Medical Biochemistry Commons^™

Androgen-Independent Prostate Cancer Cells Acquire The Complete Steroidogenic Potential Of Synthesizing Testosterone From Cholesterol., Paulette R. Dillard, Ming-Fong Lin, Shafiq A. Khan

Journal Articles: Biochemistry & Molecular Biology

The proliferation and differentiation of normal prostate epithelial cells depends upon the action of androgens produced by the testis. Prostate cancers retain the ability to respond to androgens in the initial stages of cancer development, but progressively become independent of exogenous androgens in advanced stages of the disease while maintaining the expression of functional androgen receptor (AR). In the present study, we have determined the potential of prostate cancer cells to synthesize androgens from cholesterol which may be involved in intracrine regulation of AR in advanced stages of the disease. Established androgen-independent prostate cancer cell lines, PC3 and DU145 cells, …

Deregulation Of Muc4 In Gastric Adenocarcinoma: Potential Pathobiological Implication In Poorly Differentiated Non-Signet Ring Cell Type Gastric Cancer., S. Senapati, P. Chaturvedi, P. Sharma, G Venkatraman, Jane L. Meza, W. El-Rifai, H. K. Roy, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

MUC4 is a large, heavily glycosylated transmembrane mucin, that is implicated in the pathogenesis of various types of cancers. To date, no extensive study has been done to check the expression and functional significance of MUC4 in different types of gastric adenocarcinomas. Here, we report the expression profile of MUC4 in gastric adenocarcinomas and its function in poorly differentiated gastric non-signet ring cell carcinoma (non-SRCC) type cells. Immunohistochemical analysis using tissue microarray (TMA) showed a significant difference in MUC4 expression between normal adjacent (n = 45) and gastric adenocarcinoma (n = 83; P < 0.001). MUC4 expression was not associated with tumour type, stage or with the degree of differentiation. To gain further insight into the significance of MUC4 expression in gastric non-SRCC cells, MUC4 was ectopically expressed in AGS, a poorly differentiated gastric non-signet ring cell line. The MUC4 overexpressing cells (AGS-MUC4) showed a significant increase (P < 0.005) in cell motility and a decrease in cellular aggregation as compared with the vector-transfected cells. Furthermore, in vivo tumorigenicity analysis revealed that animals transplanted with the MUC4 overexpressing cells (AGS-MUC4) had a greater incidence of tumours (83%) in comparison to empty vector control (17%). In addition, the expression of MUC4 resulted in enhanced expression of total cellular ErbB2 and phosphorylated ErbB2. In conclusion, our results showed that MUC4 is overexpressed in gastric adenocarcinoma tissues, and that it has a role in promoting aggressive properties in poorly differentiated gastric non-SRCC cells through the activation of the ErbB2 oncoprotein.

Mitochondrial Redox Signaling By P66shc Is Involved In Regulating Androgenic Growth Stimulation Of Human Prostate Cancer Cells., Suresh Veeramani, Ta-Chun Yuan, Fen-Fen Lin, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

p66Shc is shown to negatively regulate the life span in mice through reactive oxygen species (ROS) production. Recent reports, however, revealed that p66Shc protein level is significantly elevated in several human cancer tissues and growth-stimulated carcinoma cells, suggesting a mitogenic and carcinogenic role for p66Shc. In this communication, we demonstrate for the first time that p66Shc mediates androgenic growth signals in androgen-sensitive human prostate cancer cells through mitochondrial ROS production. Growth stimulation of prostate cancer cells with 5alpha-dihydrotestosterone (DHT) is accompanied by increased p66Shc level and ROS production, which is abolished by antioxidant treatments. However, antioxidant treatments do not affect …

Muc4 Activates Her2 Signalling And Enhances The Motility Of Human Ovarian Cancer Cells., Moorthy P. Ponnusamy, A. P. Singh, Maneesh Jain, S. Chakraborty, N. Moniaux, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

The mucin MUC4 is a high molecular weight transmembrane glycoprotein. It consists of a mucin-type subunit (MUC4alpha) and a transmembrane growth factor-like subunit (MUC4beta). The mucin MUC4 is overexpressed in many epithelial malignancies including ovarian cancer, suggesting a possible role in the pathogenesis of these cancers. In this study, we investigated the functional role of MUC4 in the human ovarian cancer cell line SKOV3. The mucin MUC4 was ectopically expressed by stable transfection, and its expression was examined by western blot and confocal microscopy analyses. The in vitro studies demonstrated an enhanced motility of MUC4-expressing SKOV3 cells compared with the …

