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Pulmonary Fibroblasts Stimulate The Proliferation Of Cell Lines From Human Lung Adenocarcinomas, Maria Cekanova, T Masi, Howard Plummer, M Majidi, P Fedorocko, Hildegard Schuller Aug 2011

Pulmonary Fibroblasts Stimulate The Proliferation Of Cell Lines From Human Lung Adenocarcinomas, Maria Cekanova, T Masi, Howard Plummer, M Majidi, P Fedorocko, Hildegard Schuller

Howard K. Plummer III

Human lung cancer cell lines are widely used to test anticancer drugs. These in-vitro tests, however, preclude the detection of responses to paracrine factors from surrounding stroma. We have cocultured pulmonary fibroblasts CCD-19Lu, from a healthy donor, or HLF-A, from a patient with epidermoid carcinoma of the lung, with two human pulmonary adenocarcinoma cell lines to test the hypothesis that the fibroblasts stimulate the growth of the tumor cells. Both fibroblast cell lines significantly increased the proliferation of the pulmonary adenocarcinoma cell lines in 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide assays, with HLF-A fibroblasts yielding the most pronounced responses ...


Alternative Probeset Definitions For Combining Microarray Data Across Studies Using Different Versions Of Affymetrix Oligonucleotide Arrays, Jeffrey S. Morris, Chunlei Wu, Kevin R. Coombes, Keith A. Baggerly, Jing Wang, Li Zhang Dec 2006

Alternative Probeset Definitions For Combining Microarray Data Across Studies Using Different Versions Of Affymetrix Oligonucleotide Arrays, Jeffrey S. Morris, Chunlei Wu, Kevin R. Coombes, Keith A. Baggerly, Jing Wang, Li Zhang

Jeffrey S. Morris

Many published microarray studies have small to moderate sample sizes, and thus have low statistical power to detect significant relationships between gene expression levels and outcomes of interest. By pooling data across multiple studies, however, we can gain power, enabling us to detect new relationships. This type of pooling is complicated by the fact that gene expression measurements from different microarray platforms are not directly comparable. In this chapter, we discuss two methods for combining information across different versions of Affymetrix oligonucleotide arrays. Each involves a new approach for combining probes on the array into probesets. The first approach involves ...


Prepms: Tof Ms Data Graphical Preprocessing Tool, Yuliya V. Karpievitch, Elizabeth G. Hill, Adam J. Smolka, Jeffrey S. Morris, Kevin R. Coombes, Keith A. Baggerly, Jonas S. Almeida Nov 2006

Prepms: Tof Ms Data Graphical Preprocessing Tool, Yuliya V. Karpievitch, Elizabeth G. Hill, Adam J. Smolka, Jeffrey S. Morris, Kevin R. Coombes, Keith A. Baggerly, Jonas S. Almeida

Jeffrey S. Morris

We introduce a simple-to-use graphical tool that enables researchers to easily prepare time-of-flight mass spectrometry data for analysis. For ease of use, the graphical executable provides default parameter settings experimentally determined to work well in most situations. These values can be changed by the user if desired. PrepMS is a stand-alone application made freely available (open source), and is under the General Public License (GPL). Its graphical user interface, default parameter settings, and display plots allow PrepMS to be used effectively for data preprocessing, peak detection, and visual data quality assessment.


The Exoribonuclease Xrn4 Is A Component Of The Ethylene Response Pathway In Arabidopsis, Brad Binder, Thomas Potuschak, Amérin Vansiri, Esther Lechner, Richard Vierstra, Pascal Genschik Oct 2006

The Exoribonuclease Xrn4 Is A Component Of The Ethylene Response Pathway In Arabidopsis, Brad Binder, Thomas Potuschak, Amérin Vansiri, Esther Lechner, Richard Vierstra, Pascal Genschik

Brad M. Binder

EXORIBONUCLEASE4 (XRN4), the Arabidopsis thaliana homolog of yeast XRN1, is involved in the degradation of several unstable mRNAs. Although a role for XRN4 in RNA silencing of certain transgenes has been reported, xrn4 mutant plants were found to lack any apparent visible phenotype. Here, we show that XRN4 is allelic to the unidentified components of the ethylene response pathway ETHYLENE-INSENSITIVE5/ACC-INSENSITIVE1 (EIN5/AIN1) and EIN7. xrn4 mutant seedlings are ethylene-insensitive as a consequence of the upregulation of EIN3 BINDING F-BOX PROTEIN1 (EBF1) and EBF2 mRNA levels, which encode related F-box proteins involved in the turnover of EIN3 protein, a crucial ...


