Life Sciences Commons^™

Predictive And Prognostic Biomarkers And Tumor Antigens For Targeted Therapy In Urothelial Carcinoma, Aditya Eturi, Amman Bhasin, Kevin Zarrabi, William Tester

Department of Medical Oncology Faculty Papers

Urothelial carcinoma (UC) is the fourth most prevalent cancer amongst males worldwide. While patients with non-muscle-invasive disease have a favorable prognosis, 25% of UC patients present with locally advanced disease which is associated with a 10-15% 5-year survival rate and poor overall prognosis. Muscle-invasive bladder cancer (MIBC) is associated with about 50% 5 year survival when treated by radical cystectomy or trimodality therapy; stage IV disease is associated with 10-15% 5 year survival. Current therapeutic modalities for MIBC include neoadjuvant chemotherapy, surgery and/or chemoradiation, although patients with relapsed or refractory disease have a poor prognosis. However, the rapid success of …

Discovery Of A Small-Molecule Inhibitor That Traps Polθ On Dna And Synergizes With Parp Inhibitors, William Fried, Mrityunjay Tyagi, Leonid Minakhin, Gurushankar Chandramouly, Taylor Tredinnick, Mercy Ramanjulu, William Auerbacher, Marissa L Calbert, Timur Rusanov, Trung Hoang, Nikita Borisonnik, Robert Betsch, John Krais, Yifan Wang, Umeshkumar Vekariya, John Gordon, George Morton, Tatiana Kent, Tomasz Skorski, Neil Johnson, Wayne Childers, Xiaojiang Chen, Richard Pomerantz

Department of Biochemistry and Molecular Biology Faculty Papers

The DNA damage response (DDR) protein DNA Polymerase θ (Polθ) is synthetic lethal with homologous recombination (HR) factors and is therefore a promising drug target in BRCA1/2 mutant cancers. We discover an allosteric Polθ inhibitor (Polθi) class with 4-6 nM IC₅₀ that selectively kills HR-deficient cells and acts synergistically with PARP inhibitors (PARPi) in multiple genetic backgrounds. X-ray crystallography and biochemistry reveal that Polθi selectively inhibits Polθ polymerase (Polθ-pol) in the closed conformation on B-form DNA/DNA via an induced fit mechanism. In contrast, Polθi fails to inhibit Polθ-pol catalytic activity on A-form DNA/RNA in which the enzyme binds in …

Parp2 Promotes Break Induced Replication-Mediated Telomere Fragility In Response To Replication Stress, Daniela Muoio, Natalie Laspata, Rachel L Dannenberg, Caroline Curry, Simone Darkoa-Larbi, Mark Hedglin, Shikhar Uttam, Elise Fouquerel

Department of Biochemistry and Molecular Biology Faculty Papers

PARP2 is a DNA-dependent ADP-ribosyl transferase (ARTs) enzyme with Poly(ADP-ribosyl)ation activity that is triggered by DNA breaks. It plays a role in the Base Excision Repair pathway, where it has overlapping functions with PARP1. However, additional roles for PARP2 have emerged in the response of cells to replication stress. In this study, we demonstrate that PARP2 promotes replication stress-induced telomere fragility and prevents telomere loss following chronic induction of oxidative DNA lesions and BLM helicase depletion. Telomere fragility results from the activity of the break-induced replication pathway (BIR). During this process, PARP2 promotes DNA end resection, strand invasion and BIR-dependent …

Blocking The Dimerization Of Polyglutamine-Expanded Androgen Receptor Protects Cells From Dht-Induced Toxicity By Increasing Ar Turnover, Allison Lisberg, Yuhong Liu, Diane E. Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular degenerative disease caused by a polyglutamine expansion in the androgen receptor (AR). This mutation causes AR to misfold and aggregate, contributing to toxicity in and degeneration of motor neurons and skeletal muscle. There is currently no effective treatment or cure for this disease. The role of an interdomain interaction between the amino- and carboxyl-termini of AR, termed the N/C interaction, has been previously identified as a component of androgen receptor-induced toxicity in cell and mouse models of SBMA. However, the mechanism by which this interaction contributes to disease pathology is unclear. …

Biomarkers For Managing Neurodegenerative Diseases, Lara Cheslow, Adam E. Snook, Scott A. Waldman

