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Benfey PN, Ren L, Chua NH. The CaMV 35S enhancer contains at least two domains which can confer different developmental and tissue-specific expression patterns. EMBO J 1989; 8:2195-202. [PMID: 16453896 PMCID: PMC401147 DOI: 10.1002/j.1460-2075.1989.tb08342.x] [Citation(s) in RCA: 284] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
We have analyzed expression conferred by two domains from the cauliflower mosaic virus (CaMV) 35S promoter and found different patterns in seeds, seedlings and seven week old plants. Expression from domain A (-90 to +8) is strongest in the radicle of the embryo, the radicle pole of the endosperm and in root tissue of seedlings and mature plants. Expression from domain B (-343 to -90) is strongest in the cells adjacent the cotyledon of the endosperm, in the cotyledons of the embryo and seedings and in the leaves and stem of mature plants. When both domain A and domain B are present expression is detectable in most tissues at all stages of development. Thus analysis of a constitutive promoter in transgenic plants can be used to identify cis elements that confer tissue specific and developmentally regulated expression.
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Zhang ZY, Jia GQ, Zuo JJ, Zhang Y, Lei J, Ren L, Feng DY. Effects of constant and cyclic heat stress on muscle metabolism and meat quality of broiler breast fillet and thigh meat. Poult Sci 2012; 91:2931-7. [PMID: 23091152 DOI: 10.3382/ps.2012-02255] [Citation(s) in RCA: 226] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study investigated the effects of constant and cyclic heat stress on muscle metabolism and meat quality of broiler breast fillet and thigh meat from 4 to 6 wk of age. Male Arbor Acres (AA) broilers (n = 270, 4 wk old) were raised under different temperature conditions: standard (temperature was 23°C); constant high temperature (temperature was 34°C); and cyclic high temperature (temperature was 36°C from 1000 h to 1600 h and 23°C from 1600 h to 1000 h). On d 42, broilers were stunned and sampled. The results showed that chronic high temperature significantly decreased the proportion of breast muscle and significantly increased the proportion of thigh muscle (P < 0.05). The moisture concentration was significantly higher in the breast muscle of the birds exposed to constant high temperature (P < 0.05), whereas the protein content was significantly lower (P < 0.05) and fat deposition was significantly higher (P < 0.05) in the breast muscle of the birds exposed to constant or diurnal cyclic high temperature than those grown under standard temperature. The breast and thigh muscle of the birds grown under constant high temperature had significantly higher lightness, cook loss, and shear force (P < 0.05) and significantly lower initial pH (pH(i)), ultimate pH (pH(u)), and redness compared with those grown under standard temperature (P < 0.05). The pH(i), pH(u), and redness were significantly lower (P < 0.05) while the lightness and shear force were significantly higher for the breast muscle of the chickens raised under diurnal cyclic high temperature (P < 0.05) than those grown under standard temperature. In contrast, lightness and yellowness of thigh muscle were significantly higher (P < 0.05) in the chickens grown under diurnal cyclic high temperature than under standard temperature. Breast and thigh muscle of broilers exposed to constant high temperature produced higher (P < 0.05) lactic acid and pyruvate kinase activities than those exposed to the standard temperature. These results indicated that chronic heat stress significantly increased lactate production, reduced meat pH value by accelerating meat glycolysis, and eventually reduced meat quality.
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Benfey PN, Ren L, Chua NH. Tissue-specific expression from CaMV 35S enhancer subdomains in early stages of plant development. EMBO J 1990; 9:1677-84. [PMID: 2347301 PMCID: PMC551870 DOI: 10.1002/j.1460-2075.1990.tb08291.x] [Citation(s) in RCA: 198] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The cauliflower mosaic virus (CaMV) 35S enhancer is able to confer strong constitutive expression in plants. We have previously defined two domains within this enhancer that can confer different tissue-specific expression patterns throughout development. We show here that the upstream domain (B) has a modular organization. It contains at least five subdomains that are able to confer distinct expression patterns when fused to the downstream domain (A). When fused to a minimal promoter only three of the five subdomains give any expression in the early stages of plant development. Comparison of the expression patterns conferred by the subdomains alone, in combination with the downstream domain or in combination with other subdomains provides evidence for synergistic interactions among cis-elements within the 35S enhancer.