Neutralization Of Botulinum Neurotoxin By A Human Monoclonal Antibody Specific For The Catalytic Light Chain., Sharad P Adekar, Tsuyoshi Takahashi, R Mark Jones, Fetweh H Al-Saleem, Denise M Ancharski, Michael J Root, B P Kapadnis, Lance L Simpson, Scott K Dessain

Department of Biochemistry and Molecular Biology Faculty Papers

BACKGROUND: Botulinum neurotoxins (BoNT) are a family of category A select bioterror agents and the most potent biological toxins known. Cloned antibody therapeutics hold considerable promise as BoNT therapeutics, but the therapeutic utility of antibodies that bind the BoNT light chain domain (LC), a metalloprotease that functions in the cytosol of cholinergic neurons, has not been thoroughly explored.

METHODS AND FINDINGS: We used an optimized hybridoma method to clone a fully human antibody specific for the LC of serotype A BoNT (BoNT/A). The 4LCA antibody demonstrated potent in vivo neutralization when administered alone and collaborated with an antibody specific for …

Muc4 And Muc5ac Are Highly Specific Tumour-Associated Mucins In Biliary Tract Cancer., W. R. Matull, F. Andreola, A. Loh, Z. Adiguzel, M. Deheragoda, U. Qureshi, Surinder K. Batra, D. M. Swallow, S. P. Pereira

Journal Articles: Biochemistry & Molecular Biology

Alterations in epithelial mucin expression are associated with carcinogenesis, but there are few data in biliary tract cancer (BTC). In pancreatic malignancy, MUC4 is a diagnostic and prognostic tumour marker, whereas MUC5AC has been proposed as a sensitive serological marker for BTC. We assessed MUC4 and MUC5AC expression in (i) prospectively collected bile and serum specimens from 72 patients with biliary obstruction (39 BTC) by real-time reverse transcriptase-PCR (qPCR) and western blot analysis, and (ii) 79 archived biliary tissues (69 BTC) by immunohistochemistry. In bile, MUC4 protein was detected in 27% of BTC and 29% of primary sclerosing cholangitis (PSC) …

Early Diagnosis Of Pancreatic Cancer: Neutrophil Gelatinase-Associated Lipocalin As A Marker Of Pancreatic Intraepithelial Neoplasia., N. Moniaux, S. Chakraborty, M. Yalniz, J. Gonzalez, Valerie K. Shostrom, J. Standop, Subodh M. Lele, Michel M. Ouellette, Parviz M. Pour, Aaron Sasson, R. E. Brand, Michael A. Hollingsworth, Maneesh Jain, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Pancreatic cancer is a highly lethal malignancy with a dismal 5-year survival of less than 5%. The scarcity of early biomarkers has considerably hindered our ability to launch preventive measures for this malignancy in a timely manner. Neutrophil gelatinase-associated lipocalin (NGAL), a 24-kDa glycoprotein, was reported to be upregulated nearly 27-fold in pancreatic cancer cells compared to normal ductal cells in a microarray analysis. Given the need for biomarkers in the early diagnosis of pancreatic cancer, we investigated the expression of NGAL in tissues with the objective of examining if NGAL immunostaining could be used to identify foci of pancreatic …

Abeta42 Mutants With Different Aggregation Profiles Induce Distinct Pathologies In Drosophila., Koichi Iijima, Hsueh-Cheng Chiang, Stephen A Hearn, Inessa Hakker, Anthony Gatt, Christopher Shenton, Linda Granger, Amy Leung, Kanae Iijima-Ando, Yi Zhong

Department of Biochemistry and Molecular Biology Faculty Papers

Aggregation of the amyloid-beta-42 (Abeta42) peptide in the brain parenchyma is a pathological hallmark of Alzheimer's disease (AD), and the prevention of Abeta aggregation has been proposed as a therapeutic intervention in AD. However, recent reports indicate that Abeta can form several different prefibrillar and fibrillar aggregates and that each aggregate may confer different pathogenic effects, suggesting that manipulation of Abeta42 aggregation may not only quantitatively but also qualitatively modify brain pathology. Here, we compare the pathogenicity of human Abeta42 mutants with differing tendencies to aggregate. We examined the aggregation-prone, EOFAD-related Arctic mutation (Abeta42Arc) and an artificial mutation (Abeta42art) that …