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Neurological disorders are the leading cause of cognitive and physical disability worldwide, affecting 15% of the global population. Due to the demographics of aging, the prevalence of neurological disorders, including neurodegenerative diseases, will double over the next two decades. Unfortunately, while available therapies provide symptomatic relief for cognitive and motor impairment, there is an urgent unmet need to develop disease-modifying therapies that slow the rate of pathological progression. In that context, biomarkers could identify at-risk and prodromal patients, monitor disease progression, track responses to therapy, and parse the causality of molecular events to identify novel targets for further clinical investigation. …

Two Dot1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation In Kinetoplastids, Victoria Frisbie, Hideharu Hashimoto, Yixuan Xie, Francisca De Luna Vitorino, Josue Baeza, Tam Nguyen, Zhangerjiao Yuan, Janna Kiselar, Benjamin Garcia, Erik Debler

Department of Biochemistry and Molecular Biology Faculty Papers

In higher eukaryotes, a single DOT1 histone H3 lysine 79 (H3K79) methyltransferase processively produces H3K79me2/me3 through histone H2B mono-ubiquitin interaction, while the kinetoplastid Trypanosoma brucei di-methyltransferase DOT1A and tri-methyltransferase DOT1B efficiently methylate the homologous H3K76 without H2B mono-ubiquitination. Based on structural and biochemical analyses of DOT1A, we identify key residues in the methyltransferase motifs VI and X for efficient ubiquitin-independent H3K76 methylation in kinetoplastids. Substitution of a basic to an acidic residue within motif VI (Gx₆K) is essential to stabilize the DOT1A enzyme-substrate complex, while substitution of the motif X sequence VYGE by CAKS renders a rigid active-site …

Differentially Disrupted Spinal Cord And Muscle Energy Metabolism In Spinal And Bulbar Muscular Atrophy, Danielle Debartolo, Frederick Arnold, Y Liu, Elana Molotsky, Hsin-Yao Tang, Diane Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Prior studies showed that polyglutamine-expanded androgen receptor (AR) is aberrantly acetylated and that deacetylation of the mutant AR by overexpression of nicotinamide adenine dinucleotide-dependent (NAD+-dependent) sirtuin 1 is protective in cell models of spinal and bulbar muscular atrophy (SBMA). Based on these observations and reduced NAD+ in muscles of SBMA mouse models, we tested the therapeutic potential of NAD+ restoration in vivo by treating postsymptomatic transgenic SBMA mice with the NAD+ precursor nicotinamide riboside (NR). NR supplementation failed to alter disease progression and had no effect on increasing NAD+ or ATP content in muscle, despite producing a modest increase of …

Editorial: Pharmacology Of Endocrine Related Gpcrs, Francesco De Pascali, Aylin Hanyaloglu, Frederic Jean-Alphonse, Francesco Potì, Eric Reiter

Department of Biochemistry and Molecular Biology Faculty Papers

No abstract provided.

Tail-Tape-Fused Virion And Non-Virion Rna Polymerases Of A Thermophilic Virus With An Extremely Long Tail, Anastasiia Chaban, Leonid Minakhin, Ekaterina Goldobina, Brain Bae, Yue Hao, Sergei Borukhov, Leena Putzeys, Maarten Boon, Florian Kabinger, Rob Lavigne, Kira Makarova, Eugene V Koonin, Satish Nair, Shunsuke Tagami, Konstantin Severinov, Maria Sokolova

Department of Biochemistry and Molecular Biology Faculty Papers

Thermus thermophilus bacteriophage P23-45 encodes a giant 5,002-residue tail tape measure protein (TMP) that defines the length of its extraordinarily long tail. Here, we show that the N-terminal portion of P23-45 TMP is an unusual RNA polymerase (RNAP) homologous to cellular RNAPs. The TMP-fused virion RNAP transcribes pre-early phage genes, including a gene that encodes another, non-virion RNAP, that transcribes early and some middle phage genes. We report the crystal structures of both P23-45 RNAPs. The non-virion RNAP has a crab-claw-like architecture. By contrast, the virion RNAP adopts a unique flat structure without a clamp. Structure and sequence comparisons of …

Structural Basis For Dna Proofreading, Gina Buchel, Ashok Nayak, Karl Herbine, Azadeh Sarfallah, Viktoriia Sokolova, Angelica Zamudio-Ochoa, Dmitry Temiakov