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Ohi MD, Link AJ, Ren L, Jennings JL, McDonald WH, Gould KL. Proteomics analysis reveals stable multiprotein complexes in both fission and budding yeasts containing Myb-related Cdc5p/Cef1p, novel pre-mRNA splicing factors, and snRNAs. Mol Cell Biol 2002; 22:2011-24. [PMID: 11884590 PMCID: PMC133674 DOI: 10.1128/mcb.22.7.2011-2024.2002] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2001] [Revised: 09/19/2001] [Accepted: 12/20/2001] [Indexed: 11/20/2022] Open
Abstract
Schizosaccharomyces pombe Cdc5p and its Saccharomyces cerevisiae ortholog, Cef1p, are essential Myb-related proteins implicated in pre-mRNA splicing and contained within large multiprotein complexes. Here we describe the tandem affinity purification (TAP) of Cdc5p- and Cef1p-associated complexes. Using transmission electron microscopy, we show that the purified Cdc5p complex is a discrete structure. The components of the S. pombe Cdc5p/S. cerevisiae Cef1p complexes (termed Cwfs or Cwcs, respectively) were identified using direct analysis of large protein complex (DALPC) mass spectrometry (A. J. Link et al., Nat. Biotechnol. 17:676-682, 1999). At least 26 proteins were detected in the Cdc5p/Cef1p complexes. Comparison of the polypeptides identified by S. pombe Cdc5p purification with those identified by S. cerevisiae Cef1p purification indicates that these two yeast complexes are nearly identical in composition. The majority of S. pombe Cwf proteins and S. cerevisiae Cwc proteins are known pre-mRNA splicing factors including core Sm and U2 and U5 snRNP components. In addition, the complex contains the U2, U5, and U6 snRNAs. Previously uncharacterized proteins were also identified, and we provide evidence that several of these novel factors are involved in pre-mRNA splicing. Our data represent the first comprehensive analysis of CDC5-associated proteins in yeasts, describe a discrete highly conserved complex containing novel pre-mRNA splicing factors, and demonstrate the power of DALPC for identification of components in multiprotein complexes.
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Sun B, Zhou W, Li H, Ren L, Qiao P, Li W, Fu H. Synthesis of Particulate Hierarchical Tandem Heterojunctions toward Optimized Photocatalytic Hydrogen Production. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1804282. [PMID: 30272827 DOI: 10.1002/adma.201804282] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/05/2018] [Indexed: 05/11/2023]
Abstract
Photocatalytic hydrogen production using semiconductors is identified as one of the most promising routes for sustainable energy; however, it is challenging to harvest the full solar spectrum in a particulate photocatalyst for high activity. Herein, a hierarchical hollow black TiO2 /MoS2 /CdS tandem heterojunction photocatalyst, which allows broad-spectrum absorption, thus delivering enhanced hydrogen evolution performance is designed and synthesized. The MoS2 nanosheets not only function as a cost-effective cocatalyst but also act as a bridge to connect two light-harvesting semiconductors into a tandem heterojunction where the CdS nanoparticles and black TiO2 spheres absorb UV and visible light on both sides efficiently, coupling with the MoS2 cocatalyst into a particulate photocatalyst system. Consequently, the photocatalytic hydrogen rate of the black TiO2 /MoS2 /CdS tandem heterojunction is as high as 179 µmol h-1 per 20 mg photocatalyst under visible-light irradiation, which is almost 3 times higher than that of black TiO2 /MoS2 heterojunctions (57.2 µmol h-1 ). Most importantly, the stability of CdS nanoparticles in the black TiO2 /MoS2 /CdS tandem heterojunction is greatly improved compared to MoS2 /CdS because of the formation of tandem heterojunctions and the strong UV-absorbing effect of black TiO2 . Such a tandem architectural design provides new ways for synthesizing particulate photocatalysts with high efficiencies.
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Liu Q, Wang RS, Qu GQ, Wang YY, Liu P, Zhu YZ, Fei G, Ren L, Zhou YW, Liu L. Gross examination report of a COVID-19 death autopsy. FA YI XUE ZA ZHI 2020; 36:21-23. [PMID: 32198987 DOI: 10.12116/j.issn.1004-5619.2020.01.005] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Indexed: 12/14/2022]
Abstract
Abstract
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Takatsuji H, Mori M, Benfey PN, Ren L, Chua NH. Characterization of a zinc finger DNA-binding protein expressed specifically in Petunia petals and seedlings. EMBO J 1992; 11:241-9. [PMID: 1740109 PMCID: PMC556445 DOI: 10.1002/j.1460-2075.1992.tb05047.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
In Petunia, the expression of the 5-enolpyruvylshikimate-3-phosphate synthase gene (EPSPS) is tissue-specific and developmentally regulated. Nuclear extracts from Petunia petal contain a factor that interacts with the 5' upstream region of EPSPS. DNase I footprinting experiments revealed four strong binding sites (EP1-EP4) and several weaker sites that appear to bind the same factor. We have isolated a cDNA clone (EPF1) encoding a DNA-binding protein that has similar binding activity to that of the nuclear factor. The deduced amino acid sequence shows that the encoded protein, EPF1, contains two repeats of a Cys2/His2 zinc finger motif. EPF1 and the factor detected in nuclear extracts appear to differ in their molecular weight and Zn2+ requirements. Nevertheless, Northern blot analyses showed that the expression pattern of EPF1 is remarkably similar to that of EPSPS. In addition, as determined by translational fusion of the EPF1 upstream region to the beta-glucuronidase reporter gene, the cell specific expression pattern of EPF1 in flower and seedling is nearly identical to that of EPSPS. Taken together with the results of cis-element analyses, these observations suggest that EPF1 may be one of the factors involved in the activation of EPSPS.
