Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

University of Massachusetts Medical School

Cellular and Molecular Physiology

Keyword
Publication Year
Publication
Publication Type
File Type

Articles 421 - 443 of 443

Full-Text Articles in Life Sciences

A Genetically Encoded Fluorescent Sensor Of Erk Activity, Christopher D. Harvey, Anka G. Ehrhardt, Cristina Arrigo Cellurale, Haining Zhong, Ryohei Yasuda, Roger J. Davis, Karel Svoboda Dec 2008

A Genetically Encoded Fluorescent Sensor Of Erk Activity, Christopher D. Harvey, Anka G. Ehrhardt, Cristina Arrigo Cellurale, Haining Zhong, Ryohei Yasuda, Roger J. Davis, Karel Svoboda

Davis Lab Publications

The activity of the ERK has complex spatial and temporal dynamics that are important for the specificity of downstream effects. However, current biochemical techniques do not allow for the measurement of ERK signaling with fine spatiotemporal resolution. We developed a genetically encoded, FRET-based sensor of ERK activity (the extracellular signal-regulated kinase activity reporter, EKAR), optimized for signal-to-noise ratio and fluorescence lifetime imaging. EKAR selectively and reversibly reported ERK activation in HEK293 cells after epidermal growth factor stimulation. EKAR signals were correlated with ERK phosphorylation, required ERK activity, and did not report the activities of JNK or p38. EKAR reported ERK ...


Percutaneous Transendocardial Delivery Of Self-Complementary Adeno-Associated Virus 6 Achieves Global Cardiac Gene Transfer In Canines, Lawrence T. Bish, Meg M. Sleeper, Benjamin Brainard, Stephen Cole, Nicholas Russell, Elanor Withnall, Jason Arndt, Caryn Reynolds, Ellen Davison, Julio Sanmiguel, Di Wu, Guangping Gao, James M. Wilson, H Lee Sweeney Dec 2008

Percutaneous Transendocardial Delivery Of Self-Complementary Adeno-Associated Virus 6 Achieves Global Cardiac Gene Transfer In Canines, Lawrence T. Bish, Meg M. Sleeper, Benjamin Brainard, Stephen Cole, Nicholas Russell, Elanor Withnall, Jason Arndt, Caryn Reynolds, Ellen Davison, Julio Sanmiguel, Di Wu, Guangping Gao, James M. Wilson, H Lee Sweeney

Open Access Articles

Achieving efficient cardiac gene transfer in a large animal model has proven to be technically challenging. Previous strategies have used cardiopulmonary bypass or dual catheterization with the aid of vasodilators to deliver vectors, such as adenovirus, adeno-associated virus (AAV), or plasmid DNA. Although single-stranded AAV (ssAAV) vectors have shown the greatest promise, they suffer from delayed expression, which might be circumvented using self-complementary vectors. We sought to optimize cardiac gene transfer using a percutaneous transendocardial injection catheter to deliver adeno-associated viral vectors to the canine myocardium. Four vectors were evaluated-ssAAV9, self-complementary AAV9 (scAAV9), scAAV8, scAAV6-so that comparison could be made ...


Jun N-Terminal Kinase 1 Regulates Epithelial-To-Mesenchymal Transition Induced By Tgf-Beta1, John F. Alcorn, Amy S. Guala, Jos Van Der Velden, Brian Mcelhinney, Charles G. Irvin, Roger J. Davis, Yvonne M.W. Janssen-Heininger Apr 2008

Jun N-Terminal Kinase 1 Regulates Epithelial-To-Mesenchymal Transition Induced By Tgf-Beta1, John F. Alcorn, Amy S. Guala, Jos Van Der Velden, Brian Mcelhinney, Charles G. Irvin, Roger J. Davis, Yvonne M.W. Janssen-Heininger

Davis Lab Publications

Transforming growth factor beta1 (TGF-beta1) is a cardinal cytokine in the pathogenesis of airway remodeling, and promotes epithelial-to-mesenchymal transition (EMT). As a molecular interaction between TGF-beta1 and Jun N-terminal kinase (JNK) has been demonstrated, the goal of this study was to elucidate whether JNK plays a role in TGF-beta1-induced EMT. Primary cultures of mouse tracheal epithelial cells (MTEC) from wild-type, JNK1-/- or JNK2-/- mice were comparatively evaluated for their ability to undergo EMT in response to TGF-beta1. Wild-type MTEC exposed to TGF-beta1 demonstrated a prominent induction of mesenchymal mediators and a loss of epithelial markers, in conjunction with a loss ...