Department of Biochemistry and Molecular Biology Faculty Papers

DNA polymerase (DNAP) can correct errors in DNA during replication by proofreading, a process critical for cell viability. However, the mechanism by which an erroneously incorporated base translocates from the polymerase to the exonuclease site and the corrected DNA terminus returns has remained elusive. Here, we present an ensemble of nine high-resolution structures representing human mitochondrial DNA polymerase Gamma, Polγ, captured during consecutive proofreading steps. The structures reveal key events, including mismatched base recognition, its dissociation from the polymerase site, forward translocation of DNAP, alterations in DNA trajectory, repositioning and refolding of elements for primer separation, DNAP backtracking, and displacement …

Novel Treatments For Pxe: Targeting The Systemic And Local Drivers Of Ectopic Calcification, Ida Joely Jacobs, Qiaoli Li

Department of Biochemistry and Molecular Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable multisystem ectopic calcification disorder. The gene responsible for PXE, ABCC6, encodes ABCC6, a hepatic efflux transporter regulating extracellular inorganic pyrophosphate (PPi), a potent endogenous calcification inhibitor. Recent studies demonstrated that in addition to the deficiency of plasma PPi, the activated DDR/PARP signaling in calcified tissues provides an additional possible mechanism of ectopic calcification in PXE. This study examined the effects of etidronate (ETD), a stable PPi analog, and its combination with minocycline (Mino), a potent inhibitor of DDR/PARP, on ectopic calcification in an Abcc6-/- mouse model of PXE. Abcc6-/- mice, at 4 weeks of …

Loss Of Pml Nuclear Bodies In Familial Amyotrophic Lateral Sclerosis-Frontotemporal Dementia, Francesco Antoniani, Marco Cimino, Laura Mediani, Jonathan Vinet, Enza M. Verde, Valentina Secco, Alfred Yamoah, Priyanka Tripathi, Eleonora Aronica, Maria Elena Cicardi, Davide Trotti, Jared Sterneckert, Anand Goswami, Serena Carra

Farber Institute for Neuroscience Faculty Papers

Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) are two neurodegenerative disorders that share genetic causes and pathogenic mechanisms. The critical genetic players of ALS and FTD are the TARDBP, FUS and C9orf72 genes, whose protein products, TDP-43, FUS and the C9orf72-dipeptide repeat proteins, accumulate in form of cytoplasmic inclusions. The majority of the studies focus on the understanding of how cells control TDP-43 and FUS aggregation in the cytoplasm, overlooking how dysfunctions occurring at the nuclear level may influence the maintenance of protein solubility outside of the nucleus. However, protein quality control (PQC) systems that maintain protein homeostasis comprise …

High-Resolution Cryo-Em Structure Of The Pseudomonas Bacteriophage E217, Fenglin Li, Chun-Feng Hou, Ravi K. Lokareddy, Ruoyu Yang, Francesca Forti, Federica Briani, Gino Cingolani

Department of Biochemistry and Molecular Biology Faculty Papers

E217 is a Pseudomonas phage used in an experimental cocktail to eradicate cystic fibrosis-associated Pseudomonas aeruginosa. Here, we describe the structure of the whole E217 virion before and after DNA ejection at 3.1 Å and 4.5 Å resolution, respectively, determined using cryogenic electron microscopy (cryo-EM). We identify and build de novo structures for 19 unique E217 gene products, resolve the tail genome-ejection machine in both extended and contracted states, and decipher the complete architecture of the baseplate formed by 66 polypeptide chains. We also determine that E217 recognizes the host O-antigen as a receptor, and we resolve the N-terminal portion …

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …

Molecular Mechanisms Protecting Centromeres From Self-Sabotage And Implications For Cancer Therapy, Rim Nassar, Lily Thompson, Elise Fouquerel

Student Papers, Posters & Projects

Centromeres play a crucial role in DNA segregation by mediating the cohesion and separation of sister chromatids during cell division. Centromere dysfunction, breakage or compromised centromeric integrity can generate aneuploidies and chromosomal instability, which are cellular features associated with cancer initiation and progression. Maintaining centromere integrity is thus essential for genome stability. However, the centromere itself is prone to DNA breaks, likely due to its intrinsically fragile nature. Centromeres are complex genomic loci that are composed of highly repetitive DNA sequences and secondary structures and require the recruitment and homeostasis of a centromere-associated protein network. The molecular mechanisms engaged to …

