A5032610249- Ionosphere and magnetosphere dynamics
- Geophysics and Gravity Measurements
- Methane Hydrates and Related Phenomena
- Monoclonal and Polyclonal Antibodies Research
- Solar and Space Plasma Dynamics
- HER2/EGFR in Cancer Research
- Glycosylation and Glycoproteins Research
- Bioinformatics and Genomic Networks
- Astrophysics and Cosmic Phenomena
- Cellular transport and secretion
- Receptor Mechanisms and Signaling
- Gene Regulatory Network Analysis
- Genetics, Bioinformatics, and Biomedical Research
- Cell Adhesion Molecules Research
- Advanced Proteomics Techniques and Applications
- Protein Kinase Regulation and GTPase Signaling
- Seismic Waves and Analysis
- Computational Drug Discovery Methods
- Lipid Membrane Structure and Behavior
- Cellular Mechanics and Interactions
- Reproductive biology and impacts on aquatic species
- Gene expression and cancer classification
- Earthquake Detection and Analysis
- Health and Medical Research Impacts
- Advanced Fluorescence Microscopy Techniques
Environmental Molecular Sciences Laboratory
2015-2024
Pacific Northwest National Laboratory
2015-2024
National Institutes of Health
1979-2012
National Eye Institute
2012
BOKU University
2012
Battelle
2005-2011
University of Glasgow
2008
Oak Ridge National Laboratory
1978-2008
University of Tennessee at Knoxville
1978-2008
Clemson University
2007
Deregulation of signaling by the epidermal growth factor receptor (EGFR) is common in human malignancy progression. One mutant EGFR (variously named ΔEGFR, de2-7 EGFR, or EGFRvIII), which occurs frequently cancers, lacks a portion extracellular ligand-binding domain due to genomic deletions that eliminate exons 2 7 and confers dramatic enhancement brain tumor cell tumorigenicity <i>in vivo</i>. In order dissect molecular mechanisms this activity, we analyzed location, autophosphorylation,...
ABSTRACT Human cytomegalovirus (HCMV), a member of the herpesvirus family, is large complex enveloped virus composed both viral and cellular gene products. While sequence HCMV genome has been known for over decade, full set proteins that compose virion are unknown. To approach this problem we have utilized gel-free two-dimensional capillary liquid chromatography-tandem mass spectrometry (MS/MS) Fourier transform ion cyclotron resonance MS to identify determine relative abundances in purified...
Identification of a mutant epidermal growth factor (EGF) receptor that does not undergo downregulation has provided genetic probe to investigate the role internalization in ligand-induced mitogenesis. Contact-inhibited cells expressing this internalization-defective exhibited normal mitogenic response at significantly lower ligand concentrations than did wild-type receptors. A transformed phenotype and anchorage-independent were observed failed elicit these responses These findings imply...
of endocytosis have been mainly restricted to the qualitative level (6-9).We recently presented a set steady state equations that accurately describe cellular binding, internalization, and degradation polypeptide ligands under physiological conditions (5).A central concept in our model is endocytotic rate constant ( k , ) which we defined as probability an occupied receptor being internalized 1 min at 37 "C.The ligand-receptor k, important because its value ' The abbreviations used are:...
The principles governing acquisition and interspecies exchange of nutrients in microbial communities how those exchanges impact community productivity are poorly understood. Here, we examine energy macronutrient unicyanobacterial consortia for which species-resolved genome information exists all members, allowing us to use multi-omic approaches predict species' abilities acquire resources expression resource-acquisition genes during succession. Metabolic reconstruction indicated that a...
Ligand activation of the epidermal growth factor receptor (EGFR) leads to its rapid internalization and eventual delivery lysosomes. This process is thought be a mechanism attenuate signaling, but signals could potentially generated after endocytosis. To directly evaluate EGFR signaling during trafficking, we developed technique rapidly selectively isolate internalized associated molecules with use reversibly biotinylated anti-EGFR antibodies. In addition, antibodies specific...
ErbB-2/HER2 is an important signaling partner for the epidermal growth factor receptor (EGFR). Overexpression of erbB-2 also associated with poor prognosis in breast cancer. To investigate how amplification affects its interactions EGFR, we used a human mammary epithelial cell system which expression was increased 7–20-fold by gene transfection. We found that caused constitutive activation as well ligand-independent EGFR. strongly inhibited down-regulation following transactivation...