Ethylene-Stimulated Nutations Do Not Require Etr1 Receptor Histidine Kinase Activity, Brad Binder Oct 2006

Ethylene-Stimulated Nutations Do Not Require Etr1 Receptor Histidine Kinase Activity, Brad Binder

Brad M. Binder

Ethylene influences the growth and development of plants through the action of receptors that have homology to bacterial two-component receptors. In bacteria these receptors function via autophosphorylation of a His residue in the kinase domain followed by phosphotransfer to a conserved Asp residue in a response regulator protein. In Arabidopsis, two of the five receptor isoforms are capable of His kinase activity. However, the role of His kinase activity and phosphotransfer is unclear in ethylene signaling. A previous study showed that ethylene stimulates nutations of the hypocotyl in etiolated Arabidopsis seedlings that are dependent on the ETR1 receptor isoform. The ...


A Genomic Approach To Identify Regulatory Nodes In The Transcriptional Network Of Systemic Acquired Resistance In Plants, Dong Wang, Nita Amornsiripanitch, Xinnian Dong Oct 2006

A Genomic Approach To Identify Regulatory Nodes In The Transcriptional Network Of Systemic Acquired Resistance In Plants, Dong Wang, Nita Amornsiripanitch, Xinnian Dong

Dong Wang

Many biological processes are controlled by intricate networks of transcriptional regulators. With the development of microarray technology, transcriptional changes can be examined at the whole-genome level. However, such analysis often lacks information on the hierarchical relationship between components of a given system. Systemic acquired resistance (SAR) is an inducible plant defense response involving a cascade of transcriptional events induced by salicylic acid through the transcription cofactor NPR1. To identify additional regulatory nodes in the SAR network, we performed microarray analysis on Arabidopsis plants expressing the NPR1-GR (glucocorticoid receptor) fusion protein. Since nuclear translocation of NPR1-GR requires dexamethasone, we were able ...


Reconstitution Of Protein Targeting To The Inner Envelope Membrane Of Chloroplasts, Ming Li, Danny Schnell Oct 2006

Reconstitution Of Protein Targeting To The Inner Envelope Membrane Of Chloroplasts, Ming Li, Danny Schnell

Danny Schnell

The chloroplast envelope plays critical roles in the synthesis and regulated transport of key metabolites, including intermediates in photosynthesis and lipid metabolism. Despite this importance, the biogenesis of the envelope membranes has not been investigated in detail. To identify the determinants of protein targeting to the inner envelope membrane (IM), we investigated the targeting of the nucleus-encoded integral IM protein, atTic40. We found that pre-atTic40 is imported into chloroplasts and processed to an intermediate size (int-atTic40) before insertion into the IM. Int-atTic40 is soluble and inserts into the IM from the internal stromal compartment. We also show that atTic40 and ...


Nnk Activates Erk1/2 And Creb/Atf-1 Via Beta-1-Ar And Egfr Signaling In Human Lung Adenocarcinoma And Small Airway Epithelial Cells, E Laag, M Majidi, Maria Cekanova, T Masi, T Takahashi, Hildegard Schuller Sep 2006

Nnk Activates Erk1/2 And Creb/Atf-1 Via Beta-1-Ar And Egfr Signaling In Human Lung Adenocarcinoma And Small Airway Epithelial Cells, E Laag, M Majidi, Maria Cekanova, T Masi, T Takahashi, Hildegard Schuller

Maria Cekanova MS, RNDr, PhD

We have shown that the tobacco nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is an agonist for -adrenergic receptors (beta-ARs) and increased DNA synthesis of human lung adenocarcinoma cells with features of bronchiolar Clara cells by binding to these receptors. Using a cell line derived from a human pulmonary adenocarcinoma with Clara cell phenotype (PACC) and immortalized human small airway epithelial cells (HPLD1), the putative cells of origin of this cancer type, our current studies have analyzed signaling initiated by binding of NNK to the beta 1-AR. NNK upregulated ERK1/2 and CREB/ATF-1 phosphorylation in a PKA-dependent manner in ...