Physicochemical Analysis Of Cold Brew And Hot Brew Peaberry Coffee, Evan T. Schwarzmann, Marlena P. Washington, Niny Z. Rao

College of Life Sciences Faculty Papers

Peaberry coffee is the result of a natural mutation of coffee beans, and they make up only about 5–7% of coffee crops. A typical coffee cherry contains two seeds that are developed against each other, resulting in the distinctive half-rounded shape of coffee beans. However, failing to fertilize both ovules of one of the seeds or failure in endosperm development can cause only one of the seeds to develop, resulting in smaller, denser beans with a more domed shape. Peaberry coffees are said to be sweeter, lighter, and more flavorful since the peaberry beans receive all nutrients from the coffee …

Quantification Of Spent Coffee Ground Extracts By Roast And Brew Method, And Their Utility In A Green Synthesis Of Gold And Silver Nanoparticles, Brian G Yust, Niny Z Rao, Evan T Schwarzmann, Madisyn H Peoples

College of Life Sciences Faculty Papers

Nanotechnology has become increasingly important in modern society, and nanoparticles are routinely used in many areas of technology, industry, and commercial products. Many species of nanoparticle (NP) are typically synthesized using toxic or hazardous chemicals, making these methods less environmentally friendly. Consequently, there has been growing interest in green synthesis methods, which avoid unnecessary exposure to toxic chemicals and reduce harmful waste. Synthesis methods which utilize food waste products are particularly attractive because they add value and a secondary use for material which would otherwise be disposed of. Here, we show that spent coffee grounds (SCGs) that have already been …

Targeting The Cdk6 Dependence Of Ph+ Acute Lymphoblastic Leukemia, Patrizia Porazzi, Marco De Dominici, Joseph Salvino, Bruno Calabretta

Department of Cancer Biology Faculty Papers

Ph+ ALL is a poor-prognosis leukemia subtype driven by the BCR-ABL1 oncogene, either the p190-or the p210-BCR/ABL isoform in a 70:30 ratio. Tyrosine Kinase inhibitors (TKIs) are the drugs of choice in the therapy of Ph+ ALL. In combination with standard chemotherapy, TKIs have markedly improved the outcome of Ph+ ALL, in particular if this treatment is followed by bone marrow transplantation. However, resistance to TKIs develops with high frequency, causing leukemia relapse that results in

Biophysical Analysis Of Pseudomonas-Phage Pap3 Small Terminase Suggests A Mechanism For Sequence-Specific Dna-Binding By Lateral Interdigitation., Marzia Niazi, Tyler J. Florio, Ruoyu Yang, Ravi K. Lokareddy, Nicholas A. Swanson, Richard E. Gillilan, Gino Cingolani

Department of Biochemistry and Molecular Biology Faculty Papers

The genome packaging motor of tailed bacteriophages and herpesviruses is a powerful nanomachine built by several copies of a large (TerL) and a small (TerS) terminase subunit. The motor assembles transiently at the portal vertex of an empty precursor capsid (or procapsid) to power genome encapsidation. Terminase subunits have been studied in-depth, especially in classical bacteriophages that infect Escherichia coli or Salmonella, yet, less is known about the packaging motor of Pseudomonas-phages that have increasing biomedical relevance. Here, we investigated the small terminase subunit from three Podoviridae phages that infect Pseudomonas aeruginosa. We found TerS is polymorphic in solution but …

A Label-Free Assay For Aminoacylation Of Trna, Howard Gamper, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

Aminoacylation of tRNA generates an aminoacyl-tRNA (aa-tRNA) that is active for protein synthesis on the ribosome. Quantification of aminoacylation of tRNA is critical to understand the mechanism of specificity and the flux of the aa-tRNA into the protein synthesis machinery, which determines the rate of cell growth. Traditional assays for the quantification of tRNA aminoacylation involve radioactivity, either with a radioactive amino acid or with a [3'-32P]-labeled tRNA. We describe here a label-free assay that monitors aminoacylation by biotinylation-streptavidin (SA) conjugation to the α-amine or the α-imine of the aminoacyl group on the aa-tRNA. The conjugated aa-tRNA product is readily …