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Ren L, Gonzalez R, Wang Z, Xiang Z, Wang Y, Zhou H, Li J, Xiao Y, Yang Q, Zhang J, Chen L, Wang W, Li Y, Li T, Meng X, Zhang Y, Vernet G, Paranhos-Baccalà G, Chen J, Jin Q, Wang J. Prevalence of human respiratory viruses in adults with acute respiratory tract infections in Beijing, 2005-2007. Clin Microbiol Infect 2009; 15:1146-53. [PMID: 19456830 PMCID: PMC7129754 DOI: 10.1111/j.1469-0691.2009.02746.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To determine the aetiological role and epidemiological profile of common respiratory viruses in adults with acute respiratory tract infections (ARTIs), a 2-year study was conducted in Beijing, China, from May 2005 to July 2007. Nose and throat swab samples from 5808 ARTI patients were analysed by PCR methods for common respiratory viruses, including influenza viruses (IFVs) A, B, and C, parainfluenza viruses (PIVs) 1-4, enteroviruses (EVs), human rhinoviruses (HRVs), respiratory syncytial virus (RSV), human metapneumovirus (HMPV), human coronaviruses (HCoVs) OC43, 229E, NL63, and HKU1, and adenoviruses (ADVs). Viral pathogens were detected in 34.6% of patient samples, and 1.6% of the patients tested positive for more than one virus. IFVs (19.3%) were the dominant agents detected, followed by HRVs (6.5%), PIVs (4.3%), EVs (3.2%), and HCoVs (1.1%). ADVs, RSV and HMPV were also detected (<1%). The viral detection rates differed significantly between infections of the lower and upper respiratory tracts in the sample population: PIVs, the second most commonly detected viral agents in lower acute respiratory tract infections (LRTIs), were more prevalent than in upper acute respiratory tract infections, indicating that the pathogenic role of PIVs in LRTIs should be investigated. Currently, this study is the largest-scale investigation of respiratory virus infections in China with multiple agent detection, providing baseline data for further studies of respiratory virus infections in adults with ARTIs.
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Research Support, Non-U.S. Gov't |
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Abstract
We have analyzed expression conferred by five subdomains of the cauliflower mosaic virus (CaMV) 35S enhancer in mature transgenic plants. Expression was detected from subdomains that gave no expression at earlier stages of development indicating developmental regulation of expression and confirming the modular organization of the enhancer. In several cases the expression patterns are highly restricted in cell type, providing useful markers for developmental studies. Comparison of expression patterns conferred by various combinations of 35S enhancer cis-elements suggests that synergistic interactions among cis-elements may play an important role in defining tissue-specific expression. This has implications for the nature of a cis-element combinatorial code that could define expression throughout development.
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Tanriover B, Mohan S, Cohen DJ, Radhakrishnan J, Nickolas TL, Stone PW, Tsapepas DS, Crew RJ, Dube GK, Sandoval PR, Samstein B, Dogan E, Gaston RS, Tanriover JN, Ratner LE, Hardy MA, Chvojka J, da Motta H, Devan J, Dytman SA, Díaz GA, Eberly B, Felix J, Fields L, Fiorentini GA, Gago AM, Gallagher H, Gran R, Harris DA, Higuera A, Hurtado K, Jerkins M, Kafka T, Kordosky M, Kulagin SA, Le T, Maggi G, Maher E, Manly S, Mann WA, Marshall CM, Martin Mari C, McFarland KS, McGivern CL, McGowan AM, Miller J, Mislivec A, Morfín JG, Muhlbeier T, Naples D, Nelson JK, Norrick A, Osta J, Palomino JL, Paolone V, Park J, Patrick CE, Perdue GN, Rakotondravohitra L, Ransome RD, Ray H, Ren L, Rodrigues PA, Savage DG, Schellman H, Schmitz DW, Simon C, Snider FD, Solano Salinas CJ, Tagg N, Valencia E, Velásquez JP, Walton T, Wolcott J, Zavala G, Zhang D, Ziemer BP. Kidneys at higher risk of discard: expanding the role of dual kidney transplantation. Am J Transplant 2014; 14:404-15. [PMID: 24472195 PMCID: PMC4058786 DOI: 10.1111/ajt.12553] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 10/15/2013] [Accepted: 10/15/2013] [Indexed: 01/25/2023]
Abstract
Half of the recovered expanded criteria donor (ECD) kidneys are discarded in the United States. A new kidney allocation system offers kidneys at higher risk of discard, Kidney Donor Profile Index (KDPI)>85%, to a wider geographic area to promote broader sharing and expedite utilization. Dual kidney transplantation (DKT) based on the KDPI is a potential option to streamline allocation of kidneys which otherwise would have been discarded. To assess the clinical utility of the KDPI in kidneys at higher risk of discard, we analyzed the OPTN/UNOS Registry that included the deceased donor kidneys recovered between 2002 and 2012. The primary outcomes were allograft survival, patient survival and discard rate based on different KDPI categories (<80%, 80-90% and >90%). Kidneys with KDPI>90% were associated with increased odds of discard (OR=1.99, 95% CI 1.74-2.29) compared to ones with KDPI<80%. DKTs of KDPI>90% were associated with lower overall allograft failure (HR=0.74, 95% CI 0.62-0.89) and better patient survival (HR=0.79, 95% CI 0.64-0.98) compared to single ECD kidneys with KDPI>90%. Kidneys at higher risk of discard may be offered in the up-front allocation system as a DKT. Further modeling and simulation studies are required to determine a reasonable KDPI cutoff percentile.