C-Jun Nh2-Terminal Kinase 2 Inhibits Gamma Interferon Production During Anaplasma Phagocytophilum Infection, Joao H.F. Pedra, Jochen Mattner, Jian Tao, Steven M. Kerfoot, Roger J. Davis, Richard A. Flavell, Philip W. Askenase, Zhinan Yin, Erol Fikrig Jan 2008

C-Jun Nh2-Terminal Kinase 2 Inhibits Gamma Interferon Production During Anaplasma Phagocytophilum Infection, Joao H.F. Pedra, Jochen Mattner, Jian Tao, Steven M. Kerfoot, Roger J. Davis, Richard A. Flavell, Philip W. Askenase, Zhinan Yin, Erol Fikrig

Davis Lab Publications

Gamma interferon (IFN-gamma) plays a critical role in the early eradication of Anaplasma phagocytophilum. However, the mechanisms that regulate IFN-gamma production upon infection remain poorly understood. Here we show that c-Jun NH2-terminal kinase 2 (JNK2) inhibits IFN-gamma production during A. phagocytophilum infection. jnk2-null mice were more refractory to infection with A. phagocytophilum and produced increased levels of IFN-gamma after challenge with the pathogen. The resistance of jnk2-null mice to A. phagocytophilum infection was due to elevated levels of IFN-gamma secreted by conventional and natural killer (NK) T cells. The administration of alpha-galactosylceramide, a strong NK T-cell agonist, increased IFN-gamma release ...


Suppression Of P53-Dependent Senescence By The Jnk Signal Transduction Pathway, Madhumita Das, Feng Jiang, Hayla Karen Sluss, Chao Zhang, Kevan M. Shokat, Richard A. Flavell, Roger J. Davis Oct 2007

Suppression Of P53-Dependent Senescence By The Jnk Signal Transduction Pathway, Madhumita Das, Feng Jiang, Hayla Karen Sluss, Chao Zhang, Kevan M. Shokat, Richard A. Flavell, Roger J. Davis

Open Access Articles

The JNK signaling pathway is implicated in the regulation of the AP1 transcription factor and cell proliferation. Here, we examine the role of JNK by using conditional and chemical genetic alleles of the ubiquitously expressed murine genes that encode the isoforms JNK1 and JNK2. Our analysis demonstrates that JNK is not essential for proliferation. However, JNK is required for expression of the cJun and JunD components of the AP1 transcription factor, and JNK-deficient cells exhibit early p53-dependent senescence. These data demonstrate that JNK can act as a negative regulator of the p53 tumor suppressor.


C-Jun N-Terminal Kinase 1 Is Required For Toll-Like Receptor 1 Gene Expression In Macrophages, Hooman Izadi, Amirreza T. Motameni, Tonya C. Bates, Elias R. Olivera, Vega Villar-Suarez, Ila Joshi, Renu Garg, Barbara A. Osborne, Roger J. Davis, Mercedes Rincon, Juan Anguita Oct 2007

C-Jun N-Terminal Kinase 1 Is Required For Toll-Like Receptor 1 Gene Expression In Macrophages, Hooman Izadi, Amirreza T. Motameni, Tonya C. Bates, Elias R. Olivera, Vega Villar-Suarez, Ila Joshi, Renu Garg, Barbara A. Osborne, Roger J. Davis, Mercedes Rincon, Juan Anguita

Davis Lab Publications

The regulation of innate immune responses to pathogens occurs through the interaction of Toll-like receptors (TLRs) with pathogen-associated molecular patterns and the activation of several signaling pathways whose contribution to the overall innate immune response to pathogens is poorly understood. We demonstrate a mechanism of control of murine macrophage responses mediated by TLR1/2 heterodimers through c-Jun N-terminal kinase 1 (JNK1) activity. JNK controls tumor necrosis factor alpha production and TLR-mediated macrophage responses to Borrelia burgdorferi, the causative agent of Lyme disease, and the TLR1/TLR2-specific agonist PAM(3)CSK(4). JNK1, but not JNK2, activity regulates the expression of ...