Profiling The Circulating Mrna Transcriptome In Human Liver Disease, Aejaz Sayeed, Brielle E Dalvano, David E Kaplan, Usha Viswanathan, John Kulp, Alhaji H Janneh, Lu-Yu Hwang, Adam Ertel, Cataldo Doria, Timothy Block

Department of Cancer Biology Faculty Papers

The human circulation contains cell-free DNA and non-coding microRNA (miRNA). Less is known about the presence of messenger RNA (mRNA). This report profiles the human circulating mRNA transcriptome in people with liver cirrhosis (LC) and hepatocellular carcinoma (HCC) to determine whether mRNA analytes can be used as biomarkers of liver disease. Using RNAseq and RT-qPCR, we investigate circulating mRNA in plasma from HCC and LC patients and demonstrate detection of transcripts representing more than 19,000 different protein coding genes. Remarkably, the circulating mRNA expression levels were similar from person to person over the 21 individuals whose samples were analyzed by …

Methylation Of Salmonella Typhimurium Flagella Promotes Bacterial Adhesion And Host Cell Invasion, Julia A Horstmann, Michele Lunelli, Hélène Cazzola, Johannes Heidemann, Caroline Kühne, Pascal Steffen, Sandra Szefs, Claire Rossi, Ravi K Lokareddy, Chu Wang, Laurine Lemaire, Kelly T Hughes, Charlotte Uetrecht, Hartmut Schlüter, Guntram A Grassl, Theresia E B Stradal, Yannick Rossez, Michael Kolbe, Marc Erhardt

Department of Biochemistry and Molecular Biology Faculty Papers

The long external filament of bacterial flagella is composed of several thousand copies of a single protein, flagellin. Here, we explore the role played by lysine methylation of flagellin in Salmonella, which requires the methylase FliB. We show that both flagellins of Salmonella enterica serovar Typhimurium, FliC and FljB, are methylated at surface-exposed lysine residues by FliB. A Salmonella Typhimurium mutant deficient in flagellin methylation is outcompeted for gut colonization in a gastroenteritis mouse model, and methylation of flagellin promotes bacterial invasion of epithelial cells in vitro. Lysine methylation increases the surface hydrophobicity of flagellin, and enhances flagella-dependent adhesion of …

Methylation Of Salmonella Typhimurium Flagella Promotes Bacterial Adhesion And Host Cell Invasion., Julia A Horstmann, Michele Lunelli, Hélène Cazzola, Johannes Heidemann, Caroline Kühne, Pascal Steffen, Sandra Szefs, Claire Rossi, Ravi K Lokareddy, Chu Wang, Laurine Lemaire, Kelly T Hughes, Charlotte Uetrecht, Hartmut Schlüter, Guntram A Grassl, Theresia E B Stradal, Yannick Rossez, Michael Kolbe, Marc Erhardt

Department of Biochemistry and Molecular Biology Faculty Papers

The long external filament of bacterial flagella is composed of several thousand copies of a single protein, flagellin. Here, we explore the role played by lysine methylation of flagellin in Salmonella, which requires the methylase FliB. We show that both flagellins of Salmonella enterica serovar Typhimurium, FliC and FljB, are methylated at surface-exposed lysine residues by FliB. A Salmonella Typhimurium mutant deficient in flagellin methylation is outcompeted for gut colonization in a gastroenteritis mouse model, and methylation of flagellin promotes bacterial invasion of epithelial cells in vitro. Lysine methylation increases the surface hydrophobicity of flagellin, and enhances flagella-dependent adhesion of …

How To Untie A Protein Knot., Sitao Yin, Brittiny Dhital, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

The origin of protein backbone threading through a topological knot remains elusive. To understand the evolutionary origin of protein knots, in this issue of StructureKo et al. (2019) used circular permutation to untie a knotted protein. They showed that a domain-swapped dimer releases the knot and the associated high-energy state for substrate binding.