Genome-Wide Expression Profiling Reveals Transcriptomic Variation And Perturbed Gene Networks In Androgen-Dependent And Androgen-Independent Prostate Cancer Cells., Ajay P. Singh, Sangeeta Bafna, Kunal Chaudhary, Ganesh Venkatraman, Lynette Smith, James D. Eudy, Sonny L. Johansson, Ming-Fong Lin, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Previously, we have developed a unique in vitro LNCaP cell model, which includes androgen-dependent (LNCaP-C33), androgen-independent (LNCaP-C81) and an intermediate phenotype (LNCaP-C51) cell lines resembling the stages of prostate cancer progression to hormone independence. This model is advantageous in overcoming the heterogeneity associated with the prostate cancer up to a certain extent. We characterized and compared the gene expression profiles in LNCaP-C33 (androgen-dependent) and LNCaP-C81 (androgen-independent) cells using Affymetrix GeneChip array analyses. Multiple genes were identified exhibiting differential expression during androgen-independent progression. Among the important genes upregulated in androgen-independent cells were PCDH7, TPTE, TSPY, EPHA3, HGF, MET, EGF, TEM8, etc., …

Nicotinamide Riboside Kinase Structures Reveal New Pathways To Nad+, Wolfram Tempel, Wael M. Rabeh, Katrina L. Bogan, Peter Belenky, Marzena Wojcik, Heather F. Seidle, Lyudmila Nedyalkova, Tianle Yang, Anthony A. Sauve, Hee-Won Park, Charles Brenner

Dartmouth Scholarship

The eukaryotic nicotinamide riboside kinase (Nrk) pathway, which is induced in response to nerve damage and promotes replicative life span in yeast, converts nicotinamide riboside to nicotinamide adenine dinucleotide (NAD+) by phosphorylation and adenylylation. Crystal structures of human Nrk1 bound to nucleoside and nucleotide substrates and products revealed an enzyme structurally similar to Rossmann fold metabolite kinases and allowed the identification of active site residues, which were shown to be essential for human Nrk1 and Nrk2 activity in vivo. Although the structures account for the 500-fold discrimination between nicotinamide riboside and pyrimidine nucleosides, no enzyme feature was identified to recognize …

Recent Advances In Cancer Stem/Progenitor Cell Research: Therapeutic Implications For Overcoming Resistance To The Most Aggressive Cancers., M. Mimeault, Ralph Hauke, Parmender P. Mehta, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Overcoming intrinsic and acquired resistance of cancer stem/progenitor cells to current clinical treatments represents a major challenge in treating and curing the most aggressive and metastatic cancers. This review summarizes recent advances in our understanding of the cellular origin and molecular mechanisms at the basis of cancer initiation and progression as well as the heterogeneity of cancers arising from the malignant transformation of adult stem/progenitor cells. We describe the critical functions provided by several growth factor cascades, including epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), stem cell factor (SCF) receptor (KIT), hedgehog and Wnt/beta-catenin signalling pathways that …

Human Collagen Krox Up-Regulates Type I Collagen Expression In Normal And Scleroderma Fibroblasts Through Interaction With Sp1 And Sp3 Transcription Factors., Magdalini Kypriotou, Gallic Beauchef, Christos Chadjichristos, Russell Widom, Emmanuelle Renard, Sergio A. Jimenez, Joseph Korn, François-Xavier Maquart, Thierry Oddos, Otto Von Stetten, Jean-Pierre Pujol, Philippe Galéra

Department of Medicine Faculty Papers

Despite several investigations, the transcriptional mechanisms that regulate the expression of both type I collagen genes (COL1A1 and COL1A2) in either physiological or pathological situations, such as scleroderma, are not completely known. We have investigated the role of hc-Krox transcription factor on type I collagen expression by human dermal fibroblasts. hc-Krox exerted a stimulating effect on type I collagen protein synthesis and enhanced the corresponding mRNA steady-state levels of COL1A1 and COL1A2 in foreskin fibroblasts (FF), adult normal fibroblasts (ANF), and scleroderma fibroblasts (SF). Forced hc-Krox expression was found to up-regulate COL1A1 transcription through a -112/-61-bp sequence in FF, ANF, …