The Structure Of Escherichia Coli Signal Recognition Particle Revealed By Scanning Transmission Electron Microscopy, Lain L. Mainprize, Daniel R. Beniac, Elena Falkovskaia, Robert M. Cleverley, Lila Gierasch, F. Peter Ottensmeyer, David W. Andrews Sep 2006

The Structure Of Escherichia Coli Signal Recognition Particle Revealed By Scanning Transmission Electron Microscopy, Lain L. Mainprize, Daniel R. Beniac, Elena Falkovskaia, Robert M. Cleverley, Lila Gierasch, F. Peter Ottensmeyer, David W. Andrews

Lila Gierasch

Structural studies on various domains of the ribonucleoprotein signal recognition particle (SRP) have not converged on a single complete structure of bacterial SRP consistent with the biochemistry of the particle. We obtained a three-dimensional structure for Escherichia coli SRP by cryoscanning transmission electron microscopy and mapped the internal RNA by electron spectroscopic imaging. Crystallographic data were fit into the SRP reconstruction, and although the resulting model differed from previous models, they could be rationalized by movement through an interdomain linker of Ffh, the protein component of SRP. Fluorescence resonance energy transfer experiments determined interdomain distances that were consistent with our ...


Pulmonary Fibroblasts Stimulate The Proliferation Of Cell Lines From Human Lung Adenocarcinomas, Maria Cekanova, T Masi, Howard Plummer, M Majidi, P Fedorocko, Hildegard Schuller Jul 2006

Pulmonary Fibroblasts Stimulate The Proliferation Of Cell Lines From Human Lung Adenocarcinomas, Maria Cekanova, T Masi, Howard Plummer, M Majidi, P Fedorocko, Hildegard Schuller

Maria Cekanova MS, RNDr, PhD

Human lung cancer cell lines are widely used to test anticancer drugs. These in-vitro tests, however, preclude the detection of responses to paracrine factors from surrounding stroma. We have cocultured pulmonary fibroblasts CCD-19Lu, from a healthy donor, or HLF-A, from a patient with epidermoid carcinoma of the lung, with two human pulmonary adenocarcinoma cell lines to test the hypothesis that the fibroblasts stimulate the growth of the tumor cells. Both fibroblast cell lines significantly increased the proliferation of the pulmonary adenocarcinoma cell lines in 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide assays, with HLF-A fibroblasts yielding the most pronounced responses ...


A Comprehensive Structure–Function Analysis Of Arabidopsis Sni1 Defines Essential Regions And Transcriptional Repressor Activity, Rebecca Mosher, Wendy Durrant, Dong Wang, Jungi Song, Xinnian Dong Jul 2006

A Comprehensive Structure–Function Analysis Of Arabidopsis Sni1 Defines Essential Regions And Transcriptional Repressor Activity, Rebecca Mosher, Wendy Durrant, Dong Wang, Jungi Song, Xinnian Dong

Dong Wang

The expression of systemic acquired resistance (SAR) in plants involves the upregulation of many Pathogenesis-Related (PR) genes, which work in concert to confer resistance to a broad spectrum of pathogens. Because SAR is a costly process, SAR-associated transcription must be tightly regulated. Arabidopsis thaliana SNI1 (for Suppressor of NPR1, Inducible) is a negative regulator of SAR required to dampen the basal expression of PR genes. Whole genome transcriptional profiling showed that in the sni1 mutant, Nonexpresser of PR genes (NPR1)–dependent benzothiadiazole S-methylester–responsive genes were specifically derepressed. Interestingly, SNI1 also repressed transcription when expressed in yeast, suggesting that it ...