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Ren L, Li D, Qu W. Electro-Viscous Effects on Liquid Flow in Microchannels. J Colloid Interface Sci 2001; 233:12-22. [PMID: 11112301 DOI: 10.1006/jcis.2000.7262] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The presence of the electrical double layer near a solid-liquid interface results in the electro-viscous effect on pressure-driven liquid flow through microchannels. The objective of this paper is to examine the magnitude of the additional flow resistance caused by the electrokinetic effect in microchannels. Deionized ultrafiltered water, 10(-4) and 10(-2) M aqueous KCl solutions, 10(-4) M AlCl(3) solution, and 10(-4) M LiCl solution were used as the testing liquids. Carefully designed flow measurements were conducted in three silicon microchannels with a height of 14.1, 28.2, and 40.5 µm, respectively. The measured dP/dx for the pure water, the 10(-4) M KCl solution, and the 10(-4) M LiCl solution was found to be significantly higher than the prediction of the conventional laminar flow theory at the same Reynolds number. Such a high flow resistance and the resulting high apparent viscosity strongly depend on the channel's height, the ionic valence, and the concentration of the liquids. The zeta potentials for the liquid-solid systems were calculated by using the measured streaming potential data. The experimentally determined dP/dx approximately Re relationships were compared with the predictions of a theoretical electro-viscous flow model, and a good agreement was found for pure water, 10(-4) M KCl solution, and 10(-4) MAlCl(3) solution systems. The present electrokinetic flow model cannot interpret the flow characteristics of the LiCl solution. Copyright 2001 Academic Press.
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Ren L, Martin CH, Wise KJ, Gillespie NB, Luecke H, Lanyi JK, Spudich JL, Birge RR. Molecular mechanism of spectral tuning in sensory rhodopsin II. Biochemistry 2001; 40:13906-14. [PMID: 11705380 DOI: 10.1021/bi0116487] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sensory rhodopsin II (SRII) is unique among the archaeal rhodopsins in having an absorption maximum near 500 nm, blue shifted roughly 70 nm from the other pigments. In addition, SRII displays vibronic structure in the lambda(max) absorption band, whereas the other pigments display fully broadened band maxima. The molecular origins responsible for both photophysical properties are examined here with reference to the 2.4 A crystal structure of sensory rhodopsin II (NpSRII) from Natronobacterium pharaonis. We use semiempirical molecular orbital theory (MOZYME) to optimize the chromophore within the chromophore binding site, and MNDO-PSDCI molecular orbital theory to calculate the spectroscopic properties. The entire first shell of the chromophore binding site is included in the MNDO-PSDCI SCF calculation, and full single and double configuration interaction is included for the chromophore pi-system. Through a comparison of corresponding calculations on the 1.55 A crystal structure of bacteriorhodopsin (bR), we identify the principal molecular mechanisms, and residues, responsible for the spectral blue shift in NpSRII. We conclude that the major source of the blue shift is associated with the significantly different positions of Arg-72 (Arg-82 in bR) in the two proteins. In NpSRII, this side chain has moved away from the chromophore Schiff base nitrogen and closer to the beta-ionylidene ring. This shift in position transfers this positively charged residue from a region of chromophore destabilization in bR to a region of chromophore stabilization in NpSRII, and is responsible for roughly half of the blue shift. Other important contributors include Asp-201, Thr-204, Tyr-174, Trp-76, and W402, the water molecule hydrogen bonded to the Schiff base proton. The W402 contribution, however, is a secondary effect that can be traced to the transposition of Arg-72. Indeed, secondary interactions among the residues contribute significantly to the properties of the binding site. We attribute the increased vibronic structure in NpSRII to the loss of Arg-72 dynamic inhomogeneity, and an increase in the intensity of the second excited (1)A(g)(-) -like state, which now appears as a separate feature within the lambda(max) band profile. The strongly allowed (1)B(u)(+)-like state and the higher-energy (1)A(g)(-) -like state are highly mixed in NpSRII, and the latter state borrows intensity from the former to achieve an observable oscillator strength.