Abstract Occupancy-induced down-regulation of cell surface epidermal growth factor (EGF) receptors attenuates signal transduction. To define mechanisms through which this class occurs, we have investigated the relative roles ligand-induced internalization and recycling in process. Occupied, kinase-active EGF were internalized a high affinity, saturable endocytic system at rates up to 10-fold faster than empty receptors. In contrast, full length lacking tyrosine kinase activity underwent rate...
Ligands that activate the epidermal growth factor receptor (EGFR) are synthesized as membrane-anchored precursors appear to be proteolytically released by members of ADAM family metalloproteases. Because EGFR ligands thought biologically active, role ligand release in regulation signaling is unclear. To investigate this question, we used metalloprotease inhibitors block from human mammary epithelial cells. These cells express both transforming α and amphiregulin require autocrine through for...
This study was conducted to determine how extraordinarily high numbers of epidermal growth factor receptors (EGF-R) affected the binding and internalization EGF in transformed cell line A431. I found that at low concentrations, kinetics behaved as a nonsaturable, first-order process showing no evidence multiple-affinity classes receptors. However, dissociation rates were strongly dependent on degree receptor occupancy both intact cells isolated membranes. occupancy-dependent appears be due...
We have developed a quantitative method to evaluate the interaction between cell surface receptors and endocytic apparatus. This exploits occupancy-dependent changes in internalization rates that occur cells expressing high numbers of receptors. found constitutive transferrin receptor behaves as simple, first order process is unaltered by ligand. Internalization epidermal growth factor (EGF) receptor, however, saturable, second induced occupancy. EGF occurs through at least two distinct...
Because mitogenic stimulation by epidermal growth factor (EGF) requires at least an 8-12-h exposure to commit the majority of cells divide, a number complicating processes must be evaluated in analysis relationship between receptor occupancy and biological response.During this period, cellular EGF receptors changes continuously bind, internalize, degrade hormone.To deal with these changes, we utilized our previously described steady state model that permits interactions under conditions.For...
Abstract Motivation: Modern transcriptomics and proteomics enable us to survey the expression of RNAs proteins at large scales. While these data are usually generated analyzed separately, there is an increasing interest in comparing co-analyzing transcriptome proteome data. A major open question whether linked how it coordinated. Results: Here we have developed a probabilistic clustering model that permits analysis links between transcriptomic proteomic profiles sensible flexible manner. Our...
Measurement precision determines the power of any analysis to reliably identify significant signals, such as in screens for differential expression, independent whether experimental design incorporates replicates or not. With compilation large-scale RNA-Seq datasets with technical replicate samples, however, we can now, first time, perform a systematic expression level estimates from massively parallel sequencing technology. This then allows considerations its improvement by computational...
Various genetic mutations associated with cancer are known to alter cell signaling, but it is not clear whether they dysregulate signaling pathways by altering the abundance of pathway proteins. Using a combination RNA sequencing and ultrasensitive targeted proteomics, we defined primary components-16 core proteins 10 feedback regulators-of epidermal growth factor receptor (EGFR)-mitogen-activated protein kinase (MAPK) in normal human mammary epithelial cells then quantified their absolute...
Targeted inhibition of oncogenic pathways can be highly effective in halting the rapid growth tumors but often leads to emergence slowly dividing persister cells, which constitute a reservoir for selection drug-resistant clones. In BRAFV600E melanomas, RAF and MEK inhibitors efficiently block signaling, cells emerge. Here, we show that escape drug-induced cell-cycle arrest via brief, sporadic ERK pulses generated by transmembrane receptors factors operating an autocrine/paracrine manner....
Abstract Large numbers of cells are generally required for quantitative global proteome profiling due to surface adsorption losses associated with sample processing. Such bulk measurement obscures important cell-to-cell variability (cell heterogeneity) and makes proteomic impossible rare cell populations (e.g., circulating tumor (CTCs)). Here we report a surfactant-assisted one-pot preparation coupled mass spectrometry (MS) method termed SOP-MS label-free single-cell proteomics. capitalizes...