Human Muc4 Mucin Induces Ultra-Structural Changes And Tumorigenicity In Pancreatic Cancer Cells., N. Moniaux, P. Chaturvedi, G. C. Varshney, Jane L. Meza, J. F. Rodriguez-Sierra, J-P Aubert, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

MUC4 is a type-1 transmembrane glycoprotein and is overexpressed in many carcinomas. It is a heterodimeric protein of 930 kDa, composed of a mucin-type subunit, MUC4alpha, and a membrane-bound growth factor-like subunit, MUC4beta. MUC4 mRNA contains unique 5' and 3' coding sequences along with a large variable number of tandem repeat (VNTR) domain of 7-19 kb. A direct association of MUC4 overexpression has been established with the degree of invasiveness and poor prognosis of pancreatic cancer. To understand the precise role of MUC4 in pancreatic cancer, we engineered a MUC4 complementary DNA construct, mini-MUC4, whose deduced protein (320 kDa) is …

The Notch Regulator Maml1 Interacts With P53 And Functions As A Coactivator., Yongtong Zhao, Rebecca B. Katzman, Laurie M. Delmolino, Ishfaq Bhat, Ying Zhang, Channabasavaiah B. Gurumurthy, Aleksandra Germaniuk-Kurowska, Honey V. Reddi, Aharon Solomon, Mu-Sheng Zeng, Aisha Kung, Hui Ma, Qingshen Gao, Goberdhan Dimri, Adina Stanculescu, Lucio Miele, Lizi Wu, James D. Griffin, David E. Wazer, Hamid Band, Vimla Band

Journal Articles: Biochemistry & Molecular Biology

Members of the evolutionarily conserved Mastermind (MAM) protein family, including the three related mammalian Mastermind-like (MAML) proteins MAML1-3, function as crucial coactivators of Notch-mediated transcriptional activation. Given the recent evidence of cross-talk between the p53 and Notch signal transduction pathways, we have investigated whether MAML1 may also be a transcriptional coactivator of p53. Indeed, we show here that MAML1 is able to interact with p53. We show that MAML1-p53 interaction involves the N-terminal region of MAML1 and the DNA-binding domain of p53, and we use a chromatin immunoprecipitation assay to show that MAML1 is part of the activator complex that …

An Essential Role Of Human Ada3 In P53 Acetylation., Alo Nag, Aleksandra Germaniuk-Kurowska, Manjari Dimri, Michael A. Sassack, Channabasavaiah B. Gurumurthy, Qingshen Gao, Goberdhan Dimri, Hamid Band, Vimla Band

Journal Articles: Biochemistry & Molecular Biology

The p53 tumor suppressor protein functions as a critical component of genotoxic stress response by regulating the expression of effector gene products that control the fate of a cell following DNA damage. Unstressed cells maintain p53 at low levels through regulated degradation, and p53 levels and activity are rapidly elevated upon genotoxic stress. Biochemical mechanisms that control the levels and activity of p53 are therefore of great interest. We and others have recently identified hAda3 (human homologue of yeast alteration/deficiency in activation 3) as a p53-interacting protein and enhancer of p53 activity. Here, we show that endogenous levels of p53 …

Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta

Journal Articles: Biochemistry & Molecular Biology

The constituent proteins of gap junctions, called connexins (Cxs), have a short half-life. Despite this, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation have remained poorly understood. We show here that in androgen-responsive human prostate cancer cells, androgens control the expression level of Cx32-and hence the extent of gap junction formation-post-translationally. In the absence of androgens, a major fraction of Cx32 is degraded presumably by endoplasmic reticulum-associated degradation, whereas in their presence, this fraction is rescued from degradation. We also show that Cx32 and Cx43 degrade by a similar mechanism. Thus, androgens regulate …

Characterization Of Hard2, A Processed Hard1 Gene Duplicate, Encoding A Human Protein N-Alpha-Acetyltransferase., Thomas Arnesen, Matthew J Betts, Frédéric Pendino, David A Liberles, Dave Anderson, Jaime Caro, Xianguo Kong, Jan E Varhaug, Johan R Lillehaug