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Tang Y, Kong L, Wu F, Womer F, Jiang W, Cao Y, Ren L, Wang J, Fan G, Blumberg HP, Xu K, Wang F. Decreased functional connectivity between the amygdala and the left ventral prefrontal cortex in treatment-naive patients with major depressive disorder: a resting-state functional magnetic resonance imaging study. Psychol Med 2013; 43:1921-1927. [PMID: 23194671 DOI: 10.1017/s0033291712002759] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Convergent studies provide support for abnormalities in the structure and functioning of the prefrontal cortex (PFC) and the amygdala, the key components of the neural system that subserves emotional processing in major depressive disorder (MDD). We used resting-state functional magnetic resonance imaging (fMRI) to examine potential amygdala-PFC functional connectivity abnormalities in treatment-naive subjects with MDD. METHODS Resting-state fMRI data were acquired from 28 individuals with MDD and 30 healthy control (HC) subjects. Amygdala-PFC functional connectivity was compared between the MDD and HC groups. RESULTS Decreased functional connectivity to the left ventral PFC (VPFC) from the left and right amygdala was observed in the MDD group, compared with the HC group (p < 0.05, corrected). CONCLUSIONS The treatment-naive subjects with MDD showed decreased functional connectivity from the amygdala to the VPFC, especially to the left VPFC. This suggests that these connections may play an important role in the neuropathophysiology of MDD at its onset.
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Research Support, N.I.H., Extramural |
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Gould KL, Ren L, Feoktistova AS, Jennings JL, Link AJ. Tandem affinity purification and identification of protein complex components. Methods 2005; 33:239-44. [PMID: 15157891 DOI: 10.1016/j.ymeth.2003.11.019] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2003] [Indexed: 11/23/2022] Open
Abstract
As with the budding yeast Saccharomyces cerevisiae, the completion of the Schizosaccharomyces pombe genome sequence has opened new opportunities to investigate the functional organization of a eukaryotic cell. These include analysis of gene expression patterns, comprehensive gene knockout and synthetic lethal screens, global protein localization analysis, and direct protein interaction mapping. We describe here the tandem affinity purification or TAP approach combined with DALPC mass spectrometry to identify components of protein complexes as we have applied it to S. pombe. This approach can theoretically be applied to the entire proteome as has been done in S. cerevisiae to gain insight into functional protein assemblies and to elucidate functions of uncharacterized proteins.
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Research Support, U.S. Gov't, P.H.S. |
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Koblin BA, Torian LV, Guilin V, Ren L, MacKellar DA, Valleroy LA. High prevalence of HIV infection among young men who have sex with men in New York City. AIDS 2000; 14:1793-800. [PMID: 10985317 DOI: 10.1097/00002030-200008180-00015] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the prevalence of HIV infection and risk behaviors among young men who have sex with men (MSM) aged 15-22 years in New York City. DESIGN An anonymous cross-sectional survey. METHODS The 1998 Young Men's Survey in New York City (YMS-NYC), was a multistage probability survey of 541 MSM aged 15-22 years who attend public venues. After identification of venues and their associated high attendance time periods, random samples of venues and time periods were selected on a monthly basis. At each sampling event, potential participants were approached to determine eligibility. Eligible and willing men were interviewed, counselled and had a blood specimen drawn. RESULTS Between December 1997 and September 1998, 115 sampling events were conducted. Of 612 men enrolled, 541 reported ever having had sex with a male partner. The HIV seroprevalence among the 541 MSM sampled was 12.1%. The HIV seroprevalence was 18.4% among African-Americans, 16.7% among persons of mixed race, 8.8% among Latino individuals and 3.1% among white men. HIV seroprevalence was 5.0% among 15-18 year olds and 16.4% among 19-22 year olds. A total of 65.5% of MSM were susceptible to hepatitis B virus infection (HBV). Almost half (46.1%) of the men reported unprotected anal sex in the previous 6 months and 16.3% reported ever having had an STD. Multiple regression analyses found that being older, of mixed race, black or ever having had an STD was associated with being HIV antibody positive. CONCLUSION These data identify a large subgroup of MSM in need of effective HIV and HBV primary and secondary prevention programs.
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Seidman AD, Portenoy R, Yao TJ, Lepore J, Mont EK, Kortmansky J, Onetto N, Ren L, Grechko J, Beltangady M. Quality of life in phase II trials: a study of methodology and predictive value in patients with advanced breast cancer treated with paclitaxel plus granulocyte colony-stimulating factor. J Natl Cancer Inst 1995; 87:1316-22. [PMID: 7544834 DOI: 10.1093/jnci/87.17.1316] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Despite the clinical benefit that may be associated with reduction of tumor volume, chemotherapy may produce physical or psychological distress that could compromise a patient's quality of life. Although palliation may be as relevant as tumor response in patients with metastatic breast cancer, quality of life is not commonly evaluated in phase II clinical trials of new therapeutic agents. PURPOSE We evaluated the utility of quality-of-life assessment in two phase II clinical trials of patients receiving paclitaxel (Taxol) and recombinant human granulocyte colony-stimulating factor (rhG-CSF) as salvage therapy for metastatic breast cancer. METHODS A battery of instruments (i.e., Memorial Symptom Assessment Scale [MSAS], Functional Living Index-Cancer [FLIC], Rand Mental Health Inventory [MHI], Brief Pain Inventory [BPI], and Memorial Pain Assessment Card [MPAC]) designed to capture information about social, psychological, and functional aspects of quality of life, as well as symptom prevalence and distress, was completed prior to treatment; serial assessments were obtained at regular intervals during the treatment period. Univariate and multivariate analyses were performed evaluating base-line quality-of-life parameters and standard prognostic factors in relation to outcome measures of survival, tumor response, and toxicity. For 30 consecutive patients with extensive prior chemotherapy for metastatic disease, longitudinal data were analyzed associating tumor response to changes in quality-of-life scores throughout the course of treatment with paclitaxel. RESULTS Base-line scores of two validated quality-of-life instruments, the MSAS and the FLIC, independently predicted the overall survival (P < .01 for each). In this model, however, neither standard prognostic factors nor quality of life instruments predicted the likelihood of tumor response or the probability of encountering grade 3 or grade 4 nonhematologic toxicity. With serial assessments of quality of life, the majority of patients who achieved partial tumor response or stable disease reported improved or unchanged quality-of-life scores, while those patients with progressive disease experienced rapid deterioration in quality of life. CONCLUSIONS Base-line quality-of-life assessment may provide prognostic information distinct from that obtained through standard prognostic indicators alone. The combination of two factors--extent of disease and a base-line quality-of-life assessment--predicted survival more accurately than either used separately. Evaluation of quality-of-life outcomes in relation to tumor response may illuminate previously unmeasured palliative effects of chemotherapy, such as pain relief, as well as the burdens it imposes. IMPLICATIONS Information obtained from quality-of-life assessment in conjunction with phase II testing of new chemotherapeutic agents for metastatic breast cancer can guide quality-of-life evaluation planned in large, randomized future studies.