Requirement Of Jip Scaffold Proteins For Nmda-Mediated Signal Transduction, Norman J. Kennedy, Gilles Martin, Anka G. Ehrhardt, Julie Cavanagh-Kyros, Chia-Yi Kuan, Pasko Rakic, Richard A. Flavell, Steven N. Treistman, Roger J. Davis Sep 2007

Requirement Of Jip Scaffold Proteins For Nmda-Mediated Signal Transduction, Norman J. Kennedy, Gilles Martin, Anka G. Ehrhardt, Julie Cavanagh-Kyros, Chia-Yi Kuan, Pasko Rakic, Richard A. Flavell, Steven N. Treistman, Roger J. Davis

Davis Lab Publications

JIP scaffold proteins are implicated in the regulation of protein kinase signal transduction pathways. To test the physiological role of these scaffold proteins, we examined the phenotype of compound mutant mice that lack expression of JIP proteins. These mice were found to exhibit severe defects in N-methyl-D-aspartic acid (NMDA) receptor function, including decreased NMDA-evoked current amplitude, cytoplasmic Ca(++), and gene expression. The decreased NMDA receptor activity in JIP-deficient neurons is associated with reduced tyrosine phosphorylation of NR2 subunits of the NMDA receptor. JIP complexes interact with the SH2 domain of cFyn and may therefore promote tyrosine phosphorylation and activity of ...


Structural Insights Into The Interaction Of The Evolutionarily Conserved Zpr1 Domain Tandem With Eukaryotic Ef1a, Receptors, And Smn Complexes, Ashwini K. Mishra, Laxman Gangwani, Roger J. Davis, David G. Lambright Aug 2007

Structural Insights Into The Interaction Of The Evolutionarily Conserved Zpr1 Domain Tandem With Eukaryotic Ef1a, Receptors, And Smn Complexes, Ashwini K. Mishra, Laxman Gangwani, Roger J. Davis, David G. Lambright

Open Access Articles

Eukaryotic genomes encode a zinc finger protein (ZPR1) with tandem ZPR1 domains. In response to growth stimuli, ZPR1 assembles into complexes with eukaryotic translation elongation factor 1A (eEF1A) and the survival motor neurons protein. To gain insight into the structural mechanisms underlying the essential function of ZPR1 in diverse organisms, we determined the crystal structure of a ZPR1 domain tandem and characterized the interaction with eEF1A. The ZPR1 domain consists of an elongation initiation factor 2-like zinc finger and a double-stranded beta helix with a helical hairpin insertion. ZPR1 binds preferentially to GDP-bound eEF1A but does not directly influence the ...


Data From: Ptc124 Targets Genetic Disorders Caused By Nonsense Mutations, Allan Jacobson, Phyllis Spatrick, Feng He May 2007

Data From: Ptc124 Targets Genetic Disorders Caused By Nonsense Mutations, Allan Jacobson, Phyllis Spatrick, Feng He

MaPS Research Data

Manuscript abstract: Nonsense mutations promote premature translational termination and cause anywhere from 5-70% of the individual cases of most inherited diseases. Studies on nonsense-mediated cystic fibrosis have indicated that boosting specific protein synthesis from less than 1% to as little as 5% of normal levels may greatly reduce the severity or eliminate the principal manifestations of disease. To address the need for a drug capable of suppressing premature termination, we identified PTC124-a new chemical entity that selectively induces ribosomal readthrough of premature but not normal termination codons. PTC124 activity, optimized using nonsense-containing reporters, promoted dystrophin production in primary muscle cells ...


