Digital Commons Network^™

Upregulation Of Defensins In Burn Sheep Small Intestine, Brian J Poindexter, Gordon L Klein, Stephen M Milner, Roger J Bick

Faculty, Staff and Student Publications

OBJECTIVE: The aim of this study was to visualize and localize the sheep antimicrobials, beta-defensins 1, 2, and 3, (SBD-1, SBD-2, SBD-3), sheep neutrophil defensin alpha (SNP-1), and the cathelicidin LL-37 in sheep small intestine after burn injury, our hypothesis being that these compounds would be upregulated in an effort to overcome a compromised endothelial lining. Response to burn injury includes the release of proinflammatory cytokines and systemic immune suppression that, if untreated, can progress to multiple organ failure and death, so protective mechanisms have to be initiated and implemented.

METHODS: Tissue sections were probed with antibodies to the antimicrobials …

Structure Altering Effects Of A Multicomponent Reading Intervention: An Application Of The Direct And Inferential Mediation (Dime) Model Of Reading Comprehension In Upper Elementary Grades, Georgios Kalantzis, Harel Z Shouval

Faculty, Staff and Student Publications

BACKGROUND: Synaptic plasticity underlies many aspect of learning memory and development. The properties of synaptic plasticity can change as a function of previous plasticity and previous activation of synapses, a phenomenon called metaplasticity. Synaptic plasticity not only changes the functional connectivity between neurons but in some cases produces a structural change in synaptic spines; a change thought to form a basis for this observed plasticity. Here we examine to what extent structural plasticity of spines can be a cause for metaplasticity. This study is motivated by the observation that structural changes in spines are likely to affect the calcium dynamics …

Molluscan Memory Of Injury: Evolutionary Insights Into Chronic Pain And Neurological Disorders, Edgar T Walters, Leonid L Moroz

Faculty, Staff and Student Publications

Molluscan preparations have yielded seminal discoveries in neuroscience, but the experimental advantages of this group have not, until now, been complemented by adequate molecular or genomic information for comparisons to genetically defined model organisms in other phyla. The recent sequencing of the transcriptome and genome of Aplysia californica, however, will enable extensive comparative studies at the molecular level. Among other benefits, this will bring the power of individually identifiable and manipulable neurons to bear upon questions of cellular function for evolutionarily conserved genes associated with clinically important neural dysfunction. Because of the slower rate of gene evolution in this molluscan …

Is Paromomycin An Effective And Safe Treatment Against Cutaneous Leishmaniasis? A Meta-Analysis Of 14 Randomized Controlled Trials, Dae Hyun Kim, Hye Jin Chung, Joachim Bleys, Reza F Ghohestani

Faculty, Staff and Student Publications

BACKGROUND: High cost, poor compliance, and systemic toxicity have limited the use of pentavalent antimony compounds (SbV), the treatment of choice for cutaneous leishmaniasis (CL). Paromomycin (PR) has been developed as an alternative to SbV, but existing data are conflicting.

METHODOLOGY/PRINCIPAL FINDINGS: We searched PubMed, Scopus, and Cochrane Central Register of Controlled Trials, without language restriction, through August 2007, to identify randomized controlled trials that compared the efficacy or safety between PR and placebo or SbV. Primary outcome was clinical cure, defined as complete healing, disappearance, or reepithelialization of all lesions. Data were extracted independently by two investigators, and pooled …

Denaturation And Unfolding Of Human Anaphylatoxin C3a: An Unusually Low Covalent Stability Of Its Native Disulfide Bonds, Jui-Yoa Chang, Curtis C-J Lin, Silvia Salamanca, Michael K Pangburn, Rick A Wetsel

Faculty, Staff and Student Publications

The complement C3a anaphylatoxin is a major molecular mediator of innate immunity. It is a potent activator of mast cells, basophils and eosinophils and causes smooth muscle contraction. Structurally, C3a is a relatively small protein (77 amino acids) comprising a N-terminal domain connected by 3 native disulfide bonds and a helical C-terminal segment. The structural stability of C3a has been investigated here using three different methods: Disulfide scrambling; Differential CD spectroscopy; and Reductive unfolding. Two uncommon features regarding the stability of C3a and the structure of denatured C3a have been observed in this study. (a) There is an unusual disconnection …

Coordinated Changes In Mrna Turnover, Translation, And Rna Processing Bodies In Bronchial Epithelial Cells Following Inflammatory Stimulation, Yuxin Zhai, Zhenping Zhong, Chyi-Ying A Chen, Zhenfang Xia, Ling Song, Michael R Blackburn, Ann-Bin Shyu

Faculty, Staff and Student Publications

Bronchial epithelial cells play a pivotal role in airway inflammation, but little is known about posttranscriptional regulation of mediator gene expression during the inflammatory response in these cells. Here, we show that activation of human bronchial epithelial BEAS-2B cells by proinflammatory cytokines interleukin-4 (IL-4) and tumor necrosis factor alpha (TNF-alpha) leads to an increase in the mRNA stability of the key chemokines monocyte chemotactic protein 1 and IL-8, an elevation of the global translation rate, an increase in the levels of several proteins critical for translation, and a reduction of microRNA-mediated translational repression. Moreover, using the BEAS-2B cell system and …

Extended Kalman Filter For Estimation Of Parameters In Nonlinear State-Space Models Of Biochemical Networks, Xiaodian Sun, Li Jin, Momiao Xiong

Faculty, Staff and Student Publications

It is system dynamics that determines the function of cells, tissues and organisms. to develop mathematical models and estimate their parameters are an essential issue for studying dynamic behaviors of biological systems which include metabolic networks, genetic regulatory networks and signal transduction pathways, under perturbation of external stimuli. In general, biological dynamic systems are partially observed. Therefore, a natural way to model dynamic biological systems is to employ nonlinear state-space equations. Although statistical methods for parameter estimation of linear models in biological dynamic systems have been developed intensively in the recent years, the estimation of both states and parameters of …

Foxm1b Transcriptionally Regulates Vascular Endothelial Growth Factor Expression And Promotes The Angiogenesis And Growth Of Glioma Cells, Yujian Zhang, Nu Zhang, Bingbing Dai, Mingguang Liu, Raymond Sawaya, Keping Xie, Suyun Huang

Faculty, Staff and Student Publications

We previously found that FoxM1B is overexpressed in human glioblastomas and that forced FoxM1B expression in anaplastic astrocytoma cells leads to the formation of highly angiogenic glioblastoma in nude mice. However, the molecular mechanisms by which FoxM1B enhances glioma angiogenesis are currently unknown. In this study, we found that vascular endothelial growth factor (VEGF) is a direct transcriptional target of FoxM1B. FoxM1B overexpression increased VEGF expression, whereas blockade of FoxM1 expression suppressed VEGF expression in glioma cells. Transfection of FoxM1 into glioma cells directly activated the VEGF promoter, and inhibition of FoxM1 expression by FoxM1 siRNA suppressed VEGF promoter activation. …

Rationale For Reading Fluconazole Mics At 24 Hours Rather Than 48 Hours When Testing Candida Spp By The Clsi M27-A2 Standard Method, Luis Ostrosky-Zeichner, John H Rex, Michael A Pfaller, Daniel J Diekema, Barbara D Alexander, David Andes, Steven D Brown, Vishnu Chaturvedi, Mahmoud A Ghannoum, Cindy C Knapp, Daniel J Sheehan, Thomas J Walsh

Faculty, Staff and Student Publications

We investigated if CLSI M27-A2 Candida species breakpoints for fluconazole MIC are valid when read at 24 h. Analysis of a data set showed good correlation between 48- and 24-h MICs, as well as similar outcomes and pharmacodynamic efficacy parameters, except for isolates in the susceptible dose-dependent category, such as Candida glabrata.

Poly(A)-Binding Protein-Interacting Protein 1 Binds To Eukaryotic Translation Initiation Factor 3 To Stimulate Translation, Yvan Martineau, Mélanie C Derry, Xiaoshan Wang, Akiko Yanagiya, Juan José Berlanga, Ann-Bin Shyu, Hiroaki Imataka, Kalle Gehring, Nahum Sonenberg

Faculty, Staff and Student Publications

Poly(A)-binding protein (PABP) stimulates translation initiation by binding simultaneously to the mRNA poly(A) tail and eukaryotic translation initiation factor 4G (eIF4G). PABP activity is regulated by PABP-interacting (Paip) proteins. Paip1 binds PABP and stimulates translation by an unknown mechanism. Here, we describe the interaction between Paip1 and eIF3, which is direct, RNA independent, and mediated via the eIF3g (p44) subunit. Stimulation of translation by Paip1 in vivo was decreased upon deletion of the N-terminal sequence containing the eIF3-binding domain and upon silencing of PABP or several eIF3 subunits. We also show the formation of ternary complexes composed of Paip1-PABP-eIF4G and …

Concept, Design And Implementation Of A Cardiovascular Gene-Centric 50 K Snp Array For Large-Scale Genomic Association Studies, Brendan J. Keating, Sam Tischfield, Sarah S. Murray, Tushar Bhangale, Thomas S. Price, Joseph T. Glessner, Luana Galver, Jeffrey C. Barrett, Struan F A Grant, Deborah N. Farlow, Hareesh R. Chandrupatla, Mark Hansen, Saad Ajmal, George J. Papanicolaou, Yiran Guo, Mingyao Li, Stephanie Derohannessian, Paul I W. De Bakker, Swneke D. Bailey, Alexandre Montpetit, Andrew C. Edmondson, Kent Taylor, Xiaowu Gai, Susanna S. Wang, Myriam Fornage, Tamim Shaikh, Leif Groop, Michael Boehnke, Alistair S. Hall, Andrew T. Hattersley, Edward Frackelton, Nick Patterson, Charleston K W Chiang, Cecelia E. Kim, Richard R. Fabsitz, Willem Ouwehand, Alkes L. Price, Patricia Munroe, Mark Caulfield, Thomas Drake, Eric Boerwinkle, David Reich, A Stephen Whitehead, Thomas P. Cappola, Nilesh J. Samani, A Jake Lusis, Eric Schadt, James G. Wilson, Wolfgang Koenig, Mark I. Mccarthy, Sekar Kathiresan, Stacey B. Gabriel, Hakon Hakonarson, Sonia S. Anand, Muredach Reilly, James C. Engert, Deborah A. Nickerson, Daniel J. Rader, Joel N. Hirschhorn, Garret A. Fitzgerald

Faculty, Staff and Student Publications

A wealth of genetic associations for cardiovascular and metabolic phenotypes in humans has been accumulating over the last decade, in particular a large number of loci derived from recent genome wide association studies (GWAS). True complex disease-associated loci often exert modest effects, so their delineation currently requires integration of diverse phenotypic data from large studies to ensure robust meta-analyses. We have designed a gene-centric 50 K single nucleotide polymorphism (SNP) array to assess potentially relevant loci across a range of cardiovascular, metabolic and inflammatory syndromes. The array utilizes a "cosmopolitan" tagging approach to capture the genetic diversity across approximately 2,000 …

Aggressive Vs Conservative Phototherapy For Infants With Extremely Low Birth Weight, Brenda H Morris, William Oh, Jon E Tyson, David K Stevenson, Dale L Phelps, T Michael O'Shea, Georgia E Mcdavid, Rebecca L Perritt, Krisa P Van Meurs, Betty R Vohr, Cathy Grisby, Qing Yao, Claudia Pedroza, Abhik Das, W Kenneth Poole, Waldemar A Carlo, Shahnaz Duara, Abbot R Laptook, Walid A Salhab, Seetha Shankaran, Brenda B Poindexter, Avroy A Fanaroff, Michele C Walsh, Maynard R Rasmussen, Barbara J Stoll, C Michael Cotten, Edward F Donovan, Richard A Ehrenkranz, Ronnie Guillet, Rosemary D Higgins

Faculty, Staff and Student Publications

BACKGROUND: It is unclear whether aggressive phototherapy to prevent neurotoxic effects of bilirubin benefits or harms infants with extremely low birth weight (1000 g or less).

METHODS: We randomly assigned 1974 infants with extremely low birth weight at 12 to 36 hours of age to undergo either aggressive or conservative phototherapy. The primary outcome was a composite of death or neurodevelopmental impairment determined for 91% of the infants by investigators who were unaware of the treatment assignments.

RESULTS: Aggressive phototherapy, as compared with conservative phototherapy, significantly reduced the mean peak serum bilirubin level (7.0 vs. 9.8 mg per deciliter [120 …

A Schiff Base Connectivity Switch In Sensory Rhodopsin Signaling, Oleg A Sineshchekov, Jun Sasaki, Brian J Phillips, John L Spudich

Faculty, Staff and Student Publications

Sensory rhodopsin I (SRI) in Halobacterium salinarum acts as a receptor for single-quantum attractant and two-quantum repellent phototaxis, transmitting light stimuli via its bound transducer HtrI. Signal-inverting mutations in the SRI-HtrI complex reverse the single-quantum response from attractant to repellent. Fast intramolecular charge movements reported here reveal that the unphotolyzed SRI-HtrI complex exists in two conformational states, which differ by their connection of the retinylidene Schiff base in the SRI photoactive site to inner or outer half-channels. In single-quantum photochemical reactions, the conformer with the Schiff base connected to the cytoplasmic (CP) half-channel generates an attractant signal, whereas the conformer …

Syntaxin 3b Is Essential For The Exocytosis Of Synaptic Vesicles In Ribbon Synapses Of The Retina, Leigh B Curtis, Blair Doneske, Xiaoqin Liu, Christina Thaller, James A Mcnew, Roger Janz

Faculty, Staff and Student Publications

Previous studies have demonstrated that ribbon synapses in the retina do not contain the t-SNARE (target-soluble N-ethylmaleimide-sensitive factor attachment protein receptor) syntaxin 1A that is found in conventional synapses of the nervous system. In contrast, ribbon synapses of the retina contain the related isoform syntaxin 3. In addition to its localization in ribbon synapses, syntaxin 3 is also found in nonneuronal cells, where it has been implicated in the trafficking of transport vesicles to the apical plasma membrane of polarized cells. The syntaxin 3 gene codes for four different splice forms, syntaxins 3A, 3B, 3C, and 3D. We demonstrate here …

The Untapped Power Of "We Don't Know": Epistemological Humility In The Era Of Covid-19, Diasinou Fioravante, Rong-Yu Liu, John H. Byrne

Faculty, Staff and Student Publications

The neuropeptide Phe-Met-Arg-Phe-NH(2) (FMRFa) can induce transcription-dependent long-term synaptic depression (LTD) in Aplysia sensorimotor synapses. We investigated the role of the ubiquitin-proteasome system and the regulation of one of its components, ubiquitin C-terminal hydrolase (ap-uch), in LTD. LTD was sensitive to presynaptic inhibition of the proteasome and was associated with upregulation of ap-uch mRNA and protein. This upregulation appeared to be mediated by CREB2, which is generally regarded as a transcription repressor. Binding of CREB2 to the promoter region of ap-uch was accompanied by histone hyperacetylation, suggesting that CREB2 cannot only inhibit but also promote gene expression. CREB2 was phosphorylated …

Identification And Phenotypic Characterization Of A Second Collagen Adhesin, Scm, And Genome-Based Identification And Analysis Of 13 Other Predicted Mscramms, Including Four Distinct Pilus Loci, In Enterococcus Faecium, Jouko Sillanpää, Sreedhar R Nallapareddy, Vittal P Prakash, Xiang Qin, Magnus Höök, George M Weinstock, Barbara E Murray

Faculty, Staff and Student Publications

Attention has recently been drawn to Enterococcus faecium because of an increasing number of nosocomial infections caused by this species and its resistance to multiple antibacterial agents. However, relatively little is known about the pathogenic determinants of this organism. We have previously identified a cell-wall-anchored collagen adhesin, Acm, produced by some isolates of E. faecium, and a secreted antigen, SagA, exhibiting broad-spectrum binding to extracellular matrix proteins. Here, we analysed the draft genome of strain TX0016 for potential microbial surface components recognizing adhesive matrix molecules (MSCRAMMs). Genome-based bioinformatics identified 22 predicted cell-wall-anchored E. faecium surface proteins (Fms), of which 15 …

Effect Of Progressive Mandibular Advancement On Pharyngeal Airway Size In Anesthetized Adults, Samuel T Kuna, Lee C Woodson, Daneshvari R Solanki, Oliver Esch, Donald E Frantz, Mali Mathru

Faculty, Staff and Student Publications

BACKGROUND: General anesthesia in adult humans is associated with narrowing or complete closure of the pharyngeal airway. The purpose of this study was to determine the effect of progressive mandibular advancement on pharyngeal airway size in normal adults during intravenous infusion of propofol for anesthesia.

METHODS: Magnetic resonance imaging was performed in nine normal adults during wakefulness and during propofol anesthesia. A commercially available intraoral appliance was used to manually advance the mandible. Images were obtained during wakefulness without the appliance and during anesthesia with the participants wearing the appliance under three conditions: without mandibular advancement, advancement to 50% maximum …

Characterization Of The Inflammatory Cells In Ascending Thoracic Aortic Aneurysms In Patients With Marfan Syndrome, Familial Thoracic Aortic Aneurysms, And Sporadic Aneurysms, Rumin He, Dong-Chuan Guo, Wei Sun, Christina L Papke, Senthil Duraisamy, Anthony L Estrera, Hazim J Safi, Chul Ahn, L Maximilian Buja, Frank C Arnett, Jingwu Zhang, Yong-Jian Geng, Dianna M Milewicz

Faculty, Staff and Student Publications

OBJECTIVE: This study sought to characterize the inflammatory infiltrate in ascending thoracic aortic aneurysm in patients with Marfan syndrome, familial thoracic aortic aneurysm, or nonfamilial thoracic aortic aneurysm.

BACKGROUND: Thoracic aortic aneurysms are associated with a pathologic lesion termed "medial degeneration," which is described as a noninflammatory lesion. Thoracic aortic aneurysms are a complication of Marfan syndrome and can be inherited in an autosomal dominant manner of familial thoracic aortic aneurysm.

METHODS: Full aortic segments were collected from patients undergoing elective repair with Marfan syndrome (n = 5), familial thoracic aortic aneurysm (n = 6), and thoracic aortic aneurysms (n …

Molecular And Macromolecular Alterations Of Recombinant Adenoviral Vectors Do Not Resolve Changes In Hepatic Drug Metabolism During Infection, Shellie M Callahan, Piyanuch Wonganan, Maria A Croyle

Faculty, Staff and Student Publications

In this report we test the hypothesis that long-term virus-induced alterations in CYP occur from changes initiated by the virus that may not be related to the immune response. Enzyme activity, protein expression and mRNA of CYP3A2, a correlate of human CYP3A4, and CYP2C11, responsive to inflammatory mediators, were assessed 0.25, 1, 4, and 14 days after administration of several different recombinant adenoviruses at a dose of 5.7 x 1012 virus particles (vp)/kg to male Sprague Dawley rats. Wild type adenovirus, containing all viral genes, suppressed CYP3A2 and 2C11 activity by 37% and 39%, respectively within six hours. Levels fell …

Substance Use Among Persons With Syphilis During Pregnancy — Arizona And Georgia, 2018–2021, Lingpeng Cheng, Qin Fang, Sanket Shah, Ivo C Atanasov, Z Hong Zhou

Faculty, Staff and Student Publications

Grass carp reovirus (GCRV) is a member of the Aquareovirus genus of the family Reoviridae, a large family of double-stranded RNA (dsRNA) viruses infecting plants, insects, fishes and mammals. We report the first subnanometer-resolution three-dimensional structures of both GCRV core and virion by cryoelectron microscopy. These structures have allowed the delineation of interactions among the over 1000 molecules in this enormous macromolecular machine and a detailed comparison with other dsRNA viruses at the secondary-structure level. The GCRV core structure shows that the inner proteins have strong structural similarities with those of orthoreoviruses even at the level of secondary-structure elements, indicating …

Molecular Mechanisms Underlying A Cellular Analog Of Operant Reward Learning, Fred D Lorenzetti, Douglas A Baxter, John H Byrne

Faculty, Staff and Student Publications

Operant conditioning is a ubiquitous but mechanistically poorly understood form of associative learning in which an animal learns the consequences of its behavior. Using a single-cell analog of operant conditioning in neuron B51 of Aplysia, we examined second-messenger pathways engaged by activity and reward and how they may provide a biochemical association underlying operant learning. Conditioning was blocked by Rp-cAMP, a peptide inhibitor of PKA, a PKC inhibitor, and by expressing a dominant-negative isoform of Ca2+-dependent PKC (apl-I). Thus, both PKA and PKC were necessary for operant conditioning. Injection of cAMP into B51 mimicked the effects of operant conditioning. Activation …

Welcome To The Ham-Tmc Library, Vol.22 (1) July - September 2008, Houston Academy Of Medicine-Texas Medical Center Library

Library Lines (1998-2009)

No abstract provided.

Myositis Ossificans Circumscripta Of The Buccinator Muscle: First Report Of A Rare Complication Of Mandibular Third Molar Extraction, Raymond L Wiggins, David Thurber, Kenneth Abramovitch, Jerry Bouquot, Nadarajah Vigneswaran

Faculty, Staff and Student Publications

No abstract provided.

Genetic Variation In Genes For The Xenobiotic-Metabolizing Enzymes Cyp1a1, Ephx1, Gstm1, Gstt1, And Gstp1 And Susceptibility To Colorectal Cancer In Lynch Syndrome, Mala Pande, Christopher I Amos, Daniel R Osterwisch, Jinyun Chen, Patrick M Lynch, Russell Broaddus, Marsha L Frazier

Faculty, Staff and Student Publications

Individuals with Lynch syndrome are predisposed to cancer due to an inherited DNA mismatch repair gene mutation. However, there is significant variability observed in disease expression likely due to the influence of other environmental, lifestyle, or genetic factors. Polymorphisms in genes encoding xenobiotic-metabolizing enzymes may modify cancer risk by influencing the metabolism and clearance of potential carcinogens from the body. In this retrospective analysis, we examined key candidate gene polymorphisms in CYP1A1, EPHX1, GSTT1, GSTM1, and GSTP1 as modifiers of age at onset of colorectal cancer among 257 individuals with Lynch syndrome. We found that subjects heterozygous for CYP1A1 I462V …

A Functional Collagen Adhesin Gene, Acm, In Clinical Isolates Of Enterococcus Faecium Correlates With The Recent Success Of This Emerging Nosocomial Pathogen, Sreedhar R Nallapareddy, Kavindra V Singh, Pablo C Okhuysen, Barbara E Murray

Faculty, Staff and Student Publications

Enterococcus faecium recently evolved from a generally avirulent commensal into a multidrug-resistant health care-associated pathogen causing difficult-to-treat infections, but little is known about the factors responsible for this change. We previously showed that some E. faecium strains express a cell wall-anchored collagen adhesin, Acm. Here we analyzed 90 E. faecium isolates (99% acm(+)) and found that the Acm protein was detected predominantly in clinically derived isolates, while the acm gene was present as a transposon-interrupted pseudogene in 12 of 47 isolates of nonclinical origin. A highly significant association between clinical (versus fecal or food) origin and collagen adherence (P

Contribution Of The Collagen Adhesin Acm To Pathogenesis Of Enterococcus Faecium In Experimental Endocarditis, Sreedhar R Nallapareddy, Kavindra V Singh, Barbara E Murray

Faculty, Staff and Student Publications

Enterococcus faecium is a multidrug-resistant opportunist causing difficult-to-treat nosocomial infections, including endocarditis, but there are no reports experimentally demonstrating E. faecium virulence determinants. Our previous studies showed that some clinical E. faecium isolates produce a cell wall-anchored collagen adhesin, Acm, and that an isogenic acm deletion mutant of the endocarditis-derived strain TX0082 lost collagen adherence. In this study, we show with a rat endocarditis model that TX0082 Deltaacm::cat is highly attenuated versus wild-type TX0082, both in established (72 h) vegetations (P < 0.0001) and for valve colonization 1 and 3 hours after infection (P or=50-fold reduction relative to an Acm producer) were found in three of these five nonadherent isolates, including the sequenced strain TX0016, by quantitative reverse transcription-PCR, indicating that acm transcription is downregulated in vitro in these isolates. However, examination of TX0016 cells obtained directly from infected rat vegetations by flow cytometry showed that Acm was present on 40% of cells grown during infection. Finally, we demonstrated a significant reduction in E. faecium collagen adherence by affinity-purified anti-Acm antibodies from E. faecium endocarditis patient sera, suggesting that Acm may be a potential immunotarget for strategies to control this emerging pathogen.

Spatiotemporally Distributed Frontotemporal Networks For Sentence Reading, Sidney R. Lehky, Xinmiao Peng, Carrie J. Mcadams, Anne B. Sereno

Faculty, Staff and Student Publications

BACKGROUND: A key aspect of representations for object recognition and scene analysis in the ventral visual stream is the spatial frame of reference, be it a viewer-centered, object-centered, or scene-based coordinate system. Coordinate transforms from retinocentric space to other reference frames involve combining neural visual responses with extraretinal postural information.

METHODOLOGY/PRINCIPAL FINDINGS: We examined whether such spatial information is available to anterior inferotemporal (AIT) neurons in the macaque monkey by measuring the effect of eye position on responses to a set of simple 2D shapes. We report, for the first time, a significant eye position effect in over 40% of …

An Sp1/Sp3 Binding Polymorphism Confers Methylation Protection, Yanis A. Boumber, Yutaka Kondo, Xuqi Chen, Lanlan Shen, Yi Guo, Carmen Tellez, Marcos R H Estécio, Saira Ahmed, Jean-Pierre J. Issa

Faculty, Staff and Student Publications

Hundreds of genes show aberrant DNA hypermethylation in cancer, yet little is known about the causes of this hypermethylation. We identified RIL as a frequent methylation target in cancer. In search for factors that influence RIL hypermethylation, we found a 12-bp polymorphic sequence around its transcription start site that creates a long allele. Pyrosequencing of homozygous tumors revealed a 2.1-fold higher methylation for the short alleles (P<0.001). Bisulfite sequencing of cancers heterozygous for RIL showed that the short alleles are 3.1-fold more methylated than the long (P<0.001). The comparison of expression levels between unmethylated long and short EBV-transformed cell lines showed no difference in expression in vivo. Electrophorectic mobility shift assay showed that the inserted region of the long allele binds Sp1 and Sp3 transcription factors, a binding that is absent in the short allele. Transient transfection of RIL allele-specific transgenes showed no effects of the additional Sp1 site on transcription early on. However, stable transfection of methylation-seeded constructs showed gradually decreasing transcription levels from the short allele with eventual spreading of de novo methylation. In contrast, the long allele showed stable levels of expression over time as measured by luciferase and approximately 2-3-fold lower levels of methylation by bisulfite sequencing (P<0.001), suggesting that the polymorphic Sp1 site protects against time-dependent silencing. Our finding demonstrates that, in some genes, hypermethylation in cancer is dictated by protein-DNA interactions at the promoters and provides a novel mechanism by which genetic polymorphisms can influence an epigenetic state.

Activation Of Degp Chaperone-Protease Via Formation Of Large Cage-Like Oligomers Upon Binding To Substrate Proteins, Jiansen Jiang, Xuefeng Zhang, Yong Chen, Yi Wu, Z Hong Zhou, Zengyi Chang, Sen-Fang Sui

Faculty, Staff and Student Publications

Cells use molecular chaperones and proteases to implement the essential quality control mechanism of proteins. The DegP (HtrA) protein, essential for the survival of Escherichia coli cells at elevated temperatures with homologues found in almost all organisms uniquely has both functions. Here we report a mechanism for DegP to activate both functions via formation of large cage-like 12- and 24-mers after binding to substrate proteins. Cryo-electron microscopic and biochemical studies revealed that both oligomers are consistently assembled by blocks of DegP trimers, via pairwise PDZ1-PDZ2 interactions between neighboring trimers. Such interactions simultaneously eliminate the inhibitory effects of the PDZ2 domain. …

Role Of Nono-Histone Interaction In Tnfα-Suppressed Prolyl-4-Hydroxylase Α1, Cheng Zhang, Ming-Xiang Zhang, Ying H Shen, Jared K Burks, Xiao-Nan Li, Scott A Lemaire, Koichi Yoshimura, Hiroki Aoki, Masunori Matsuzaki, Feng-Shuang An, David A Engler, Risë K Matsunami, Joseph S Coselli, Yun Zhang, Xing Li Wang

Faculty, Staff and Student Publications

Inflammation is a key process in cardiovascular diseases. The extracellular matrix (ECM) of the vasculature is a major target of inflammatory cytokines, and TNFalpha regulates ECM metabolism by affecting collagen production. In this study, we have examined the pathways mediating TNFalpha-induced suppression of prolyl-4 hydroxylase alpha1 (P4Halpha1), the rate-limiting isoform of P4H responsible for procollagen hydroxylation, maturation, and organization. Using human aortic smooth muscle cells, we found that TNFalpha activated the MKK4-JNK1 pathway, which induced histone (H) 4 lysine 12 acetylation within the TNFalpha response element in the P4Halpha1 promoter. The acetylated-H4 then recruited a transcription factor, NonO, which, in …