought stress response.

Capsicum↗
PubMed2026

An immune-associated mitochondrial DNA variant with sex differences reveals a putative novel microprotein called MASL.

The use of mitochondrial wide association studies (MiWAS) to link mitochondrial DNA variants (mtSNPs) to phenotypes of interest has uncovered important connections between mitochondrial genes and human health. The recent introduction of a re-annotated mitochondrial genome that accounts for small open reading frames (sORFs) with protein coding potential suggests the existence of mitochondrial-derived microproteins, many of which remain uncharacterized. Thus, considering the re-annotated mitochondrial genome when conducting genomic analyses such as MiWAS facilitates the mapping of mtSNPs back to microprotein-encoding sORFs and uncovers interactions between mitochondrial microproteins and biological systems. Here, we employ MiWAS of venous blood samples from the Health and Retirement Study (HRS) and identify a mtSNP associated with sex-specific changes to immune composition. After accounting for re-annotation, we map the identified mtSNP back to a sORF that encodes a novel microprotein, termed MASL (Mitochondrial Associated Small d-Loop peptide). Complementary phenome-wide association studies (PheWAS) in HRS and and UK Biobank confirm interactions between this mtSNP and immune phenotypes of interest, and our targeted RNA-Seq method (mitoSNP-seq) elucidates sex-differences in gene expression and functional pathways potentially altered by this mtSNP that may be relevant to the associated microprotein. Early characterization of the MASL microprotein shows sex-differences in circulating MASL levels in human plasma, and sex-specific interactions when comparing male and female mice treated with synthesized MASL. Together, the results of this study not only contribute to our understanding of mitochondrial dynamics in immunity, but also provide early characterization of a novel mitochondrial-derived microprotein with sex-specific modulatory effects.

Genomics↗
PubMed2006

A meta-analysis: comparison of esomeprazole and other proton pump inhibitors in eradicating Helicobacter pylori.

BACKGROUND: To assess effects of esomeprazole-based therapies and others (PPIs) on Helicobacter pylori eradication when co-administered with antibiotics. GOALS: Using the terms 'H. pylori eradication' and 'esomeprazole', we searched Medline, Embase, and the Cochrane Library (2000-2005) and conducted a manual search of related Chinese journals to identify randomized controlled trials (RCTs) that compared the treatment effects of esomeprazole and other PPI therapies in patients with H. pylori infection. RESULTS: Of the 75 articles screened, 11 RCTs including 2,159 subjects were included in the meta-analysis. The mean H. pylori eradication rates (intention-to-treat, ITT) with esomeprazole + antibiotics was 86%, a rate comparable with other PPI therapies, 81% (ITT); the odds ratio (OR) was 1.38 (95% CI = 1.09-1.75). A focused meta-analysis of 6 selected high-quality studies was produced an OR of this comparison that was closer to one (1.17, 95% CI = 0.89-1.54), with the results being statistically homogeneous. Sub-analysis that included only studies comparing different does of esomeprazole with omeprazole or pantoprazole did not reveal significant differences. No additional serious adverse events were reported. CONCLUSIONS: Esomeprazole-based triple therapy may effectively eradicate H. pylori infection and promote favorable outcome with good tolerance and offers comparable efficacy to omeprazole-based therapy.

Anti-Bacterial Agents↗
PubMed2006

Dissecting self-renewal in stem cells with RNA interference.

We present an integrated approach to identify genetic mechanisms that control self-renewal in mouse embryonic stem cells. We use short hairpin RNA (shRNA) loss-of-function techniques to downregulate a set of gene products whose expression patterns suggest self-renewal regulatory functions. We focus on transcriptional regulators and identify seven genes for which shRNA-mediated depletion negatively affects self-renewal, including four genes with previously unrecognized roles in self-renewal. Perturbations of these gene products are combined with dynamic, global analyses of gene expression. Our studies suggest specific biological roles for these molecules and reveal the complexity of cell fate regulation in embryonic stem cells.

Animals↗
PubMed2006

Expression of PTEN, p27, p21 and AKT mRNA and protein in human BEL-7402 hepatocarcinoma cells in transplanted tumors of nude mice treated with the tripeptide tyroservatide (YSV).