Dihydropyridine Receptors And Type 1 Ryanodine Receptors Constitute The Molecular Machinery For Voltage-Induced Ca2+ Release In Nerve Terminals, Valerie De Crescenzo, Kevin E. Fogarty, Ronghua Zhuge, Richard A. Tuft, Lawrence M. Lifshitz, Jeffrey Carmichael, Karl D. Bellve, Stephen P. Baker, Spyros Zissimopoulos, F. Anthony Lai, Jose R. Lemos, John V. Walsh Jr. Jul 2006

Dihydropyridine Receptors And Type 1 Ryanodine Receptors Constitute The Molecular Machinery For Voltage-Induced Ca2+ Release In Nerve Terminals, Valerie De Crescenzo, Kevin E. Fogarty, Ronghua Zhuge, Richard A. Tuft, Lawrence M. Lifshitz, Jeffrey Carmichael, Karl D. Bellve, Stephen P. Baker, Spyros Zissimopoulos, F. Anthony Lai, Jose R. Lemos, John V. Walsh Jr.

Information Technology Publications and Presentations

Ca2+ stores were studied in a preparation of freshly dissociated terminals from hypothalamic magnocellular neurons. Depolarization from a holding level of -80 mV in the absence of extracellular Ca2+ elicited Ca2+ release from intraterminal stores, a ryanodine-sensitive process designated as voltage-induced Ca2+ release (VICaR). The release took one of two forms: an increase in the frequency but not the quantal size of Ca2+ syntillas, which are brief, focal Ca2+ transients, or an increase in global [Ca2+]. The present study provides evidence that the sensors of membrane potential for VICaR are dihydropyridine receptors (DHPRs). First, over the range of -80 to ...


The Frequency Of Calcium Oscillations Induced By 5-Ht, Ach, And Kcl Determine The Contraction Of Smooth Muscle Cells Of Intrapulmonary Bronchioles, Jose F. Perez, Michael J. Sanderson Jun 2005

The Frequency Of Calcium Oscillations Induced By 5-Ht, Ach, And Kcl Determine The Contraction Of Smooth Muscle Cells Of Intrapulmonary Bronchioles, Jose F. Perez, Michael J. Sanderson

Open Access Articles

Increased resistance of airways or blood vessels within the lung is associated with asthma or pulmonary hypertension and results from contraction of smooth muscle cells (SMCs). To study the mechanisms regulating these contractions, we developed a mouse lung slice preparation containing bronchioles and arterioles and used phase-contrast and confocal microscopy to correlate the contractile responses with changes in [Ca(2+)](i) of the SMCs. The airways are the focus of this study. The agonists, 5-hydroxytrypamine (5-HT) and acetylcholine (ACH) induced a concentration-dependent contraction of the airways. High concentrations of KCl induced twitching of the airway SMCs but had little effect ...


Intraflagellar Transport And Cilia-Dependent Renal Disease: The Ciliary Hypothesis Of Polycystic Kidney Disease, Gregory J. Pazour Oct 2004

Intraflagellar Transport And Cilia-Dependent Renal Disease: The Ciliary Hypothesis Of Polycystic Kidney Disease, Gregory J. Pazour

Open Access Articles

Epithelial cells that line mammalian kidney nephrons have solitary nonmotile primary cilium projecting from their surface into the lumens of the ducts and tubules. Mutations that block the assembly of these cilia cause cystic kidney disease. The products of human autosomal dominant and recessive polycystic kidney disease genes and products of the nephronophthisis disease genes are at least partially localized to primary cilia. This suggests that the cilium serves as an organizing center for the early steps of the signal transduction pathway that is responsible for monitoring the integrity of the kidney nephron and controlling cell proliferation and differentiation.