Department of Medicine Faculty Papers

BACKGROUND: Protein acetylation is increasingly recognized as an important mechanism regulating a variety of cellular functions. Several human protein acetyltransferases have been characterized, most of them catalyzing epsilon-acetylation of histones and transcription factors. We recently described the human protein acetyltransferase hARD1 (human Arrest Defective 1). hARD1 interacts with NATH (N-Acetyl Transferase Human) forming a complex expressing protein N-terminal alpha-acetylation activity. RESULTS: We here describe a human protein, hARD2, with 81 % sequence identity to hARD1. The gene encoding hARD2 most likely originates from a eutherian mammal specific retrotransposition event. hARD2 mRNA and protein are expressed in several human cell lines. …

The Human Paf Complex Coordinates Transcription With Events Downstream Of Rna Synthesis., Bing Zhu, Subhrangsu S. Mandal, Anh-Dung Pham, Yong Zheng, Hediye Erdjument-Bromage, Surinder K. Batra, Paul Tempst, Danny Reinberg

Journal Articles: Biochemistry & Molecular Biology

The yeast PAF (yPAF) complex interacts with RNA polymerase II and coordinates the setting of histone marks associated with active transcription. We report the isolation and functional characterization of the human PAF (hPAF) complex. hPAF shares four subunits with yPAF (hCtr9, hPaf1, hLeo1, and hCdc73), but contains a novel higher eukaryotic-specific subunit, hSki8. RNAi against hSki8 or hCtr9 reduces the cellular levels of other hPAF subunits and of mono- and trimethylated H3-Lys 4 and dimethylated H3-Lys 79. The hSki8 subunit is also a component of the human SKI (hSKI) complex. Yeast SKI complex is cytoplasmic and together with Exosome mediates …

Multiple Roles Of Mucins In Pancreatic Cancer, A Lethal And Challenging Malignancy., N. Moniaux, M. Andrianifahanana, R. E. Brand, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Mucins are members of an expanding family of large multifunctional glycoproteins. Pancreatic mucins have important biological functions, including the protection, lubrication, and moisturisation of the surfaces of epithelial tissues lining ductal structures within the pancreas. Several lines of evidence support the notion that deregulated mucin production is a hallmark of inflammatory and neoplastic disorders of the pancreas. Herein, we discuss the factors that contribute to the lethality of pancreatic cancer as well as the key role played by mucins, particularly MUC1 and MUC4, in the development and progression of the disease. Aspects pertaining to the aberrant expression and glycosylation of …

Binding Between The Niemann–Pick C1 Protein And A Photoactivatable Cholesterol Analog Requires A Functional Sterol-Sensing Domain, Nobutaka Ohgami, Dennis C. Ko, Matthew Thomas, Matthew P. Scott, Catherine C. Y. Chang, Ta-Yuan Chang

Dartmouth Scholarship

Niemann-Pick type C (NPC) 1 protein plays important roles in moving cholesterol and other lipids out of late endosomes by means of vesicular trafficking, but it is not known whether NPC1 directly interacts with cholesterol. We performed photoaffinity labeling of intact cells expressing fluorescent protein (FP)-tagged NPC1 by using [(3)H]7,7-azocholestanol ([(3)H]AC). After immunoprecipitation, (3)H-labeled NPC1-GFP appeared as a single band. Including excess unlabeled sterol to the labeling reaction significantly diminished the labeling. Altering the NPC1 sterol-sensing domain (SSD) with loss-of-function mutations (P692S and Y635C) severely reduced the extent of labeling. To further demonstrate the specificity of labeling, we show that …

Transcriptional Activation Of The Human Prostatic Acid Phosphatase Gene By Nf-Kappab Via A Novel Hexanucleotide-Binding Site., Stanislav Zelivianski, Richard Glowacki, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

Human prostatic acid phosphatase (PAcP) is a prostate epithelium-specific differentiation antigen. Cellular PAcP functions as a neutral protein tyrosine phosphatase and is involved in regulating androgen-promoted prostate cancer cell proliferation. Despite the fact that the promoter of the PAcP gene has been cloned, the transcriptional factors that regulate PAcP expression remain unidentified. This article describes our analyses of the promoter of the PAcP gene. Deletion analyses of the promoter sequence up to -4893 (-4893/+87) revealed that a 577 bp fragment (-1356/-779) represents the unique positive cis-active element in human prostate cancer cells but not in HeLa cervix carcinoma cells. Interestingly, …