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Ren L, Lubrich B, Biber K, Gebicke-Haerter PJ. Differential expression of inflammatory mediators in rat microglia cultured from different brain regions. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1999; 65:198-205. [PMID: 10064890 DOI: 10.1016/s0169-328x(99)00016-9] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Microglial cells show a rather uniform distribution of cell numbers throughout the brain with only minor prevalences in some brain regions. Their in situ morphologies, however, may vary markedly from elongated forms observed in apposition with neuronal fibers to spherical cell bodies with sometimes extremely elaborated branching. This heterogeneity gave rise to the hypothesis that these cells are differentially conditioned by their microenvironment and, therefore, also display specific patterns of differential gene expression. In this study, microglia were isolated from 2-4 week-old mixed CNS cultures that had been prepared from neonatal rat diencephalon, tegmentum, hippocampus, cerebellum and cerebral cortex, and were investigated 24 h later. Messenger RNA levels of proteins involved in crucial immune functions of this cell type (TNF-alpha, CD4, Fcgamma receptor II, and IL-3 receptor beta-subunit) have been determined by semi-quantitative RT-PCR. The results clearly show, that three of these mRNAs (TNF-alpha, CD4, Fcgamma receptor II) are differentially expressed in microglia with hippocampal microglia displaying the highest levels of these mRNAs. The data strongly support the notion that the status of microglial gene expression depends on their localization in brain and on specific interactions with other neural cell types. Consequently, it is hypothesized that their responsiveness to signals arising in injury or disease may vary from one brain region to another.
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Comparative Study |
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74 |
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Wang X, Zuo D, Chen Y, Li W, Liu R, He Y, Ren L, Zhou L, Deng T, Wang X, Ying G, Ba Y. Shed Syndecan-1 is involved in chemotherapy resistance via the EGFR pathway in colorectal cancer. Br J Cancer 2014; 111:1965-76. [PMID: 25321193 PMCID: PMC4229635 DOI: 10.1038/bjc.2014.493] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/30/2014] [Accepted: 08/13/2014] [Indexed: 01/03/2023] Open
Abstract
Background: Syndecan-1 (Sdc-1) shedding induced by matrix metalloproteinase-7 (MMP-7) and additional proteases has an important role in cancer development. However, the impact of Sdc-1 shedding on chemotherapeutic resistance has not been reported. Methods: We examined Sdc-1 shedding in colorectal cancer by enzyme-linked immunosorbent assay (ELISA), Dot blot, reverse transcription-PCR (RT-PCR), immunohistochemistry and so on, its impact on chemotherapeutic sensitivity by collagen gel droplet embedded culture-drug sensitivity test (CD-DST) and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide), and potential mechanisms of action by Dot blot, western blot and immunofluorescence. Results: Sdc-1 shedding was increased in colorectal cancer patients, Sdc-1 serum levels in postoperative patients were lower than in preoperative patients, but still higher than those observed in healthy adults. Patients with high preoperative Sdc-1 serum levels were less responsive to 5-Fluorouracil, Oxaliplatin, Irintecan, Cisplatin or Paclitaxel chemotherapy. Moreover, the disease-free survival of patients with high preoperative Sdc-1 serum levels was significantly poorer. The possible mechanism of chemotherapy resistance in colorectal cancer can be attributed to Sdc-1 shedding, which enhances EGFR phosphorylation and downstream signalling. Conclusions: Shed Sdc-1 is involved in chemotherapy resistance via the EGFR pathway in colorectal cancer, and Sdc-1 serum levels could be a new prognostic marker in colorectal cancer.
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Research Support, Non-U.S. Gov't |
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72 |
19
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Ohi MD, Vander Kooi CW, Rosenberg JA, Ren L, Hirsch JP, Chazin WJ, Walz T, Gould KL. Structural and functional analysis of essential pre-mRNA splicing factor Prp19p. Mol Cell Biol 2005; 25:451-60. [PMID: 15601865 PMCID: PMC538785 DOI: 10.1128/mcb.25.1.451-460.2005] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
U-box-containing Prp19p is an integral component of the Prp19p-associated complex (the nineteen complex, or NTC) that is essential for activation of the spliceosome. Prp19p makes numerous protein-protein contacts with other NTC components and is required for NTC stability. Here we show that Prp19p forms a tetramer in vitro and in vivo and we map the domain required for its oligomerization to a central tetrameric coiled-coil. Biochemical and in vivo analyses are consistent with Prp19p tetramerization providing an interaction surface for a single copy of its binding partner, Cef1p. Electron microscopy showed that the isolated Prp19p tetramer is an elongated particle consisting of four globular WD40 domains held together by a central stalk consisting of four N-terminal U-boxes and four coiled-coils. These structural and functional data provide a basis for understanding the role of Prp19p as a key architectural component of the NTC.
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Research Support, U.S. Gov't, P.H.S. |
20 |
72 |
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Ren L, Marquardt MA, Lech JJ. Estrogenic effects of nonylphenol on pS2, ER and MUC1 gene expression in human breast cancer cells-MCF-7. Chem Biol Interact 1997; 104:55-64. [PMID: 9158695 DOI: 10.1016/s0009-2797(97)03767-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Many chemicals have recently been discovered to have estrogenic activity, including the surfactant intermediate nonylphenol (NP). It has been well documented that estrogen is a facilitator of human breast cancer development under certain conditions, and environmental estrogens such as NP are currently under intense investigation. Using the expression of pS2 (a trefoil peptide expressed in breast cancer cells), MUC1 (a member of the mucin family) and ER (the human estrogen receptor) genes as estrogen-responsive reporter genes, the effects of estradiol and NP on human breast cancer cells-MCF-7 were studied. In the time course study, the mRNA expressions were detected after NP (10 microM) or estradiol (E2, 0.1 microM) treatments using the RT-PCR technique. The results indicated: (1) NP and E2 induced pS2 mRNA expression after a 2-h exposure and (2) NP induction produced the highest level of MUC1 mRNA after 2 h, which was reduced to only 42% of control at 48 h. E2 treatment resulted in a gradual increase in MUC1 expression over the course of the exposure. The highest level of MUC1 mRNA was at 48 h. This indicates that NP may stimulate MUC1 expression by a different mechanism than E2. (3) NP affected ER expression in the same manner as MUC1. In contrast, E2 stimulated ER expression in a similar manner as pS2; the highest level was at 2 h and expression remained elevated through the 48-h point. NP is an estrogenic compound that alters pS2, MUC1 and ER gene expression in MCF-7 cells. NP may affect MUC1 expression through a different mechanism than E2. The link between aberrant MUC1, PS2 and ER expression and the development of breast cancer also needs to be elucidated through further investigation.
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28 |
65 |
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Grossman HB, Wedemeyer G, Ren L, Wilson GN, Cox B. Improved growth of human urothelial carcinoma cell cultures. J Urol 1986; 136:953-9. [PMID: 3761468 DOI: 10.1016/s0022-5347(17)45139-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
From January, 1981 through June, 1982 specimens from 21 patients with bladder (urothelial) cancer were placed in tissue culture, and one long term cell line was established (5%). From July, 1982 through February, 1984, using an improved culture medium, seven long term cell cultures were established from 21 patients (33%). In addition, one long term culture from a patient with a bladder melanoma was established using the standard culture medium. The nine cell cultures were derived from the following types of tumors: transitional cell carcinoma (6), adenocarcinoma (1), squamous cell carcinoma (1) and melanoma (1). All of the cell lines have produced tumors in athymic nude mice except for one transitional cell carcinoma. All of the cultures demonstrate aneuploidy. Homogeneously staining regions have been seen in some cell cultures. A common marker chromosome has not been identified.
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Ren L, Sun J, Chen S, Gao J, Dong B, Liu Y, Xia X, Wang Y, Liao Y, Teng N, Fang W, Guan Z, Chen F, Jiang J. A transcriptomic analysis of Chrysanthemum nankingense provides insights into the basis of low temperature tolerance. BMC Genomics 2014; 15:844. [PMID: 25277256 PMCID: PMC4197275 DOI: 10.1186/1471-2164-15-844] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 09/23/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A major constraint affecting the quality and productivity of chrysanthemum is the unusual period of low temperature occurring during early spring, late autumn, and winter. Yet, there has been no systematic investigation on the genes underlying the response to low temperature in chrysanthemum. Herein, we used RNA-Seq platform to characterize the transcriptomic response to low temperature by comparing different transcriptome of Chrysanthemum nankingense plants and subjecting them to a period of sub-zero temperature, with or without a prior low temperature acclimation. RESULTS Six separate RNA-Seq libraries were generated from the RNA samples of leaves and stems from six different temperature treatments, including one cold acclimation (CA), two freezing treatments without prior CA, two freezing treatments with prior CA and the control. At least seven million clean reads were obtained from each library. Over 77% of the reads could be mapped to sets of C. nankingense unigenes established previously. The differentially transcribed genes (DTGs) were identified as low temperature sensing and signalling genes, transcription factors, functional proteins associated with the abiotic response, and low temperature-responsive genes involved in post-transcriptional regulation. The differential transcription of 15 DTGs was validated using quantitative RT-PCR. CONCLUSIONS The large number of DTGs identified in this study, confirmed the complexity of the regulatory machinery involved in the processes of low temperature acclimation and low temperature/freezing tolerance.
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research-article |
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Zhao L, Meng Q, Ren L, Liu W, Zhang X, Huo Y, Zhou Z. Effects of Nitrate Addition on Rumen Fermentation, Bacterial Biodiversity and Abundance. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2015; 28:1433-41. [PMID: 26194220 PMCID: PMC4554850 DOI: 10.5713/ajas.15.0091] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 03/06/2015] [Accepted: 03/25/2015] [Indexed: 11/27/2022]
Abstract
This study examined changes of rumen fermentation, ruminal bacteria biodiversity and abundance caused by nitrate addition with Ion Torrent sequencing and real-time polymerase chain reaction. Three rumen-fistulated steers were fed diets supplemented with 0%, 1%, and 2% nitrate (dry matter %) in succession. Nitrate supplementation linearly increased total volatile fatty acids and acetate concentration obviously (p = 0.02; p = 0.02; p<0.01), butyrate and isovalerate concentration numerically (p = 0.07). The alpha (p>0.05) and beta biodiversity of ruminal bacteria were not affected by nitrate. Nitrate increased typical efficient cellulolytic bacteria species (Ruminococcus flavefaciens, Ruminococcus ablus, and Fibrobacter succinogenes) (p<0.01; p = 0.06; p = 0.02). Ruminobactr, Sphaerochaeta, CF231, and BF311 genus were increased by 1% nitrate. Campylobacter fetus, Selenomonas ruminantium, and Mannheimia succiniciproducens were core nitrate reducing bacteria in steers and their abundance increased linearly along with nitrate addition level (p<0.01; p = 0.02; p = 0.04). Potential nitrate reducers in the rumen, Campylobacter genus and Cyanobacteria phyla were significantly increased by nitrate (p<0.01; p = 0.01). To the best of our knowledge, this was the first detailed view of changes in ruminal microbiota by nitrate. This finding would provide useful information on nitrate utilization and nitrate reducer exploration in the rumen.
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Journal Article |
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Zhou J, Teng J, Ren L, Wang Y, Liu Z, Liu W, Yang W, Xie Z. Full-crystalline hierarchical monolithic ZSM-5 zeolites as superiorly active and long-lived practical catalysts in methanol-to-hydrocarbons reaction. J Catal 2016. [DOI: 10.1016/j.jcat.2016.05.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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9 |
56 |
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Singh NS, Shao N, McLean JR, Sevugan M, Ren L, Chew TG, Bimbo A, Sharma R, Tang X, Gould KL, Balasubramanian MK. SIN-inhibitory phosphatase complex promotes Cdc11p dephosphorylation and propagates SIN asymmetry in fission yeast. Curr Biol 2011; 21:1968-78. [PMID: 22119525 PMCID: PMC4167312 DOI: 10.1016/j.cub.2011.10.051] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 10/13/2011] [Accepted: 10/28/2011] [Indexed: 10/15/2022]
Abstract
BACKGROUND Cytokinesis in many eukaryotes involves the function of an actomyosin-based contractile ring. In fission yeast, actomyosin ring maturation and stability require a conserved signaling pathway termed the SIN (septation initiation network). The SIN consists of a GTPase (Spg1p) and three protein kinases, all of which localize to the mitotic spindle pole bodies (SPBs). Two of the SIN kinases, Cdc7p and Sid1p, localize asymmetrically to the newly duplicated SPB in late anaphase. How this asymmetry is achieved is not understood, although it is known that their symmetric localization impairs cytokinesis. RESULTS Here we characterize a new Forkhead-domain-associated protein, Csc1p, and identify SIN-inhibitory PP2A complex (SIP), which is crucial for the establishment of SIN asymmetry. Csc1p localizes to both SPBs early in mitosis, is lost from the SPB that accumulates Cdc7p, and instead accumulates at the SPB lacking Cdc7p. Csc1p is required for the dephosphorylation of the SIN scaffolding protein Cdc11p and is thereby required for the recruitment of Byr4p, a component of the GTPase-activating subunit for Spg1p, to the SPB. CONCLUSIONS Because Cdc7p does not bind to GDP-Spg1p, we propose that the SIP-mediated Cdc11p dephosphorylation and the resulting recruitment of Byr4p are among the earliest steps in the establishment of SIN asymmetry.
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Research Support, Non-U.S. Gov't |
14 |
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