Fc-Receptor-Mediated Phagocytosis Is Regulated By Mechanical Properties Of The Target, Karen A. Beningo, Yu-Li Wang Feb 2002

Fc-Receptor-Mediated Phagocytosis Is Regulated By Mechanical Properties Of The Target, Karen A. Beningo, Yu-Li Wang

Open Access Articles

Phagocytosis is an actin-based process used by macrophages to clear particles greater than 0.5 microm in diameter. In addition to its role in immunological responses, phagocytosis is also necessary for tissue remodeling and repair. To prevent catastrophic autoimmune reactions, phagocytosis must be tightly regulated. It is commonly assumed that the recognition/selection of phagocytic targets is based solely upon receptor-ligand binding. Here we report an important new criterion, that mechanical parameters of the target can dramatically affect the efficiency of phagocytosis. When presented with particles of identical chemical properties but different rigidity, macrophages showed a strong preference to engulf ...


The Role Of Tnf-Receptor Family Members And Other Traf-Dependent Receptors In Bone Resorption, Ellen M. Gravallese, Deborah L. Galson, Steven R. Goldring, Philip E. Auron Feb 2001

The Role Of Tnf-Receptor Family Members And Other Traf-Dependent Receptors In Bone Resorption, Ellen M. Gravallese, Deborah L. Galson, Steven R. Goldring, Philip E. Auron

Rheumatology Publications and Presentations

The contribution of osteoclasts to the process of bone loss in inflammatory arthritis has recently been demonstrated. Studies in osteoclast biology have led to the identification of factors responsible for the differentiation and activation of osteoclasts, the most important of which is the receptor activator of NF-kappa B ligand/osteoclast differentiation factor (RANKL/ODF), a tumor necrosis factor (TNF)-like protein. The RANKL/ODF receptor, receptor activator of NF-kappa B (RANK), is a TNF-receptor family member present on both osteoclast precursors and mature osteoclasts. Like other TNF-family receptors and the IL-1 receptor, RANK mediates its signal transduction via TNF receptor-associated ...


The Nuclear Factor Of Activated T Cells (Nfat) Transcription Factor Nfatp (Nfatc2) Is A Repressor Of Chondrogenesis, Ann M. Ranger, Louis C. Gerstenfeld, Jinxi Wang, Tamiyo Kon, Hyunsu Bae, Ellen M. Gravallese, Melvin J. Glimcher, Laurie H. Glimcher Jan 2000

The Nuclear Factor Of Activated T Cells (Nfat) Transcription Factor Nfatp (Nfatc2) Is A Repressor Of Chondrogenesis, Ann M. Ranger, Louis C. Gerstenfeld, Jinxi Wang, Tamiyo Kon, Hyunsu Bae, Ellen M. Gravallese, Melvin J. Glimcher, Laurie H. Glimcher

Rheumatology Publications and Presentations

Nuclear factor of activated T cells (NFAT) transcription factors regulate gene expression in lymphocytes and control cardiac valve formation. Here, we report that NFATp regulates chondrogenesis in the adult animal. In mice lacking NFATp, resident cells in the extraarticular connective tissues spontaneously differentiate to cartilage. These cartilage cells progressively differentiate and the tissue undergoes endochondral ossification, recapitulating the development of endochondral bone. Proliferation of already existing articular cartilage cells also occurs in some older animals. At both sites, neoplastic changes in the cartilage cells occur. Consistent with these data, NFATp expression is regulated in mesenchymal stem cells induced to differentiate ...


A Novel Membrane Protein Influencing Cell Shape And Multicellular Swarming Of Proteus Mirabilis, Nicole A. Hay, Donald J. Tipper, Daniel Gygi, Colin Hughes Apr 1999

A Novel Membrane Protein Influencing Cell Shape And Multicellular Swarming Of Proteus Mirabilis, Nicole A. Hay, Donald J. Tipper, Daniel Gygi, Colin Hughes

Microbiology and Physiological Systems Publications and Presentations

Swarming in Proteus mirabilis is characterized by the coordinated surface migration of multicellular rafts of highly elongated, hyperflagellated swarm cells. We describe a transposon mutant, MNS185, that was unable to swarm even though vegetative cells retained normal motility and the ability to differentiate into swarm cells. However, these elongated cells were irregularly curved and had variable diameters, suggesting that the migration defect results from the inability of these deformed swarm cells to align into multicellular rafts. The transposon was inserted at codon 196 of a 228-codon gene that lacks recognizable homologs. Multiple copies of the wild-type gene, called ccmA, for ...