The Tumor Suppressor Lkb1 Kinase Directly Activates Amp-Activated Kinase And Regulates Apoptosis In Response To Energy Stress, Reuben J. Shaw, Monica Kosmatka, Nabeel Bardeesy, Rebecca L. Hurley, Lee A. Witters, Ronald A. Depinho, Lewis C. Cantley

Dartmouth Scholarship

AMP-activated protein kinase (AMPK) is a highly conserved sensor of cellular energy status found in all eukaryotic cells. AMPK is activated by stimuli that increase the cellular AMP/ATP ratio. Essential to activation of AMPK is its phosphorylation at Thr-172 by an upstream kinase, AMPKK, whose identity in mammalian cells has remained elusive. Here we present biochemical and genetic evidence indicating that the LKB1 serine/threonine kinase, the gene inactivated in the Peutz-Jeghers familial cancer syndrome, is the dominant regulator of AMPK activation in several mammalian cell types. We show that LKB1 directly phosphorylates Thr-172 of AMPKalpha in vitro and activates its …

Muc4 Mucin Expression In Human Pancreatic Tumours Is Affected By Organ Environment: The Possible Role Of Tgfbeta2., A. Choudhury, N. Moniaux, A. B. Ulrich, B. M. Schmied, J. Standop, Parviz M. Pour, S. J. Gendler, Michael A. Hollingsworth, J-P Aubert, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

MUC4 is highly expressed in human pancreatic tumours and pancreatic tumour cell lines, but is minimally or not expressed in normal pancreas or chronic pancreatitis. Here, we investigated the aberrant regulation of MUC4 expression in vivo using clonal human pancreatic tumour cells (CD18/HPAF) grown either orthotopically in the pancreas (OT) or ectopically in subcutaneous tissue (SC) in the nude mice. Histological examination of the OT and SC tumours showed moderately differentiated and anaplastic morphology, respectively. The OT tumour cells showed metastases to distant lymph nodes and faster tumour growth (P

Copper Chelation Represses The Vascular Response To Injury, Lazar Mandinov, Anna Mandinova, Stanimir Kyurkchiev, Dobroslav Kyurkchiev, Ivan Kehayov, Vihren Kolev, Raffaella Soldi, Cinzia Bagala, Ebo D. De Muinck, Volkhard Lindner, Mark J. Post, Michael Simons

Dartmouth Scholarship

The induction of an acute inflammatory response followed by the release of polypeptide cytokines and growth factors from peripheral blood monocytes has been implicated in mediating the response to vascular injury. Because the Cu2+-binding proteins IL-1alpha and fibroblast growth factor 1 are exported into the extracellular compartment in a stress-dependent manner by using intracellular Cu2+ to facilitate the formation of S100A13 heterotetrameric complexes and these signal peptideless polypeptides have been implicated as regulators of vascular injury in vivo, we examined the ability of Cu2+ chelation to repress neointimal thickening in response to injury. We observed that the oral administration of …

Mammalian Erv46 Localizes To The Endoplasmic Reticulum–Golgi Intermediate Compartment And To Cis-Golgi Cisternae, Lelio Orci, Mariella Ravazzola, Gary J. Mack, Charles Barlowe, Stefan Otte

Dartmouth Scholarship

Yeast endoplasmic reticulum (ER) vesicle protein Erv46p is a novel membrane protein involved in transport through the early secretory pathway. Investigation of mammalian Erv46 (mErv46) reveals that it is broadly expressed in tissues and protein-secreting cells. By immunofluorescence microscopy, mErv46 displays a crescent-shaped perinuclear staining pattern that is characteristic of the Golgi complex. Quantitative immunoelectron microscopy indicates that mErv46 is restricted to the cis face of the Golgi apparatus and to vesicular tubular structures between the transitional ER and cis-Golgi. Minor amounts of mErv46 reside in ER membranes and later Golgi cisternae. On Brefeldin A treatment, mErv46 redistributes to punctate …

Transfection Of Il-10 Expression Vectors Into Endothelial Cultures Attenuates Alpha4beta7-Dependent Lymphocyte Adhesion Mediated By Madcam-1., Makoto Sasaki, Paul Jordan, Jeff Houghton, Xianmin Meng, Makoto Itoh, Takashi Joh, J Steven Alexander

Department of Dermatology and Cutaneous Biology Faculty Papers

BACKGROUND: Enhanced expression of MAdCAM-1 (mucosal addressin cell adhesion molecule-1) is associated with the onset and progression of inflammatory bowel disease. The clinical significance of elevated MAdCAM-1 expression is supported by studies showing that immunoneutralization of MAdCAM-1, or its ligands reduce inflammation and mucosal damage in models of colitis. Interleukin-10 (IL-10) is an endogenous anti-inflammatory and immunomodulatory cytokine that has been shown to prevent inflammation and injury in several animal studies, however clinical IL-10 treatment remains insufficient because of difficulties in the route of IL-10 administration and its biological half-life. Here, we examined the ability of introducing an IL-10 expression …

Analysis Of Mitotic Microtubule-Associated Proteins Using Mass Spectrometry Identifies Astrin, A Spindle-Associated Protein, Gary J. Mack, Duane A. Compton

Dartmouth Scholarship

We purified microtubules from a mammalian mitotic extract and obtained an amino acid sequence from each microtubule-associated protein by using mass spectrometry. Most of these proteins are known spindle-associated components with essential functional roles in spindle organization. We generated antibodies against a protein identified in this collection and refer to it as astrin because of its association with astral microtubule arrays assembled in vitro. Astrin is approximately 134 kDa, and except for a large predicted coiled-coil domain in its C-terminal region it lacks any known functional motifs. Astrin associates with spindle microtubules as early as prophase where it concentrates at …

The Chromokinesin Kid Is Necessary For Chromosome Arm Orientation And Oscillation, But Not Congression, On Mitotic Spindles, Aime A. Levesque, Duane A. Compton

Dartmouth Scholarship

Chromokinesins have been postulated to provide the polar ejection force needed for chromosome congression during mitosis. We have evaluated that possibility by monitoring chromosome movement in vertebrate-cultured cells using time-lapse differential interference contrast microscopy after microinjection with antibodies specific for the chromokinesin Kid. 17.5% of cells injected with Kid-specific antibodies have one or more chromosomes that remain closely opposed to a spindle pole and fail to enter anaphase. In contrast, 82.5% of injected cells align chromosomes in metaphase, progress to anaphase, and display chromosome velocities not significantly different from control cells. However, injected cells lack chromosome oscillations, and chromosome orientation …

Expression Of Tumor-Associated Glycoprotein-72 (Tag-72) Antigen In Human Prostatic Adenocarcinomas., Dev Karan, Sonny L. Johansson, Ming-Fong Lin, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Tumor-specific antigens are usually defined by monoclonal antibodies (MAbs) and can play critical roles in the diagnosis and therapy of carcinomas. Despite advances in the understanding of the molecular genetics of human prostate carcinomas, therapeutic approaches require that tumor-specific markers, preferably on the cell surface, should be defined. In this study, we examined the expression of an oncofetal antigen tumor-associated glycoprotein-72 (TAG-72) in prostatic adenocarcinomas with a Gleason grade of six or higher. Using a second generation MAb CC49 against TAG-72, immunoreactivity was detected in 88% (29/33) of the prostatic cancer tissues. Occasionally, the benign epithelium showed a very faint …

Anti-Human Immunodeficiency Virus (Hiv) Activities Of Halogenated Gomisin J Derivatives, New Nonnucleoside Inhibitors Of Hiv Type 1 Reverse Transcriptase, Toshiaki Fujihashi, Hiroto Hara, Toshiya Sakata, Kazuya Mori, Hirotaka Higuchi, Akio Tanaka, Hideko Kaji, Akira Kaji

Department of Biochemistry and Molecular Biology Faculty Papers

Halogenated gomisin J (a derivative of lignan compound), represented by the bromine derivative 1506 [(6R, 7S, S-biar)-4,9-dibromo-3,10-dihydroxy-1,2,11,12-tetramethoxy-6, 7-dimethyl-5,6,7,8- tetrahydrodibenzo[a,c]cyclo-octene], was found to be a potent inhibitor of the cytopathic effects of human immunodeficiency virus type 1 (HIV-1) on MT-4 human T cells (50% effective dose, 0.1 to 0.5 microM). Gomisin J derivatives were active in preventing p24 production from acutely HIV-1-infected H9 cells. The selective indices (toxic dose/effective dose) of these compounds were as high as > 300 in some systems. 1506 was active against 3'-azido-3'-deoxythymidine-resistant HIV-1 and acted synergistically with AZT and 2',3'-ddC. 1506 inhibited HIV-1 reverse transcriptase (RT) in …