Some Statistical Issues In Microarray Gene Expression Data, Matthew S. Mayo, Byron J. Gajewski, Jeffrey S. Morris Jun 2006

Some Statistical Issues In Microarray Gene Expression Data, Matthew S. Mayo, Byron J. Gajewski, Jeffrey S. Morris

Jeffrey S. Morris

In this paper we discuss some of the statistical issues that should be considered when conducting experiments involving microarray gene expression data. We discuss statistical issues related to preprocessing the data as well as the analysis of the data. Analysis of the data is discussed in three contexts: class comparison, class prediction and class discovery. We also review the methods used in two studies that are using microarray gene expression to assess the effect of exposure to radiofrequency (RF) fields on gene expression. Our intent is to provide a guide for radiation researchers when conducting studies involving microarray gene expression ...


Detection Of Overexpressed Cox-2 In Precancerous Lesions Of Hamster Pancreas And Lungs By Molecular Imaging: Implications For Early Diagnosis And Prevention, Hildegard Schuller, George Kabalka, G Smith, A Mereddy, M Akula, Maria Cekanova May 2006

Detection Of Overexpressed Cox-2 In Precancerous Lesions Of Hamster Pancreas And Lungs By Molecular Imaging: Implications For Early Diagnosis And Prevention, Hildegard Schuller, George Kabalka, G Smith, A Mereddy, M Akula, Maria Cekanova

Maria Cekanova MS, RNDr, PhD

The enzyme cyclooxygenase-2 (COX-2) is overexpressed in many cancers, cardiovascular disease, neurodegenerative disorders, and arthritis. Selective inhibitors of COX-2 have been developed as therapeutics or preventive agents for these diseases. However, recent reports have revealed a significant increase in cardiovascular mortality in long-term users of the COX-2 inhibitors Vioxx and Celebrex, emphasizing the need for noninvasive tests that allow the identification of individuals whose COX-2 levels are overexpressed prior to assignment to treatment with these drugs. In this study, we have prepared a radioiodinated analogue of the selective COX-2 inhibitor celecoxib, and verified its binding to the COX-2 enzyme in ...


Probability Of Real -Time Detection Vs Probability Of Infection For Aerosolized Biowarfare Agents: A Model Study., Alexander G. Sabelnikov, Vladimir Zhukov, C Ruth Kempf May 2006

Probability Of Real -Time Detection Vs Probability Of Infection For Aerosolized Biowarfare Agents: A Model Study., Alexander G. Sabelnikov, Vladimir Zhukov, C Ruth Kempf

Alexander G Sabelnikov

No abstract provided.


Biochemical Characterization Of The Major Sorghum Grain Peroxidase, Mamoudou H. Dicko, Harry Gruppen, Riet Hilhorst, Alphons G. J. Voragen, Willen W. H. Van Berkel Apr 2006

Biochemical Characterization Of The Major Sorghum Grain Peroxidase, Mamoudou H. Dicko, Harry Gruppen, Riet Hilhorst, Alphons G. J. Voragen, Willen W. H. Van Berkel

Pr. Mamoudou H. DICKO, PhD

The major cationic peroxidase in sorghum grain (SPC4) , which is ubiquitously present in all sorghum varieties was purified to apparent homogeneity, and found to be a highly basic protein (pI #1;11). MS analysis showed that SPC4 consists of two glycoforms with molecular masses of 34227 and 35629 Da and it contains a type-b heme. Chemical deglycosylation allowed to estimate sugar contents of 3.0% and 6.7% (w ⁄ w) in glycoform I and II, respectively, and a mass of the apoprotein of 33 246 Da. High performance anion exchange chromatography allowed to determine the carbohydrate constituents of the polysaccharide ...


Shrinkage Estimation For Sage Data Using A Mixture Dirichlet Prior, Jeffrey S. Morris, Keith A. Baggerly, Kevin R. Coombes Mar 2006

Shrinkage Estimation For Sage Data Using A Mixture Dirichlet Prior, Jeffrey S. Morris, Keith A. Baggerly, Kevin R. Coombes

Jeffrey S. Morris

Serial Analysis of Gene Expression (SAGE) is a technique for estimating the gene expression profile of a biological sample. Any efficient inference in SAGE must be based upon efficient estimates of these gene expression profiles, which consist of the estimated relative abundances for each mRNA species present in the sample. The data from SAGE experiments are counts for each observed mRNA species, and can be modeled using a multinomial distribution with two characteristics: skewness in the distribution of relative abundances and small sample size relative to the dimension. As a result of these characteristics, a given SAGE sample will fail ...


An Introduction To High-Throughput Bioinformatics Data, Keith A. Baggerly, Kevin R. Coombes, Jeffrey S. Morris Mar 2006

An Introduction To High-Throughput Bioinformatics Data, Keith A. Baggerly, Kevin R. Coombes, Jeffrey S. Morris

Jeffrey S. Morris

High throughput biological assays supply thousands of measurements per sample, and the sheer amount of related data increases the need for better models to enhance inference. Such models, however, are more effective if they take into account the idiosyncracies associated with the specific methods of measurement: where the numbers come from. We illustrate this point by describing three different measurement platforms: microarrays, serial analysis of gene expression (SAGE), and proteomic mass spectrometry.


Bayesian Mixture Models For Gene Expression And Protein Profiles, Michele Guindani, Kim-Anh Do, Peter Mueller, Jeffrey S. Morris Mar 2006

Bayesian Mixture Models For Gene Expression And Protein Profiles, Michele Guindani, Kim-Anh Do, Peter Mueller, Jeffrey S. Morris

Jeffrey S. Morris

We review the use of semi-parametric mixture models for Bayesian inference in high throughput genomic data. We discuss three specific approaches for microarray data, for protein mass spectrometry experiments, and for SAGE data. For the microarray data and the protein mass spectrometry we assume group comparison experiments, i.e., experiments that seek to identify genes and proteins that are differentially expressed across two biologic conditions of interest. For the SAGE data example we consider inference for a single biologic sample.


Analysis Of Mass Spectrometry Data Using Bayesian Wavelet-Based Functional Mixed Models, Jeffrey S. Morris, Philip J. Brown, Keith A. Baggerly, Kevin R. Coombes Mar 2006

Analysis Of Mass Spectrometry Data Using Bayesian Wavelet-Based Functional Mixed Models, Jeffrey S. Morris, Philip J. Brown, Keith A. Baggerly, Kevin R. Coombes

Jeffrey S. Morris

In this chapter, we demonstrate how to analyze MALDI-TOF/SELDITOF mass spectrometry data using the wavelet-based functional mixed model introduced by Morris and Carroll (2006), which generalizes the linear mixed models to the case of functional data. This approach models each spectrum as a function, and is very general, accommodating a broad class of experimental designs and allowing one to model nonparametric functional effects for various factors, which can be conditions of interest (e.g. cancer/normal) or experimental factors (blocking factors). Inference on these functional effects allows us to identify protein peaks related to various outcomes of interest, including ...


The Importance Of Maltose In Transitory Starch Breakdown, Yan Lu, Thomas Sharkey Feb 2006

The Importance Of Maltose In Transitory Starch Breakdown, Yan Lu, Thomas Sharkey

Yan Lu

No abstract provided.


Dna Damage Responses In Progeroid Syndromes Arise From Defective Maturation Of Prelamin A, Michael Sinensky, Y. Liu, A. Rusinol, Y. Wang, Y. Zou Jan 2006

Dna Damage Responses In Progeroid Syndromes Arise From Defective Maturation Of Prelamin A, Michael Sinensky, Y. Liu, A. Rusinol, Y. Wang, Y. Zou

Michael Sinensky

The genetic diseases Hutchinson-Gilford progeria syndrome (HGPS) and restrictive dermopathy (RD) arise from accumulation of farnesylated prelamin A because of defects in the lamin A maturation pathway. Both of these diseases exhibit symptoms that can be viewed as accelerated aging. The mechanism by which accumulation of farnesylated prelamin A leads to these accelerated aging phenotypes is not understood. Here we present evidence that in HGPS and RD fibroblasts, DNA damage checkpoints are persistently activated because of the compromise in genomic integrity. Inactivation of checkpoint kinases Ataxia-telangiectasia-mutated (ATM) and ATR (ATM- and Rad3-related) in these patient cells can partially overcome their ...


Farnesylated Lamins, Progeroid Syndromes And Farnesyl Transferase Inhibitors, Michael Sinensky, A. E. Rusinol Jan 2006

Farnesylated Lamins, Progeroid Syndromes And Farnesyl Transferase Inhibitors, Michael Sinensky, A. E. Rusinol

Michael Sinensky

Three mammalian nuclear lamin proteins, lamin B1, lamin B2 and the lamin A precursor, prelamin A, undergo canonical farnesylation and processing at CAAX motifs. In the case of prelamin A, there is an additional farnesylation-dependent endoproteolysis, which is defective in two congenital diseases: Hutchinson-Gilford progeria (HGPS) and restrictive dermopathy (RD). These two diseases arise respectively from defects in the prelamin A substrate and the enzyme (ZmpSte24) that processes it. Recent work has shed light on the roles of the lamin proteins and the enzymes involved in their farnesylation-dependent maturation. Other experimental work, including mouse model studies, have examined the possibility ...


The Role Of Arp2/3 And Scar/Wave Complexes In Polar Growth Of The Apical Cell Of The Moss Physcomitrella, Rs Quatrano, Pf Perroud, P Harries, M Bezanilla, Ah Pan, P Klueh, D Cove Jan 2006

The Role Of Arp2/3 And Scar/Wave Complexes In Polar Growth Of The Apical Cell Of The Moss Physcomitrella, Rs Quatrano, Pf Perroud, P Harries, M Bezanilla, Ah Pan, P Klueh, D Cove

Magdalena Bezanilla

No abstract provided.


Synergistic Mitogenic Signaling Of The Tobacco Specific Carcinogen, 4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanone (Nnk) And Ethanol On Immortalized Human Pancreatic Duct Epithelial Cells, Mdf Askari, Ms Tsao, Maria Cekanova, Hildegard Schuller Dec 2005

Synergistic Mitogenic Signaling Of The Tobacco Specific Carcinogen, 4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanone (Nnk) And Ethanol On Immortalized Human Pancreatic Duct Epithelial Cells, Mdf Askari, Ms Tsao, Maria Cekanova, Hildegard Schuller

Maria Cekanova MS, RNDr, PhD

No abstract provided.


A Simple Atomic Force Microscopy Method The Visualization Of Polar And Non-Polar Parts Organic Films, A.A. Yu, P.R. Stoney, J.E. Norvillez, M. Vaughn, E.J. Pascial, Barry Bruce, M. Baldo, F. Stellacci Dec 2005

A Simple Atomic Force Microscopy Method The Visualization Of Polar And Non-Polar Parts Organic Films, A.A. Yu, P.R. Stoney, J.E. Norvillez, M. Vaughn, E.J. Pascial, Barry Bruce, M. Baldo, F. Stellacci

Barry D. Bruce

Here we present a scanning probe microscopy method that allows for the identification of regions of different polarity (i.e. hydrophilicity) in thin organic films. This technique is based on the analysis of the difference between phase images generated at different applied bias voltages in tapping-mode atomic force microscopy. We show that, without any chemical modification of the microscope tip, it is possible to investigate surface properties of complex macromolecular layers, yielding new insight into the functional properties of the photosynthetic electron transport macromolecular complex, Photosystem I.


Cellular And Organ Level Localization Of Maltose In Maltose-Excess Arabidopsis Mutants, Yan Lu, Jon Steichen, Sean Weise, Thomas Sharkey Dec 2005

Cellular And Organ Level Localization Of Maltose In Maltose-Excess Arabidopsis Mutants, Yan Lu, Jon Steichen, Sean Weise, Thomas Sharkey

Yan Lu

No abstract provided.


The Role Of Cytosolic A-Glucan Phosphorylase In Maltose Metabolism And The Comparison Of Amylomaltose In Arabidopsis And E. Coli, Yan Lu, Jon Steichen, Jian Yao, Thomas Sharkey Dec 2005

The Role Of Cytosolic A-Glucan Phosphorylase In Maltose Metabolism And The Comparison Of Amylomaltose In Arabidopsis And E. Coli, Yan Lu, Jon Steichen, Jian Yao, Thomas Sharkey

Yan Lu

No abstract provided.


Identification Of Important Regions For Ethylene Binding And Signaling In The Transmembrane Domain Of The Etr1 Ethylene Receptor Of Arabidopsis, Brad Binder, Wuyi Wang, Jeff Esch, Shin-Han Shiu, Hasi Agula, Caren Chang, Sara Patterson, Anthony Bleecker Dec 2005

Identification Of Important Regions For Ethylene Binding And Signaling In The Transmembrane Domain Of The Etr1 Ethylene Receptor Of Arabidopsis, Brad Binder, Wuyi Wang, Jeff Esch, Shin-Han Shiu, Hasi Agula, Caren Chang, Sara Patterson, Anthony Bleecker

Brad M. Binder

The ethylene binding domain (EBD) of the Arabidopsis thaliana ETR1 receptor is modeled as three membrane-spanning helices. We surveyed ethylene binding activity in different kingdoms and performed a bioinformatic analysis of the EBD. Ethylene binding is confined to land plants, Chara, and a group of cyanobacteria but is largely absent in other organisms, consistent with our finding that EBD-like sequences are overrepresented among plant and cyanobacterial species. We made amino acid substitutions in 37 partially or completely conserved residues of the EBD and assayed their effects on ethylene binding and signaling. Mutations primarily in residues in Helices I and II ...


Interfacial Properties And Structural Conformation Of Thermosonicated Bovice Serum Albumin, D. Guzey, I. Gulseren, Barry Bruce, J. Weiss Dec 2005

Interfacial Properties And Structural Conformation Of Thermosonicated Bovice Serum Albumin, D. Guzey, I. Gulseren, Barry Bruce, J. Weiss

Barry D. Bruce

Aqueous Bovine Serum Albumin (BSA) solutions were treated with high-intensity ultrasound (20 W cm−2) for 15, 30 and 45 min at temperatures of up to 85 °C. The equilibrium and dynamic surface tension of native and ultrasonicated BSA at the air-solution interface was measured using drop shape analysis. The effect of ultrasound on the secondary structure of BSA was monitored by circular dichroism spectroscopy. Surface pressure of BSA at the air-solvent interface increased as a consequence of sonication treatment at 20 °C. Both the rate of surface pressure increase and the equilibrium surface pressure of sonicated BSA were significantly ...


Soluble Fibrin Inhibits Monocyte Adherence And Cytotoxicity Against Tumor Cells: Implications For Cancer Metastasis, John Biggerstaff, Brandy Weidow, Jacqueline Vidosh, Judith Dexheimer, Shonak Patel, Pretesh Patel Dec 2005

Soluble Fibrin Inhibits Monocyte Adherence And Cytotoxicity Against Tumor Cells: Implications For Cancer Metastasis, John Biggerstaff, Brandy Weidow, Jacqueline Vidosh, Judith Dexheimer, Shonak Patel, Pretesh Patel

John Biggerstaff

Background Soluble fibrin (sFn) is a marker for disseminated intravascular coagulation and may have prognostic significance, especially in metastasis. However, a role for sFn in the etiology of metastatic cancer growth has not been extensively studied. We have reported that sFn cross-linked platelet binding to tumor cells via the major platelet fibrin receptor αIIbβ3, and tumor cell CD54 (ICAM-1), which is the receptor for two of the leukocyte β2 integrins (αLβ2 and aMβ2). We hypothesized that sFn may also affect leukocyte adherence, recognition, and killing of tumor cells. Furthermore, in a rat experimental metastasis model sFn pre-treatment of tumor cells ...