A Nonswarming Mutant Of Proteus Mirabilis Lacks The Lrp Global Transcriptional Regulator, Nicole A. Hay, Donald J. Tipper, Daniel Gygi, Colin Hughes Aug 1997

A Nonswarming Mutant Of Proteus Mirabilis Lacks The Lrp Global Transcriptional Regulator, Nicole A. Hay, Donald J. Tipper, Daniel Gygi, Colin Hughes

Microbiology and Physiological Systems Publications and Presentations

Proteus swarming is the rapid cyclical population migration across surfaces by elongated cells that hyperexpress flagellar and virulence genes. The mini-Tn5 transposon mutant mns2 was isolated as a tight nonswarming mutant that did not elongate or upregulate flagellar and hemolysin genes. Individual cell motility was retained but was reduced. The transposon had inserted in the gene encoding the global transcriptional regulator Lrp (leucine-responsive regulatory protein), expression of which was upregulated in differentiating swarm cells. Swarming was restored to the lrp mutant by artificial overexpression of the flhDC flagellar regulatory master operon. Lrp may be a key component in generating or ...


Signal Transduction Mechanisms For The Stimulation Of Lipolysis By Growth Hormone: A Dissertation, Rupert G. Yip Aug 1994

Signal Transduction Mechanisms For The Stimulation Of Lipolysis By Growth Hormone: A Dissertation, Rupert G. Yip

GSBS Dissertations and Theses

The purpose of this study was to investigate the mechanism of action of lipolysis by growth hormone in rat adipocytes. GH-induced lipolysis, in contrast to that of isoproterenol (ISO), is slow in onset (lag time >1h), small in magnitude (~2X basal). and requires corticosteroid. Evidence for direct coupling between GH receptors and adenylyl cyclase or G-proteins is lacking, and although we could detect no measurable change in cAMP content after treatment with GH + dexamethasone (Dex), it is likely that cAMP activation of protein kinase A is a central event in GH-induced lipolysis. Rp-cAMPS, a competitive antagonist of cAMP was equally ...


Poly(A) Rna Codistribution With Microfilaments: Evaluation By In Situ Hybridization And Quantitative Digital Imaging Microscopy, Krishan L. Taneja, Lawrence M. Lifshitz, Fredric S. Fay, Robert H. Singer Dec 1992

Poly(A) Rna Codistribution With Microfilaments: Evaluation By In Situ Hybridization And Quantitative Digital Imaging Microscopy, Krishan L. Taneja, Lawrence M. Lifshitz, Fredric S. Fay, Robert H. Singer

Open Access Articles

The distribution of poly(A) RNA has been visualized in single cells using high-resolution fluorescent in situ hybridization. Digital imaging microscopy was used to quantitate the signal in various cellular compartments. Most of the poly(A) signal remained associated with the cellular filament systems after solubilization of membranes with Triton, dissociation of ribosomes with puromycin, and digestion of non-poly(A) RNA with ribonuclease A and T1. The actin filaments were shown to be the predominant cellular structural elements associating with the poly(A) because low doses of cytochalasin released about two-thirds of the poly(A). An approach to assess the ...


A Lipopolysaccharide-Induced Dna-Binding Protein For A Class Ii Gene In B Cells Is Distinct From Nf-Kappa B, Ellen M. Gravallese, Mark R. Boothby, Cynthia M. Smas, Laurie H. Glimcher Aug 1989

A Lipopolysaccharide-Induced Dna-Binding Protein For A Class Ii Gene In B Cells Is Distinct From Nf-Kappa B, Ellen M. Gravallese, Mark R. Boothby, Cynthia M. Smas, Laurie H. Glimcher

Rheumatology Publications and Presentations

Class II (Ia) major histocompatibility complex molecules are cell surface proteins normally expressed by a limited subset of cells of the immune system. These molecules regulate the activation of T cells and are required for the presentation of antigens and the initiation of immune responses. The expression of Ia in B cells is determined by both the developmental stage of the B cell and by certain external stimuli. It has been demonstrated previously that treatment of B cells with lipopolysaccharide (LPS) results in increased surface expression of Ia protein. However, we have confirmed that LPS treatment results in a significant ...


Secretion Of Saccharomyces Cerevisiae Killer Toxin: Processing Of The Glycosylated Precursor, H. Bussey, D. Saville, D. Greene, Donald J. Tipper, Keith A. Bostian Aug 1983

Secretion Of Saccharomyces Cerevisiae Killer Toxin: Processing Of The Glycosylated Precursor, H. Bussey, D. Saville, D. Greene, Donald J. Tipper, Keith A. Bostian

Microbiology and Physiological Systems Publications and Presentations

Killer toxin secretion was blocked at the restrictive temperature in Saccharomyces cerevisiae sec mutants with conditional defects in the S. cerevisiae secretory pathway leading to accumulation of endoplasmic reticulum (sec18), Golgi (sec7), or secretory vesicles (sec1). A 43,000-molecular-weight (43K) glycosylated protoxin was found by pulse-labeling in all sec mutants at the restrictive temperature. In sec18 the protoxin was stable after a chase; but in sec7 and sec1 the protoxin was unstable, and in sec1 11K toxin was detected in cell lysates. The chymotrypsin inhibitor tosyl-l-phenylalanyl chloromethyl ketone (TPCK) blocked toxin secretion in vivo in wild-type cells by inhibiting protoxin ...


Coat Protein Synthesis During Sporulation Of Bacillus Subtilis: Immunological Detection Of Soluble Precursors To The 12,200-Dalton Spore Coat Protein, Robert C. Goldman, Donald J. Tipper Sep 1981

Coat Protein Synthesis During Sporulation Of Bacillus Subtilis: Immunological Detection Of Soluble Precursors To The 12,200-Dalton Spore Coat Protein, Robert C. Goldman, Donald J. Tipper

Microbiology and Physiological Systems Publications and Presentations

Antibody specific to the 12,200-dalton spore coat protein of Bacillus subtilis was used to detect the synthesis of cross-reacting material during sporulation. Cross-reacting protein was first detected by immunoprecipitation after 4 h of development and represented at least 1 to 2% of the total soluble protein synthesis at 5.5 h. A polypeptide of 21,000 daltons was detected in immunoprecipitates by gel electrophoresis. This polypeptide did not accumulate in sporulating cells and was rapidly turned over at the time of coat deposition. In contrast, a 32,000-dalton polypeptide reacted with antibody when unlabeled cell protein was denatured with ...


Nonenzymatic Glycosylation Of Erythrocyte Membrane Proteins. Relevance To Diabetes, J A. Miller, Ellen M. Gravallese, H F. Bunn Apr 1980

Nonenzymatic Glycosylation Of Erythrocyte Membrane Proteins. Relevance To Diabetes, J A. Miller, Ellen M. Gravallese, H F. Bunn

Rheumatology Publications and Presentations

Nonenzymatic glycosylation of proteins of the erythrocyte membrane was determined by incubating erythrocyte ghosts with [3H]borohydride. The incorporation of tritium into protein provides a reliable assay of ketoamine linkages. The membrane proteins from 18 patients with diabetes incorporated twice as much radioactivity as membrane proteins from normal erythrocytes. After acid hydrolysis, amino acid analysis showed that the majority of radioactivity was localized to glucosyllysine. Autoradiograms showed that all of the major proteins of the erythrocyte membrane, separated by electrophoresis on sodium dodecyl sulfate gels, contained ketoamine linkages. No protein bands in either normal or diabetic erythrocytes showed significant preferential ...