The tripeptide, tyroservatide (YSV), has been previously shown to have antitumor effects through unknown mechanism. In the current study, we examined whether YSV modulates the protumorigenic PI3K pathway in human BEL-7402 hepatocarcinoma cells. BEL-7402 hepatocarcinoma was transplanted into the subcutaneous tissues of nude mice, and YSV, at varying doses, was administered. RT-PCR and Western blot were used to analyze the expression of PTEN, AKT, p21 and p27. YSV at doses of 80 microg/kg/day, 160 microg/kg/day and 320 microg/kg/day markedly inhibited the growth of human BEL-7402 hepatocarcinoma (p < 0.05). YSV increased mRNA and protein expression of the tumor-suppressor genes, PTEN, p21 and p27, and inhibited the mRNA and protein expression of the oncogene AKT. Furthermore, YSV administration was associated with dephosphorylation of both PTEN (which activates PTEN) and AKT (which inhibits AKT). These results are consistent with the possibility that YSV mediates inhibition of tumor growth through inhibition of the PI3K pathway and suggests that YSV should be explored for use as an antitumor agent for hepatocarcinoma.

Animals↗
PubMed2006

Regulation of hMSH2 and hMLH1 expression in the human colon cancer cell line SW1116 by DNA methyltransferase 1.

Aberrant DNA methylation is now recognized as an important epigenetic alteration occurring early in human cancer. To directly study the role of DNA methyltransferase 1 (DNMT1) in the regulation of expression of tumor-related genes in human colon cancer cells, we stably transfected expression constructs containing sense or antisense DNMT1 into the human colon cancer cell line, SW1116. The expression level of mismatch repair genes (MMR), human mut-L homologue 1 (hMLH1) and human Mut S homologue 2 (hMSH2), was monitored by real-time RT-PCR. The methylation status of hMLH1 and hMSH2 promoters was determined by bisulfite modification and methylation-specific PCR (MSP). The protein levels of DNMT1, hMSH2 and hMLH1 were determined by Western analysis. The results show that DNMT1 protein expression was increased or decreased in transfected cell lines containing sense or antisense DNMT1 constructs, respectively. In cells expressing the sense DNMT1 construct, the expression of hMLH1 and hMSH2 was down-regulated through hypermethylation of their respective promoters. Furthermore, antisense DNMT1 expression induced promoter demethylation and up-regulated transcription of hMSH2 (P<0.05) and hMLH1 (P=0.064) in SW1116 cells.

Adaptor Proteins, Signal Transducing↗
PubMed2006

A practical approach to optimization and validation of a HPLC assay for analysis of polyribosyl-ribitol phosphate in complex combination vaccines.

The use of multi-factor statistical experimental design methodology minimized the vaccine material and laboratory resources required for optimization and validation of an HPLC assay for quantitation of depolymerized and total PRP. Components of the assay selected for optimization were adjuvant dissolution, ultracentrifuge conditions including ultracentrifuge model, sample diluent, mobile phase and column oven temperature. Previous experience has shown these components of the assay to be most troublesome and therefore required optimization prior to validation. Specificity, linearity, precision, accuracy and ruggedness were confirmed through a validation of the optimized assay. The validation also established the assay to be stability indicating, by showing that changes to the integrity of the PRP-OMPC conjugate could be detected.

Chromatography, High Pressure Liquid↗
PubMed2006

Gene-chip analysis of the effect of tripeptide tyroservatide (YSV) on gene-expression in human hepatocarcinoma BEL-7402 tumors transplanted to nude mice.

Tyroservatide (YSV) is a bioactive tripeptide of tyrosyl-seryl-valine. In this study, we studied the effects of YSV on human hepatocarcinoma BEL-7402 tumors transplanted in BALB/c (nu/nu) nude mice, and gene expression in the tumor cells with gene-chip analysis. Results show that YSV significantly inhibits the growth of transplanted human hepatocarcinoma BEL-7402 in nude mice (n = 12) compared with the control group (P < 0.05); with an inhibition rate of 55% at 320 microg/kg/d. Seven hundred eighty-one genes were different between the YSV group and the control group. Fifty-two genes changed in expression level by onefold or more including 37 downregulated genes and 15 upregulated genes. Probably, YSV exhibits a significant antitumor activity by inhibiting the expression of tumor cells histone genes, then damaging tumor cell chromosome and killing tumor cells.

Animals↗
PubMed2006

[Inhibitory effect of tripeptide compound tyroservaltide on invasion and metastasis of mouse melanoma cell line B16-F10].

BACKGROUND & OBJECTIVE: Tripeptide compound tyroservaltide (YSV) has obvious inhibitory effect on experimental liver cancer. This study was to evaluate the inhibitory effect of YSV on the invasion and metastasis of mouse melanoma cell line B16-F10. METHODS: The cytotoxic effect of YSV on B16-F10 cells was assessed by MTT assay, and the effects of YSV on the adhesiveness and invasiveness of B16-F10 cells were determined using Matrigel and a transwell system. B16-F10 cells were injected into the tail veins of C57BL/6 mice to establish an experimental lung metastasis model, and the effect of YSV on lung metastasis was observed. The effect of YSV on the expression of intercellular adhesion molecule-1 (ICAM-1) in lung tissue was detected by immunohistochemistry. RESULTS: YSV (100 microg/ml, 48 h) inhibited the proliferation of B16-F10 cells, with an inhibitory rate of 24.36%; YSV (100 microg/ml, 24 h) inhibited the adhesiveness of B16-F10 cells to Matrigel, with an inhibitory rate of 36.51%; YSV (10 microg/ml, 48 h) inhibited the invasiveness of B16-F10 cells, with an inhibitory rate of 36.53%; YSV [640 microg.(kg.d)-1] inhibited lung metastasis by B16-F10 cells, with an inhibitory rate of 62.21%. The expression of ICAM-1 in lung tissue was lower in YSV group than in normal saline group. CONCLUSION: YSV can inhibit the growth, invasion, and metastasis of B16-F10 cells.

Animals↗
PubMed2005

Simultaneous determination of ZT-1 and its metabolite Huperzine A in plasma by high-performance liquid chromatography with ultraviolet detection.

ZT-1 is a novel acetylcholinesterase (AChE) inhibitor. It is rapidly transformed to Huperzine A (Hup A) in vitro. A simple and rapid HPLC-UV method for the simultaneous determination of ZT-1 and its metabolite Hup A in plasma is described. The chromatographic separations were achieved on a C(18) ODS column (250 mm x 4.6 mm ID) using methanol-1 mmol/L ammonium acetate (70:30,v/v) as mobile phase. The flow rate was 0.7 mL/min, the detection wavelength was 313 nm and the column temperature was kept at 35 degrees C. Plasma samples were prepared as rapidly as possible and extracted immediately with 5 mL of chloroform:iso-propyl alcohol mixture (v/v, 9:1). The retention times of ZT-1 and Huperzine A (Hup A) were 18.7 and 14.4 min, respectively. The mean absolute recoveries of two analytes were >90%. Quantification limits were all 0.02 nmol/mL for ZT-1 and Hup A. This analytical method was reliable and convenient procedure that meets the criteria for the pharmacokinetic evaluation of ZT-1 on experimental animals.

Alkaloids↗
PubMed2005

Tripeptide tyroserleutide enhances the antitumor effects of macrophages and stimulates macrophage secretion of IL-1beta, TNF-alpha, and NO in vitro.

Tyroserleutide (YSL) is a type of active, low molecular weight polypeptide, comprised of three amino acids, which has antitumor effects. YSL has various advantages over the other bioactive peptides such as its low molecular weight, simple construction, nonimmunogenicity, specificity, few side effects, and ease of synthesis. However, the biological activities contributing to it's antitumor effects are not yet known. We studied the effects of YSL on the in vitro cytotoxic activity of BALB/c mice peritoneal macrophages (PEMphi) against the target tumor cell lines BEL-7402 and B16-F10. We also measured the concentrations of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and nitric oxide (NO) produced by YSL-activated Mphi, and we determined the concentrations of IL-1beta and NO secreted by YSL-activated murine macrophage RAW264.7 cells. YSL activated Mphi in vitro, inhibited BEL-7402 proliferation, enhanced PEMphi antitumor effects, and stimulated IL-1beta, TNF-alpha, and NO production by RAW264.7 cells. These data suggest that YSL activates the monocyte-macrophage system, which enhances Mphi antitumor effects against BEL-7402 and B16-F10 cells and stimulates the secretion by Mphi of cytotoxic effectors such as IL-1beta, TNF-alpha, and NO.

Animals↗
PubMed2005

MaxiK channel partners: physiological impact.

The basic functional unit of the large-conductance, voltage- and Ca2+-activated K+ (MaxiK, BK, BKCa) channel is a tetramer of the pore-forming alpha-subunit (MaxiKalpha) encoded by a single gene, Slo, holding multiple alternative exons. Depending on the tissue, MaxiKalpha can associate with modulatory beta-subunits (beta1-beta4) increasing its functional diversity. As MaxiK senses and regulates membrane voltage and intracellular Ca2+, it links cell excitability with cell signalling and metabolism. Thus, MaxiK is a key regulator of vital body functions, like blood flow, uresis, immunity and neurotransmission. Epilepsy with paroxysmal dyskinesia syndrome has been recognized as a MaxiKalpha-related disorder caused by a gain-of-function C-terminus mutation. This channel region is also emerging as a key recognition module containing sequences for MaxiKalpha interaction with its surrounding signalling partners, and its targeting to cell-specific microdomains. The growing list of interacting proteins highlights the possibility that associations with the C-terminus of MaxiKalpha are dynamic and depending on each cellular environment. We speculate that the molecular multiplicity of the C-terminus (and intracellular loops) dictated by alternative exons may modulate or create additional interacting sites in a tissue-specific manner. A challenge is the dissection of MaxiK macromolecular signalling complexes in different tissues and their temporal association/dissociation according to the stimulus.

Animals↗
PubMed2005

Preliminary investigation of the inhibitory effects of the tyroservaltide (YSV) tripeptide on human hepatocarcinoma BEL-7402.

This study aimed to investigate the inhibitory effect of tyroservaltide (YSV) on the human hepatocarcinoma BEL-7402 transplanted into nude mice and to explore its possible anti-tumor mechanism. Nude mice bearing xenografts of the human BEL-7402 hepatoma were given daily i.p. injections of YSV or saline (as a control) after the tumor were transplanted. Calculating tumor volume and measuring tumor weight determined the extent of inhibition of xenografts. The ultrastructure of tumor cells was observed by electron microscopy. Proliferating cell nuclear antigen (PCNA) expression in tissues of the YSV-treated group was observed by immunohistochemistry. Apoptosis of tumor tissue cells was assayed by the terminal transferase uridyl nick end labeling (TUNEL) method. At doses of 80 microg/kg/d and 160 microg/kg/d, YSV could significantly inhibit growth of tumors transplanted into nude mice, with inhibition rates of 60% and 64%, respectively, compared with that of the controls (P < 0.05). Moreover, YSV changed the ultrastructure of tumor cells, resulting in necrosis and apoptosis of the tumor cells. Compared with the saline group, the expression of PCNA in tumor tissue decreased and the count of apoptotic cell increased. Therefore, YSV can significantly inhibit the growth of human hepatocarcinoma BEL-7402 in nude mice, decrease the expression of PCNA in tumor tissue, and induce tumor cell apoptosis.

Animals↗
PubMed2005

[Induction of epidermal stem cells of rhesus monkey into human conjunctival epithelial cells: an in vitro experiment].

OBJECTIVE: To observe the possibility of inducing the epidermal stem cells of rhesus monkey into human conjunctival epithelial cells and to investigate the plasticity of epidermal stem cells. METHODS: Epidermal stem cells of rhesus monkey were cultured in vitro and separated with type IV collagen. The cells were analyzed before and after isolation with beta1 integrin and keratin 15 by flow cytometry. The separated stem cells were characterized with markers, beta1 integrin and keratin 15 by immunohistochemistry and RT-PCR. The stem cells were transfected by green fluorescent protein (GFP) gene. 24 hours later, the fluorescent cells were selected out and co-cultured with human conjunctival epithelial cells in Transwell for 10 days. Then the cells were characterized with the markers of beta1 integrin, keratin 15, mucin 4 and keratin 4 by immunohistochemistry and RT-PCR. RESULTS: The purity of the separated epidermal stem cells was almost 90%, and all the cells were positive of beta1 integrin and keratin 15. After being transfected with GFP gene for 24 hours, the cells expressed green fluorescence. 10 days later, after co-culture with human conjunctival epithelial cells, the epidermal stem cells were positive of mucin 4 and keratin 4. CONCLUSION: Epidermal stem cells of rhesus monkey can be induced into conjunctival epithelial cells in vitro by co-culturing with primary passage conjunctival epithelial cells.

Animals↗
PubMed2005

The effect of tripeptide tyroserleutide (YSL) on animal models of hepatocarcinoma.

This study aimed to observe the effects of tyroserleutide (tyrosyl-seryl-leucine, YSL) on the survival time of mice transplanted with the ascitic fluid-type hepatocarcinoma H22, as well as the inhibitory effect of tyroserleutide on the human hepatocarcinoma Bel-7402 that was transplanted into nude mice. At doses of 80, 20 and 5 microg/kg/d, tyroserleutide significantly prolonged the survival of mice transplanted with H22 tumor cells, producing survival rates of 89%, 39% and 49%, respectively, which were statistically significantly different from the saline group (P < 0.05). YSL, at doses of 80, 160 and 320 microg/kg/d significantly inhibited the growth of the human hepatocarcinoma Bel-7402 tumor in nude mice, producing inhibition of 40%, 64% and 59%, respectively; this inhibition was significantly greater than that by saline (P < 0.05). HE staining and electron microscopy of the pathological changes of the tumor in nude mice showed that YSL changed the structure Bel-7402 tumor cells that were transplanted into nude mice, and also induced tumor cell apoptosis and necrosis, which could be a mechanism by which YSL inhibits the tumor growth in animal models.

Animals↗
PubMed2005

C-H stretching vibrations of methyl, methylene and methine groups at the vapor/alcohol (N = 1-8) interfaces.

In IR and Raman spectral studies, the congestion of the vibrational modes in the C-H stretching region between 2800 and 3000 cm(-1) has complicated spectral assignment, conformational analysis, and structural and dynamics studies, even with quite a few of the simplest molecules. To resolve these issues, polarized spectra measurement on a well aligned sample is generally required. Because the liquid interface is generally ordered and molecularly thin, and sum frequency generation vibrational spectroscopy (SFG-VS) is an intrinsically coherent polarization spectroscopy, SFG-VS can be used for discerning details in vibrational spectra of the interfacial molecules. Here we show that, from systematic molecular symmetry and SFG-VS polarization analysis, a set of polarization selection rules could be developed for explicit assignment of the SFG vibrational spectra of the C-H stretching modes. These polarization selection rules helped assignment of the SFG-VS spectra of vapor/alcohol (n = 1-8) interfaces with unprecedented details. Previous approach on assignment of these spectra relied on IR and Raman spectral assignment, and they were not able to give such detailed assignment of the SFG vibrational spectra. Sometimes inappropriate assignment was made, and consequently misleading conclusions on interfacial structure, conformation and even dynamics were reached. With these polarization rules in addition to knowledge from IR and Raman studies, new structural information and understanding of the molecular interactions at these interfaces were obtained, and some new spectral features for the C-H stretching modes were also identified. Generally speaking, these new features can be applied to IR and Raman spectroscopic studies in the condensed phase. Therefore, the advancement on vibrational spectra assignment may find broad applications in the related fields using IR and Raman as vibrational spectroscopic tools.

2-Propanol↗
PubMed2005

Experimental study of the inhibition of human hepatocarcinoma Bel7402 cells by the tripeptide tyroserleutide(YSL).

PURPOSE: To investigate the antitumor effects of tyroserleutide (tyrosyl-seryl-leucine, YSL) on human Bel7402 hepatocarcinoma in vitro and in vivo, with preliminary exploration of its antitumor mechanism. METHODS: MTT was used to observe the anticarcinogenic effects of YSL on human hepatocarcinoma Bel7402 cells in vitro. The ultrastructure of tumor cells was observed by electron microscopy. Nude mice bearing xenografts of human hepatocarcinoma Bel7402 were given daily i.p. injections of YSL or saline and an admixture of amino acids as controls, after tumor implantation. The inhibition of xenografts was determined by calculating the tumor volume and measuring tumor weight. The effects of YSL on the cell cycle and apoptosis of Bel7402 cells were determined by flow cytometry, and the effects on the ultrastructure of the cells by electron microscopy. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and proliferating-cell nuclear antigen (PCNA) immunohistochemical staining were used to investigate apoptosis in tumor tissue in nude mice. RESULTS: In vitro YSL inhibited the proliferation of human Bel7402 tumor cells and changed their ultrastructure, resulting in the necrosis and apoptosis of the tumor cells. YSL at 80, 160, or 320 microg/kg/d inhibited tumor growth in nude mice by 40.26, 64.17, and 59.19%, respectively, which are significantly lower than the inhibition exerted by saline and an admixture of YSL amino acids (P<0.05). The ultrastructure and cell cycle of human hepatocarcinoma Bel7402 cells were changed by treatment with YSL, with a rate of apoptosis higher than that of the control group. TUNEL and PCNA analysis showed that YSL inhibited the proliferation of tumor cells and induced apoptosis at the level of the cell. CONCLUSIONS: YSL significantly inhibited human hepatocarcinoma Bel7402 growth in vitro and in vivo. The growth inhibition of the tumor may involve necrosis and apoptosis of the tumor induced by YSL.

Animals↗