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Articles 271 - 300 of 372

Full-Text Articles in Medical Biochemistry

Structural Insights Into Initial And Intermediate Steps Of The Ribosome-Recycling Process, Takeshi Yokoyama, Tanvir R. Shaikh, Nobuhiro Iwakura, Hideko Kaji, Akira Kaji, Rajendra K. Agrawal Mar 2012

Structural Insights Into Initial And Intermediate Steps Of The Ribosome-Recycling Process, Takeshi Yokoyama, Tanvir R. Shaikh, Nobuhiro Iwakura, Hideko Kaji, Akira Kaji, Rajendra K. Agrawal

Department of Biochemistry and Molecular Biology Faculty Papers

The ribosome recycling factor (RRF) and elongation factor G (EF-G) disassemble the 70S post-termination complex (PoTC) into mRNA, tRNA, and two ribosomal subunits. We have determined cryo-EM structures of the PoTC•RRF complex, with and without EF-G. We find that domain II of RRF initially interacts with universally conserved residues of the 23S rRNA helices 43 and 95, and protein L11 within the 50S ribosomal subunit. Upon EF-G binding, both RRF and tRNA are driven toward the tRNA-exit (E) site, with a large rotational movement of domain II of RRF toward the 30S ribosomal subunit. During this intermediate step of the …


Pathobiological Implications Of The Expression Of Egfr, Pakt, Nf-Κb And Mic-1 In Prostate Cancer Stem Cells And Their Progenies., Murielle Mimeault, Sonny L. Johansson, Surinder K. Batra Feb 2012

Pathobiological Implications Of The Expression Of Egfr, Pakt, Nf-Κb And Mic-1 In Prostate Cancer Stem Cells And Their Progenies., Murielle Mimeault, Sonny L. Johansson, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

The progression of prostate cancers (PCs) to locally invasive, androgen-independent and metastatic disease states is generally associated with treatment resistance and disease relapse. The present study was undertaken to establish the possibility of using a combination of specific oncogenic products, including epidermal growth factor receptor (EGFR), pAkt, nuclear factor-kappaB (NF-κB) and macrophage inhibitory cytokine-1 (MIC-1) as biomarkers and therapeutic targets for optimizing the management of patients with localized PC at earlier disease stages. The immunohistochemical and immunofluorescence data have revealed that the expression levels of EGFR, Ser(473)-pAkt, NF-κB p65 and MIC-1 proteins were significantly enhanced in the same subset of …


Regulation Of A Duplicated Locus: Drosophila Sloppy Paired Is Replete With Functionally Overlapping Enhancers., Miki Fujioka, James B Jaynes Feb 2012

Regulation Of A Duplicated Locus: Drosophila Sloppy Paired Is Replete With Functionally Overlapping Enhancers., Miki Fujioka, James B Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

In order to investigate regulation and redundancy within the sloppy paired (slp) locus, we analyzed 30 kilobases of DNA encompassing the tandem, coordinately regulated slp1 and slp2 transcription units. We found a remarkable array of stripe enhancers with overlapping activities surrounding the slp1 transcription unit, and, unexpectedly, glial cell enhancers surrounding slp2. The slp stripe regulatory region generates 7 stripes at blastoderm, and later 14 stripes that persist throughout embryogenesis. Phylogenetic analysis among drosophilids suggests that the multiplicity of stripe enhancers did not evolve through recent duplication. Most of the direct integration among cis-regulatory modules appears to be simply additive, …


Mir-25 Targets Tnf-Related Apoptosis Inducing Ligand (Trail) Death Receptor-4 And Promotes Apoptosis Resistance In Cholangiocarcinoma., Nataliya Razumilava, Steve F. Bronk, Rory L. Smoot, Christian D. Fingas, Nathan W. Werneburg, Lewis R. Roberts, Justin L. Mott Feb 2012

Mir-25 Targets Tnf-Related Apoptosis Inducing Ligand (Trail) Death Receptor-4 And Promotes Apoptosis Resistance In Cholangiocarcinoma., Nataliya Razumilava, Steve F. Bronk, Rory L. Smoot, Christian D. Fingas, Nathan W. Werneburg, Lewis R. Roberts, Justin L. Mott

Journal Articles: Biochemistry & Molecular Biology

It has been established that microRNA expression and function contribute to phenotypic features of malignant cells, including resistance to apoptosis. Although targets and functional roles for a number of microRNAs have been described in cholangiocarcinoma, many additional microRNAs dysregulated in this tumor have not been assigned functional roles. In this study, we identify elevated miR-25 expression in malignant cholangiocarcinoma cell lines as well as patient samples. In cultured cells, treatment with the Smoothened inhibitor, cyclopamine, reduced miR-25 expression, suggesting Hedgehog signaling stimulates miR-25 production. Functionally, miR-25 was shown to protect cells against TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. Correspondingly, antagonism of …


The Use Of Cerium Oxide And Curcumin Nanoparticles As Therapeutic Agents For The Treatment Of Ventricular Hypertrophy Following Pulmonary Arterial Hypertension, Madhukar Babu Kolli Jan 2012

The Use Of Cerium Oxide And Curcumin Nanoparticles As Therapeutic Agents For The Treatment Of Ventricular Hypertrophy Following Pulmonary Arterial Hypertension, Madhukar Babu Kolli

Theses, Dissertations and Capstones

Pulmonary arterial hypertension (PAH) is a progressive and fatal disease characterized by inflammation, increased pulmonary vascular resistance, right ventricular failure and premature death. Monocrotaline (MCT) has been used to induce PAH in laboratory rats. Previous in vitro and in vivo work suggested that cerium oxide (CeO2)-and curcumin nanoparticles exhibit anti-inflammatory activity; however, it is unknown if these materials are effective for the treatment of PAH induced cardiac hypertrophy. To determine the efficacy of CeO2 nanoparticle treatment in preventing MCT-induced RV hypertrophy, male Sprague Dawley rats were divided into one of three groups (control, MCT, or MCT + CeO2 nanoparticle, n=6/group). …


Mitochondrial Lysyl-Trna Synthetase Independent Import Of Trna Lysine Into Yeast Mitochondria., Naresh Babu V Sepuri, Madhavi Gorla, Michael P King Jan 2012

Mitochondrial Lysyl-Trna Synthetase Independent Import Of Trna Lysine Into Yeast Mitochondria., Naresh Babu V Sepuri, Madhavi Gorla, Michael P King

Department of Biochemistry and Molecular Biology Faculty Papers

Aminoacyl tRNA synthetases play a central role in protein synthesis by charging tRNAs with amino acids. Yeast mitochondrial lysyl tRNA synthetase (Msk1), in addition to the aminoacylation of mitochondrial tRNA, also functions as a chaperone to facilitate the import of cytosolic lysyl tRNA. In this report, we show that human mitochondrial Kars (lysyl tRNA synthetase) can complement the growth defect associated with the loss of yeast Msk1 and can additionally facilitate the in vitro import of tRNA into mitochondria. Surprisingly, the import of lysyl tRNA can occur independent of Msk1 in vivo. This suggests that an alternative mechanism is present …


Proteasome Regulation Of Caspase-8: Significance In Cancer, Michael Vincent Fiandalo Jan 2012

Proteasome Regulation Of Caspase-8: Significance In Cancer, Michael Vincent Fiandalo

Theses and Dissertations--Molecular and Cellular Biochemistry

Anti-tumor therapeutic strategies based on combinations of chemotherapeutic agents with a death inducing ligand such as TNF-α Related Apoptosis Inducing Ligand (TRAIL), are directed towards selective and effective cancer cell apoptosis and enhanced therapeutic response. We previously demonstrated that proteasome inhibition sensitizes TRAIL resistant prostate cancer cells to TRAIL-mediated apoptosis via stabilization of the active p18 subunit of initiator caspase-8. The present study investigated the functional link between caspase-8 and the proteasome, by analyzing the impact of caspase-8 ubiquitination and proteasomal degradation on the outcomes of the extrinsic apoptosis pathway in cancer cells. Caspase-8 ubiquitination status was assessed by polyubiquitin …


Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry Jan 2012

Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Evidence from multiple animal models demonstrates that testosterone plays a crucial role in the progression of symptoms in spinal and bulbar muscular atrophy (SBMA), a condition that results in neurodegeneration and muscle atrophy in affected men. Mice bearing a transgene encoding a human androgen receptor (AR) that contains a stretch of 112 glutamines (expanded polyglutamine tract; AR112Q mice) reproduce several aspects of the human disease. We treated transgenic male AR112Q mice with testosterone for 6 months. Surprisingly, testosterone treatment of AR112Q males did not exacerbate the disease. Although transgenic AR112Q males exhibited functional deficits when compared with non-transgenics, long-term testosterone …


Synergetic Effect Of Recoverin And Calmodulin On Regulation Of Rhodopsin Kinase., Ilya I Grigoriev, Ivan I Senin, Natalya K Tikhomirova, Konstantin E Komolov, Sergei E Permyakov, Evgeni Yu Zernii, Karl-Wilhelm Koch, Pavel P Philippov Jan 2012

Synergetic Effect Of Recoverin And Calmodulin On Regulation Of Rhodopsin Kinase., Ilya I Grigoriev, Ivan I Senin, Natalya K Tikhomirova, Konstantin E Komolov, Sergei E Permyakov, Evgeni Yu Zernii, Karl-Wilhelm Koch, Pavel P Philippov

Department of Biochemistry and Molecular Biology Faculty Papers

Phosphorylation of photoactivated rhodopsin by rhodopsin kinase (RK or GRK1), a first step of the phototransduction cascade turnoff, is under the control of Ca(2+)/recoverin. Here, we demonstrate that calmodulin, a ubiquitous Ca(2+)-sensor, can inhibit RK, though less effectively than recoverin does. We have utilized the surface plasmon resonance technology to map the calmodulin binding site in the RK molecule. Calmodulin does not interact with the recoverin-binding site within amino acid residues M1-S25 of the enzyme. Instead, the high affinity calmodulin binding site is localized within a stretch of amino acid residues V150-K175 in the N-terminal regulatory region of RK. Moreover, …


Histone Deacetylase Inhibitor Valproic Acid Suppresses The Growth And Increases The Androgen Responsiveness Of Prostate Cancer Cells., Yu-Wei Chou, Nagendra K. Chaturvedi, Shougiang Ouyang, Fen-Fen Lin, Dharam Kaushik, Jue Wang, Isaac Kim, Ming-Fong Lin Dec 2011

Histone Deacetylase Inhibitor Valproic Acid Suppresses The Growth And Increases The Androgen Responsiveness Of Prostate Cancer Cells., Yu-Wei Chou, Nagendra K. Chaturvedi, Shougiang Ouyang, Fen-Fen Lin, Dharam Kaushik, Jue Wang, Isaac Kim, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

We identified the molecular target by histone deacetylase (HDAC) inhibitors for exploring their potential prostate cancer (PCa) therapy. Upon HDAC inhibitors-treatment, LNCaP cell growth was suppressed, correlating with increased cellular prostatic acid phosphatase (cPAcP) expression, an authentic protein tyrosine phosphatase. In those cells, ErbB-2 was dephosphorylated, histone H3/H4 acetylation and methylation increased and cyclin proteins decreased. In PAcP shRNA-transfected C-81 cells, valproic acid (VPA) efficacy of growth suppression was diminished. Further, VPA pre-treatment enhanced androgen responsiveness of C-81, C4-2 and MDA PCa2b-AI cells. Thus, cPAcP expression is involved in growth suppression by HDAC inhibitors in PCa cells, and VPA pre-treatments …


Death Receptor 5 Signaling Promotes Hepatocyte Lipoapoptosis., Sophie C. Cazanave, Justin L. Mott, Steven F. Bronk, Nathan W. Werneburg, Christian D. Fingas, X Wei Meng, Niklas Finnberg, Wafik S. El-Deiry, Scott H. Kaufmann, Gregory J. Gores Nov 2011

Death Receptor 5 Signaling Promotes Hepatocyte Lipoapoptosis., Sophie C. Cazanave, Justin L. Mott, Steven F. Bronk, Nathan W. Werneburg, Christian D. Fingas, X Wei Meng, Niklas Finnberg, Wafik S. El-Deiry, Scott H. Kaufmann, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

Nonalcoholic steatohepatitis is characterized by hepatic steatosis, elevated levels of circulating free fatty acids (FFA), endoplasmic reticulum (ER) stress, and hepatocyte lipoapoptosis. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptor 5 (DR5) is significantly elevated in patients with nonalcoholic steatohepatitis, and steatotic hepatocytes demonstrate increased sensitivity to TRAIL-mediated cell death. Nonetheless, a role for TRAIL and/or DR5 in mediating lipoapoptotic pathways is unexplored. Here, we examined the contribution of DR5 death signaling to lipoapoptosis by free fatty acids. The toxic saturated free fatty acid palmitate induces an increase in DR5 mRNA and protein expression in Huh-7 human hepatoma cells leading …


The Raf/Mek/Extracellular Signal-Regulated Kinase 1/2 Pathway Can Mediate Growth Inhibitory And Differentiation Signaling Via Androgen Receptor Downregulation In Prostate Cancer Cells., Seung-Keun Hong, Jin-Hwan Kim, Ming-Fong Lin, Jong-In Park Nov 2011

The Raf/Mek/Extracellular Signal-Regulated Kinase 1/2 Pathway Can Mediate Growth Inhibitory And Differentiation Signaling Via Androgen Receptor Downregulation In Prostate Cancer Cells., Seung-Keun Hong, Jin-Hwan Kim, Ming-Fong Lin, Jong-In Park

Journal Articles: Biochemistry & Molecular Biology

Upregulated ERK1/2 activity is correlated with androgen receptor (AR) downregulation in certain prostate cancer (PCa) that exhibits androgen deprivation-induced neuroendocrine differentiation, but its functional relevance requires elucidation. We found that sustained ERK1/2 activation using active Raf or MEK1/2 mutants is sufficient to induce AR downregulation at mRNA and protein levels in LNCaP. Downregulation of AR protein, but not mRNA, was blocked by proteasome inhibitors, MG132 and bortezomib, indicating that the pathway regulation is mediated at multiple points. Ectopic expression of a constitutively active AR inhibited Raf/MEK/ERK-mediated regulation of the differentiation markers, neuron-specific enolase and neutral endopeptidase, and the cyclin-dependent kinase …


Pathobiological Implications Of Muc16 Expression In Pancreatic Cancer., Dhanya Haridas, Subhankar Chakraborty, Moorthy P. Ponnusamy, Imayavaramban Lakshmanan, Satyanarayana Rachagani, Eric Cruz, Sushil Kumar, Srustidhar Das, Subodh M. Lele, Judy M. Anderson, Uwe A. Wittel, Michael A. Hollingsworth, Surinder K. Batra Oct 2011

Pathobiological Implications Of Muc16 Expression In Pancreatic Cancer., Dhanya Haridas, Subhankar Chakraborty, Moorthy P. Ponnusamy, Imayavaramban Lakshmanan, Satyanarayana Rachagani, Eric Cruz, Sushil Kumar, Srustidhar Das, Subodh M. Lele, Judy M. Anderson, Uwe A. Wittel, Michael A. Hollingsworth, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

MUC16 (CA125) belongs to a family of high-molecular weight O-glycosylated proteins known as mucins. While MUC16 is well known as a biomarker in ovarian cancer, its expression pattern in pancreatic cancer (PC), the fourth leading cause of cancer related deaths in the United States, remains unknown. The aim of our study was to analyze the expression of MUC16 during the initiation, progression and metastasis of PC for possible implication in PC diagnosis, prognosis and therapy. In this study, a microarray containing tissues from healthy and PC patients was used to investigate the differential protein expression of MUC16 in PC. MUC16 …


Human Rna Polymerase Ii-Association Factor 1 (Hpaf1/Pd2) Regulates Histone Methylation And Chromatin Remodeling In Pancreatic Cancer., Parama Dey, Moorthy P. Ponnusamy, Shonali Deb, Surinder K. Batra Oct 2011

Human Rna Polymerase Ii-Association Factor 1 (Hpaf1/Pd2) Regulates Histone Methylation And Chromatin Remodeling In Pancreatic Cancer., Parama Dey, Moorthy P. Ponnusamy, Shonali Deb, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Change in gene expression associated with pancreatic cancer could be attributed to the variation in histone posttranslational modifications leading to subsequent remodeling of the chromatin template during transcription. However, the interconnected network of molecules involved in regulating such processes remains elusive. hPaf1/PD2, a subunit of the human PAF-complex, involved in the regulation of transcriptional elongation has oncogenic potential. Our study explores the possibility that regulation of histone methylation by hPaf1 can contribute towards alteration in gene expression by nucleosomal rearrangement. Here, we show that knockdown of hPaf1/PD2 leads to decreased di- and tri-methylation at histone H3 lysine 4 residues in …


Potential Applications Of Curcumin And Its Novel Synthetic Analogs And Nanotechnology-Based Formulations In Cancer Prevention And Therapy., Murielle Mimeault, Surinder K. Batra Aug 2011

Potential Applications Of Curcumin And Its Novel Synthetic Analogs And Nanotechnology-Based Formulations In Cancer Prevention And Therapy., Murielle Mimeault, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Curcumin has attracted great attention in the therapeutic arsenal in clinical oncology due to its chemopreventive, antitumoral, radiosensibilizing and chemosensibilizing activities against various types of aggressive and recurrent cancers. These malignancies include leukemias, lymphomas, multiple myeloma, brain cancer, melanoma and skin, lung, prostate, breast, ovarian, liver, gastrointestinal, pancreatic and colorectal epithelial cancers. Curcumin mediates its anti-proliferative, anti-invasive and apoptotic effects on cancer cells, including cancer stem/progenitor cells and their progenies, through multiple molecular mechanisms. The oncogenic pathways inhibited by curcumin encompass the members of epidermal growth factor receptors (EGFR and erbB2), sonic hedgehog (SHH)/GLIs and Wnt/β-catenin and downstream signaling elements …


Monoclonal Antibodies Recognizing The Non-Tandem Repeat Regions Of The Human Mucin Muc4 In Pancreatic Cancer., Maneesh Jain, Ganesh Venkatraman, Nicolas Moniaux, Sukhwinder Kaur, Sushil Kumar, Subhankar Chakraborty, Grish C. Varshney, Surinder K. Batra Aug 2011

Monoclonal Antibodies Recognizing The Non-Tandem Repeat Regions Of The Human Mucin Muc4 In Pancreatic Cancer., Maneesh Jain, Ganesh Venkatraman, Nicolas Moniaux, Sukhwinder Kaur, Sushil Kumar, Subhankar Chakraborty, Grish C. Varshney, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

The MUC4 mucin is a high molecular weight, membrane-bound, and highly glycosylated protein. It is a multi-domain protein that is putatively cleaved into a large mucin-like subunit (MUC4α) and a C-terminal growth-factor like subunit (MUC4β). MUC4 plays critical roles in physiological and pathological conditions and is aberrantly overexpressed in several cancers, including those of the pancreas, cervix, breast and lung. It is also a potential biomarker for the diagnosis, prognosis and progression of several malignancies. Further, MUC4 plays diverse functional roles in cancer initiation and progression as evident from its involvement in oncogenic transformation, proliferation, inhibition of apoptosis, motility and …


A Role For Mir-296 In The Regulation Of Lipoapoptosis By Targeting Puma., Sophie C. Cazanave, Justin L. Mott, Nafisa A. Elmi, Steven F. Bronk, Howard C. Masuoka, Michael R. Charlton, Gregory J. Gores Aug 2011

A Role For Mir-296 In The Regulation Of Lipoapoptosis By Targeting Puma., Sophie C. Cazanave, Justin L. Mott, Nafisa A. Elmi, Steven F. Bronk, Howard C. Masuoka, Michael R. Charlton, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

Saturated free fatty acids (FFA) induce hepatocyte lipoapoptosis, a key mediator of liver injury in nonalcoholic fatty liver disease (NAFLD). Lipoapoptosis involves the upregulation of the BH3-only protein PUMA, a potent pro-apoptotic protein. Given that dysregulation of hepatic microRNA expression has been observed in NAFLD, we examined the role of miRNA in regulating PUMA expression during lipotoxicity. By in silico analysis, we identified two putative binding sites for miR-296-5p within the 3' untranslated region (UTR) of PUMA mRNA. Enforced miR-296-5p levels efficiently reduced PUMA protein expression in Huh-7 cells, while antagonism of miR-296-5p function increased PUMA cellular levels. Reporter gene …


Marital Status And Survival In Pancreatic Cancer Patients: A Seer Based Analysis., Michael J. Baine, Freshta Sahak, Chi Lin, Subhankar Chakraborty, Surinder K. Batra, Elizabeth R. Lyden Jun 2011

Marital Status And Survival In Pancreatic Cancer Patients: A Seer Based Analysis., Michael J. Baine, Freshta Sahak, Chi Lin, Subhankar Chakraborty, Surinder K. Batra, Elizabeth R. Lyden

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Recent findings suggest that marital status affects survival in patients with different types of cancer. However, its role in the survival of patients with pancreatic ductal adenocarcinoma is unknown. In this study, we investigated whether there was an association between marital status and overall survival (OS) in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS: Adult patients diagnosed with PDAC between 1998 and 2003 with known marital statuses were identified from the Surveillance, Epidemiology, and End Results registry of the National Cancer Institute. OS for these patients was plotted using the Kaplan-Meier method. Comparative risks of mortality were evaluated by …


Tnfα Enhances The Motility And Invasiveness Of Prostatic Cancer Cells By Stimulating The Expression Of Selective Glycosyl- And Sulfotransferase Genes Involved In The Synthesis Of Selectin Ligands., Prakash Radhakrishnan, Vishwanath Chachadi, Ming-Fong Lin, Rakesh Singh, Reiji Kannagi, Pi-Wan Cheng Jun 2011

Tnfα Enhances The Motility And Invasiveness Of Prostatic Cancer Cells By Stimulating The Expression Of Selective Glycosyl- And Sulfotransferase Genes Involved In The Synthesis Of Selectin Ligands., Prakash Radhakrishnan, Vishwanath Chachadi, Ming-Fong Lin, Rakesh Singh, Reiji Kannagi, Pi-Wan Cheng

Journal Articles: Biochemistry & Molecular Biology

Sialyl Lewis x (sLe(x)) plays an important role in cancer metastasis. But, the mechanism for its production in metastatic cancers remains unclear. The objective of current study was to examine the effects of a proinflammatory cytokine on the expression of glycosyltransferase and sulfotransferase genes involved in the synthesis of selectin ligands in a prostate cancer cell line. Androgen-independent human lymph node-derived metastatic prostate cancer cells (C-81 LNCaP), which express functional androgen receptor and mimic the castration-resistant advanced prostate cancer, were used. TNFα treatment of these cells increased their binding to P-, E- and L-selectins, anti-sLe(x) antibody, and anti-6-sulfo-sialyl Lewis x …


Mediator Influences Telomeric Silencing And Cellular Life Span, Xuefeng Zhu, Beidong Liu, Jonas O. P. Carlsten, Jenny Beve, Thomas Nyström, Lawrence C. Myers, Claes M. Gustafsson Jun 2011

Mediator Influences Telomeric Silencing And Cellular Life Span, Xuefeng Zhu, Beidong Liu, Jonas O. P. Carlsten, Jenny Beve, Thomas Nyström, Lawrence C. Myers, Claes M. Gustafsson

Dartmouth Scholarship

The Mediator complex is required for the regulated transcription of nearly all RNA polymerase II-dependent genes. Here we demonstrate a new role for Mediator which appears to be separate from its function as a transcriptional coactivator. Mediator associates directly with heterochromatin at telomeres and influences the exact boundary between active and inactive chromatin. Loss of the Mediator Med5 subunit or mutations in Med7 cause a depletion of the complex from regions located near subtelomeric X elements, which leads to a change in the balance between the Sir2 and Sas2 proteins. These changes in turn result in increased levels of H4K16 …


Structure Of The Atp Synthase Catalytic Complex (F(1)) From Escherichia Coli In An Autoinhibited Conformation., Gino Cingolani, Thomas M Duncan Jun 2011

Structure Of The Atp Synthase Catalytic Complex (F(1)) From Escherichia Coli In An Autoinhibited Conformation., Gino Cingolani, Thomas M Duncan

Department of Biochemistry and Molecular Biology Faculty Papers

ATP synthase is a membrane-bound rotary motor enzyme that is critical for cellular energy metabolism in all kingdoms of life. Despite conservation of its basic structure and function, autoinhibition by one of its rotary stalk subunits occurs in bacteria and chloroplasts but not in mitochondria. The crystal structure of the ATP synthase catalytic complex (F(1)) from Escherichia coli described here reveals the structural basis for this inhibition. The C-terminal domain of subunit ɛ adopts a heretofore unknown, highly extended conformation that inserts deeply into the central cavity of the enzyme and engages both rotor and stator subunits in extensive contacts …


Muc4 Stabilizes Her2 Expression And Maintains The Cancer Stem Cell Population In Ovarian Cancer Cells., Moorthy P. Ponnusamy, Parthasarathy Seshacharyulu, Arokia P. Vaz, Parama Dey, Surinder K. Batra Apr 2011

Muc4 Stabilizes Her2 Expression And Maintains The Cancer Stem Cell Population In Ovarian Cancer Cells., Moorthy P. Ponnusamy, Parthasarathy Seshacharyulu, Arokia P. Vaz, Parama Dey, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Recent evidence has suggested that the capability of cancer to grow, propagate and relapse after therapy is dependent on a small subset of the cell population within the tumor, called cancer stem cells. Therefore, this subpopulation of cells needs to be targeted with different approaches by identification of unique stem-cell specific target antigens. One of the well known tumor antigens is the epithelial cell mucin MUC4, which is aberrantly expressed in ovarian cancer as compared to the normal ovary and plays a pivotal role in the aggressiveness and metastasis of ovarian cancer cells. In the present study, we aimed …


Activated Krasg¹²D Is Associated With Invasion And Metastasis Of Pancreatic Cancer Cells Through Inhibition Of E-Cadherin., Satyanarayana Rachagani, S Senapati, S Chakraborty, Moorthy P. Ponnusamy, Sushil Kumar, Lynette Smith, Maneesh Jain, Surinder K. Batra Mar 2011

Activated Krasg¹²D Is Associated With Invasion And Metastasis Of Pancreatic Cancer Cells Through Inhibition Of E-Cadherin., Satyanarayana Rachagani, S Senapati, S Chakraborty, Moorthy P. Ponnusamy, Sushil Kumar, Lynette Smith, Maneesh Jain, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Pancreatic cancer (PC) harbours an activated point mutation (Kras(G12D)) in the Kras proto-oncogene that has been demonstrated to promote the development of PC.

METHODS: This study was designed to investigate the effect of the oncogenic Kras(G12D) allele on aggressiveness and metastatic potential of PC cells. We silenced the oncogenic Kras(G12D) allele expression in CD18/HPAF and ASPC1 cell lines by stable expression of shRNA specific to the Kras(G12D)allele.

RESULTS: The Kras(G12D) knockdown cells exhibited a significant decrease in motility (P

CONCLUSIONS: The results of this study suggest that the Kras(G12D) allele promotes metastasis in PC cells partly through the downregulation …


Progressive Multifocal Leukoencephalopathy In A Hiv-Negative Patient With Small Lymphocytic Leukemia Following Treatment With Rituximab., Subhankar Chakraborty, Stefano R. Tarantolo, John Treves, David Sambol, Ralph J. Hauke, Surinder K. Batra Mar 2011

Progressive Multifocal Leukoencephalopathy In A Hiv-Negative Patient With Small Lymphocytic Leukemia Following Treatment With Rituximab., Subhankar Chakraborty, Stefano R. Tarantolo, John Treves, David Sambol, Ralph J. Hauke, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

We describe a case of progressive multifocal leukoencephalopathy (PML) caused by infection with the human polyomavirus JC virus in a patient with B-cell small lymphocytic leukemia who was treated with rituximab. The first symptoms of PML appeared immediately following the last of five cycles of rituximab, cyclophosphamide and pentostatin. Magnetic resonance imaging revealed changes consistent with PML, although JC virus DNA was not detected by polymerase chain reaction assay of the cerebrospinal fluid. A stereotactic biopsy of the brain showed histological changes consistent with PML, while electron microscopy revealed JC virus particles attached to the nuclei of astrocytes. The patient …


Hedgehog Inhibition Promotes A Switch From Type Ii To Type I Cell Death Receptor Signaling In Cancer Cells., Satoshi Kurita, Justin L. Mott, Sophie C. Cazanave, Christian D. Fingas, Maria E. Guicciardi, Steve F. Bronk, Lewis R. Roberts, Martin E. Fernandez-Zapico, Gregory J. Gores Mar 2011

Hedgehog Inhibition Promotes A Switch From Type Ii To Type I Cell Death Receptor Signaling In Cancer Cells., Satoshi Kurita, Justin L. Mott, Sophie C. Cazanave, Christian D. Fingas, Maria E. Guicciardi, Steve F. Bronk, Lewis R. Roberts, Martin E. Fernandez-Zapico, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

TRAIL is a promising therapeutic agent for human malignancies. TRAIL often requires mitochondrial dysfunction, referred to as the Type II death receptor pathway, to promote cytotoxicity. However, numerous malignant cells are TRAIL resistant due to inhibition of this mitochondrial pathway. Using cholangiocarcinoma cells as a model of TRAIL resistance, we found that Hedgehog signaling blockade sensitized these cancer cells to TRAIL cytotoxicity independent of mitochondrial dysfunction, referred to as Type I death receptor signaling. This switch in TRAIL requirement from Type II to Type I death receptor signaling was demonstrated by the lack of functional dependence on Bid/Bim and Bax/Bak, …


Transcriptional Profiling Of Peripheral Blood Mononuclear Cells In Pancreatic Cancer Patients Identifies Novel Genes With Potential Diagnostic Utility., Michael J. Baine, Subhankar Chakraborty, Lynette M. Smith, Kavita Mallya, Aaron R. Sasson, Randall E. Brand, Surinder K. Batra Feb 2011

Transcriptional Profiling Of Peripheral Blood Mononuclear Cells In Pancreatic Cancer Patients Identifies Novel Genes With Potential Diagnostic Utility., Michael J. Baine, Subhankar Chakraborty, Lynette M. Smith, Kavita Mallya, Aaron R. Sasson, Randall E. Brand, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: It is well known that many malignancies, including pancreatic cancer (PC), possess the ability to evade the immune system by indirectly downregulating the mononuclear cell machinery necessary to launch an effective immune response. This knowledge, in conjunction with the fact that the trancriptome of peripheral blood mononuclear cells has been shown to be altered in the context of many diseases, including renal cell carcinoma, lead us to study if any such alteration in gene expression exists in PC as it may have diagnostic utility.

METHODS AND FINDINGS: PBMC samples from 26 PC patients and 33 matched healthy controls were …


Three Dimensional Projection Environment For Molecular Design And Surgical Simulation, Matthew Wampole, Eric Wickstrom, Chang-Po Chen, Devakumar Devadhas, Yuan-Yuan Jin, Jeffrey M. Sanders, John C. Kairys, Martha L. Ankeny, Rui Hu, Kenneth E. Barner, Karl V. Steiner, Mathew L. Thakur Feb 2011

Three Dimensional Projection Environment For Molecular Design And Surgical Simulation, Matthew Wampole, Eric Wickstrom, Chang-Po Chen, Devakumar Devadhas, Yuan-Yuan Jin, Jeffrey M. Sanders, John C. Kairys, Martha L. Ankeny, Rui Hu, Kenneth E. Barner, Karl V. Steiner, Mathew L. Thakur

Department of Biochemistry and Molecular Biology Faculty Papers

Poster presented at "Medicine Meets Virtual Reality" conference February 8-12, 2011 in Newport Beach, California.

Conclusions:

Turning 2D CT/PET slices into 3D objects assists in understanding the topology surrounding tumor masses. Incorporating the visual and physical characteristics of a patient’s anatomy will provide surgeons with an informative pre-operative tool to plan and practice the operation before the first incision. Including haptic feedback provides a familiar 'feel' to surgeons as they palpate the target organ, trying to locate the tumor and determine how large a margin of resection will be needed. The development of genetic PET imaging and contrast CT into …


Steroids Up-Regulate P66shc Longevity Protein In Growth Regulation By Inhibiting Its Ubiquitination., Santosh Kumar, Satyendra Kumar, Mythilypriya Rajendran, Syed Mahfuzul Alam, Fen-Fen Lin, Pi-Wan Cheng, Ming-Fong Lin Jan 2011

Steroids Up-Regulate P66shc Longevity Protein In Growth Regulation By Inhibiting Its Ubiquitination., Santosh Kumar, Satyendra Kumar, Mythilypriya Rajendran, Syed Mahfuzul Alam, Fen-Fen Lin, Pi-Wan Cheng, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: p66Shc, an isoform of Shc adaptor proteins, mediates diverse signals, including cellular stress and mouse longevity. p66Shc protein level is elevated in several carcinomas and steroid-treated human cancer cells. Several lines of evidence indicate that p66Shc plays a critical role in steroid-related carcinogenesis, and steroids play a role in its elevated levels in those cells without known mechanism.

METHODS AND FINDINGS: In this study, we investigated the molecular mechanism by which steroid hormones up-regulate p66Shc protein level. In steroid-treated human prostate and ovarian cancer cells, p66Shc protein levels were elevated, correlating with increased cell proliferation. These steroid effects on …


Mir-27b*, An Oxidative Stress-Responsive Microrna Modulates Nuclear Factor-Kb Pathway In Raw 264.7 Cells, Sivasubramani Thulasingam, Chandirasegaran Massilamany, Arunakumar Gangaplara, Hongjiu Dai, Shahlo Yarbaeva, Sakthivel Subramaniam, Jean-Jack Riethoven, James Eudy, Marjorie F. Lou, Jay Reddy Jan 2011

Mir-27b*, An Oxidative Stress-Responsive Microrna Modulates Nuclear Factor-Kb Pathway In Raw 264.7 Cells, Sivasubramani Thulasingam, Chandirasegaran Massilamany, Arunakumar Gangaplara, Hongjiu Dai, Shahlo Yarbaeva, Sakthivel Subramaniam, Jean-Jack Riethoven, James Eudy, Marjorie F. Lou, Jay Reddy

Jay Reddy Publications

Reactive oxygen species (ROS) produced in macrophages is critical for microbial killing, but they also take part in inflammation and antigen presentation functions. MicroRNAs (miRNAs) are endogenous regulators of gene expression, and they can control immune responses. To dissect the complex nature of ROS-mediated effects in macrophages, we sought to characterize miRNAs that are responsive to oxidative stress-induced with hydrogen peroxide (H2O2) in the mouse macrophage cell line, RAW 264.7. We have identified a set of unique miRNAs that are differentially expressed in response to H2O2. These include miR-27a*, miR-27b*, miR-29b*, miR-24-2*, …


Protein Modification By Arginylation, Hideko Kaji, Akira Kaji Jan 2011

Protein Modification By Arginylation, Hideko Kaji, Akira Kaji

Department of Biochemistry and Molecular Biology Faculty Papers

The modification of protein by arginine catalyzed by arginyltransferases (ATE1) described by the Kashina group in this issue shows that arginylation of protein occurs widely in biology and is being recognized as a key regulatory reaction such as phosphorylation of proteins (Wang et al., 2011).