Acidity And Antioxidant Activity Of Cold Brew Coffee., Niny Z. Rao, Megan Fuller

College of Life Sciences Faculty Papers

The acidity and antioxidant activity of cold brew coffee were investigated using light roast coffees from Brazil, two regions of Ethiopia, Columbia, Myanmar, and Mexico. The concentrations of three caffeoylquinic acid (CQA) isomers were also determined. Cold brew coffee chemistry was compared to that of hot brew coffee prepared with the same grind-to-coffee ratio. The pH values of the cold and hot brew samples were found to be comparable, ranging from 4.85 to 5.13. The hot brew coffees were found to have higher concentrations of total titratable acids, as well as higher antioxidant activity, than that of their cold brew …

The Structure And C=C Vibrational Frequencies Of The All- Trans Polyenes C2nh2n+2(N=2-15), C2nh2n(Me)2(N=2-13), And C2nh2n(Tert-Butyl)2(N=2-5): Computational Results, George R. De Maré, Niny Z. Rao, Charles W. Block

Department of Biochemistry and Molecular Biology Faculty Papers

Carbon-carbon bond lengths and C=C vibrational frequencies are reported for the linear, all-trans unsubstituted C2nH2n+2 (n=2-15), methyl capped C2nH2nMe2 (n=2-13), and tert-butyl capped C2nH2n(tert-butyl)2 (n=2-5) polyenes (C2h) calculated at the B3LYP/6-311++G(d,p) level. The C=C/C-C bond length alternation remains evident at this level for the unsubstituted and methyl capped polyenes as the chain length increases; the center-most difference in the length of the C-C/C=C bonds is ~0.06 Å for C30H32 and C26H26Me2. The Ag, in-phase, harmonic C=C Raman frequency for the unsubstituted polyenes decreases from 1699.2 cm-1 (n = 2) to 1528.9 cm-1 (n=15); the anharmonic frequency decreases from 1651.5 cm-1 …

Using Competition Assays To Quantitatively Model Cooperative Binding By Transcription Factors And Other Ligands., Jacob Peacock, James B Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

BACKGROUND: The affinities of DNA binding proteins for target sites can be used to model the regulation of gene expression. These proteins can bind to DNA cooperatively, strongly impacting their affinity and specificity. However, current methods for measuring cooperativity do not provide the means to accurately predict binding behavior over a wide range of concentrations.

METHODS: We use standard computational and mathematical methods, and develop novel methods as described in Results.

RESULTS: We explore some complexities of cooperative binding, and develop an improved method for relating in vitro measurements to in vivo function, based on ternary complex formation. We derive …

Decorin As A Multivalent Therapeutic Agent Against Cancer., Thomas Neill, Liliana Schaefer, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Decorin is a prototypical small leucine-rich proteoglycan that epitomizes the multifunctional nature of this critical gene family. Soluble decorin engages multiple receptor tyrosine kinases within the target-rich environment of the tumor stroma and tumor parenchyma. Upon receptor binding, decorin initiates signaling pathways within endothelial cells downstream of VEGFR2 that ultimately culminate in a Peg3/Beclin 1/LC3-dependent autophagic program. Concomitant with autophagic induction, decorin blunts capillary morphogenesis and endothelial cell migration, thereby significantly compromising tumor angiogenesis. In parallel within the tumor proper, decorin binds multiple RTKs with high affinity, including Met, for a multitude of oncosuppressive functions including growth inhibition, tumor cell …

Proteasome-Mediated Proteolysis Of The Polyglutamine-Expanded Androgen Receptor Is A Late Event In Spinal And Bulbar Muscular Atrophy (Sbma) Pathogenesis., Erin M Heine, Tamar R Berger, Anna Pluciennik, Christopher R Orr, Lori Zboray, Diane E Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Proteolysis of polyglutamine-expanded proteins is thought to be a required step in the pathogenesis of several neurodegenerative diseases. The accepted view for many polyglutamine proteins is that proteolysis of the mutant protein produces a "toxic fragment" that induces neuronal dysfunction and death in a soluble form; toxicity of the fragment is buffered by its incorporation into amyloid-like inclusions. In contrast to this view, we show that, in the polyglutamine disease spinal and bulbar muscular atrophy, proteolysis of the mutant androgen receptor (AR) is a late event. Immunocytochemical and biochemical analyses revealed that the mutant AR aggregates as a full-length protein, …

Nuclear Localization Of Cpi-17, A Protein Phosphatase-1 Inhibitor Protein, Affects Histone H3 Phosphorylation And Corresponds To Proliferation Of Cancer And Smooth Muscle Cells., Masumi Eto, Jason A Kirkbride, Rishika Chugh, Nana Kofi Karikari, Jee In Kim

Department of Molecular Physiology and Biophysics Faculty Papers

CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear …