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Sedimentary Constraints On The Duration Of The Marinoan Oxygen-17 Depletion (Mosd) Event, Bryan A. Killingsworth, Justin A. Hayles, Chuanming Zhou, Huiming Bao Oct 2013

Sedimentary Constraints On The Duration Of The Marinoan Oxygen-17 Depletion (Mosd) Event, Bryan A. Killingsworth, Justin A. Hayles, Chuanming Zhou, Huiming Bao

Faculty Publications

The ∼635 Ma Marinoan glaciation is marked by dramatic Earth system perturbations. Deposition of nonmass-dependently 17Odepleted sulfate (SO42) in worldwide postglacial sediments is, thus far, unique to this glaciation. It is proposed that an extremely high-pCO2 atmosphere can result in highly 17O-depleted atmospheric O2, or the Marinoan Oxygen-17 Depletion (MOSD) event. This anomalous 17O signal was imparted to sulfate of oxidative weathering origin. However, 17O-depleted sulfate occurs in limited sedimentary intervals, suggesting that Earth surface conditions conducive to the MOSD had a finite duration. An MOSD duration can, therefore, provide much needed constraint on modeling Earth system responses at that …

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Streptomyces Coelicolor Encodes A Urate-Responsive Transcriptional Regulator With Homology To Pecs From Plant Pathogens, Hao Huang, Brian J. Mackel, Anne Grove Oct 2013

Streptomyces Coelicolor Encodes A Urate-Responsive Transcriptional Regulator With Homology To Pecs From Plant Pathogens, Hao Huang, Brian J. Mackel, Anne Grove

Faculty Publications

Many transcriptional regulators control gene activity by responding to specific ligands. Members of the multiple-antibiotic resistance regulator (MarR) family of transcriptional regulators feature prominently in this regard, and they frequently function as repressors in the absence of their cognate ligands. Plant pathogens such as Dickeya dadantii encode a MarR homolog named PecS that controls expression of a gene encoding the efflux pump PecM in addition to other virulence genes. We report here that the soil bacterium Streptomyces coelicolor also encodes a PecS homolog (SCO2647) that regulates a pecM gene (SCO2646). S. coelicolor PecS, which exists as a homodimer, binds the …

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Antiviral Rna Silencing Initiated In The Absence Of Rde-4, A Double-Stranded Rna Binding Protein, In Caenorhabditis Elegans, Xunyang Guo, Rui Zhang, Jeffrey Wang, Rui Lu Oct 2013

Antiviral Rna Silencing Initiated In The Absence Of Rde-4, A Double-Stranded Rna Binding Protein, In Caenorhabditis Elegans, Xunyang Guo, Rui Zhang, Jeffrey Wang, Rui Lu

Faculty Publications

Small interfering RNAs (siRNAs) processed from double-stranded RNA (dsRNA) of virus origins mediate potent antiviral defense through a process referred to as RNA interference (RNAi) or RNA silencing in diverse organisms. In the simple invertebrate Caenorhabditis elegans, the RNAi process is initiated by a single Dicer, which partners with the dsRNA binding protein RDE-4 to process dsRNA into viral siRNAs (viRNAs). Notably, in C. elegans this RNA-directed viral immunity (RDVI) also requires a number of worm-specific genes for its full antiviral potential. One such gene is rsd-2 (RNAi spreading defective 2), which was implicated in RDVI in our previous studies. …

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Tunable Cytotoxicity Of Rhodamine 6g Via Anion Variations, Paul K.S. Magut, Susmita Das, Vivian E. Fernand, Jack Losso, Karen Mcdonough, Brittni M. Naylor, Sita Aggarwal, Isiah M. Warner Oct 2013

Tunable Cytotoxicity Of Rhodamine 6g Via Anion Variations, Paul K.S. Magut, Susmita Das, Vivian E. Fernand, Jack Losso, Karen Mcdonough, Brittni M. Naylor, Sita Aggarwal, Isiah M. Warner

Faculty Publications

Chemotherapeutic agents with low toxicity to normal tissues are a major goal in cancer research. In this regard, the therapeutic activities of cationic dyes, such as rhodamine 6G, toward cancer cells have been studied for decades with observed toxicities toward normal and cancer cells. Herein, we report rhodamine 6G-based organic salts with varying counteranions that are stable under physiological conditions, display excellent fluorescence photostability, and more importantly have tunable chemotherapeutic properties. Our in vitro studies indicate that the hydrophobic compounds of this series allow production of nanoparticles which are nontoxic to normal cells and toxic to cancer cells. Furthermore, the …

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Compressed Property Suffix Trees, Wing Kai Hon, Manish Patil, Rahul Shah, Sharma V. Thankachan Oct 2013

Compressed Property Suffix Trees, Wing Kai Hon, Manish Patil, Rahul Shah, Sharma V. Thankachan

Faculty Publications

Property matching is a biologically motivated problem where the task is to find those occurrences of an online pattern P in a string text T (of size n), such that the matched text part satisfies some conceptual property. The property of a string is a set π of (possibly overlapping) intervals {( s1,f1),(s2,f2),.} corresponding to the part of text and an occurrence of a pattern P=T[i,.,(i+|P|-1)] is a valid output only if T[i,.,(i+|P|-1)] is completely contained in at least one interval (sj,fj)â̂̂π. The indexing version of this problem was introduced by A. Amir (2008), where the text is preprocessed in …

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Sensitivity-Enhanced Solid-State Nmr Detection Of Expansin's Target In Plant Cell Walls, Tuo Wang, Yong Bum Park, Marc A. Caporini, Melanie Rosay, Linghao Zhong, Daniel J. Cosgrove, Mei Hong Oct 2013

Sensitivity-Enhanced Solid-State Nmr Detection Of Expansin's Target In Plant Cell Walls, Tuo Wang, Yong Bum Park, Marc A. Caporini, Melanie Rosay, Linghao Zhong, Daniel J. Cosgrove, Mei Hong

Faculty Publications

Structure determination of protein binding to noncrystalline macromolecular assemblies such as plant cell walls (CWs) poses a significant structural biology challenge. CWs are loosened during growth by expansin proteins, which weaken the noncovalent network formed by cellulose, hemicellulose, and pectins, but the CW target of expansins has remained elusive because of the minute amount of the protein required for activity and the complex nature of the CW. Using solid-state NMR spectroscopy, combined with sensitivity-enhancing dynamic nuclear polarization (DNP) and differential isotopic labeling of expansin and polysaccharides, we have now determined the functional binding target of expansin in the Arabidopsis thaliana …

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Variation In One Residue Associated With The Metal Ion-Dependent Adhesion Site Regulates Αiibβ3 Integrin Ligand Binding Affinity, Joel Raborn, Ting Fu, Xue Wu, Zhilong Xiu, Guohui Li, Bing Hao Luo Oct 2013

Variation In One Residue Associated With The Metal Ion-Dependent Adhesion Site Regulates Αiibβ3 Integrin Ligand Binding Affinity, Joel Raborn, Ting Fu, Xue Wu, Zhilong Xiu, Guohui Li, Bing Hao Luo

Faculty Publications

The Asp of the RGD motif of the ligand coordinates with the β I domain metal ion dependent adhesion site (MIDAS) divalent cation, emphasizing the importance of the MIDAS in ligand binding. There appears to be two distinct groups of integrins that differ in their ligand binding affinity and adhesion ability. These differences may be due to a specific residue associated with the MIDAS, particularly the β3 residue Ala252 and corresponding Ala in the β1 integrin compared to the analogous Asp residue in the β2 and β7 integrins. Interestingly, mutations in the adjacent to MIDAS (ADMIDAS) of integrins α4β7 and …

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The Effects Of Hematopoietic Growth Factors On Neurite Outgrowth, Ye Su, Lili Cui, Chunshu Piao, Bin Li, Li Ru Zhao Oct 2013

The Effects Of Hematopoietic Growth Factors On Neurite Outgrowth, Ye Su, Lili Cui, Chunshu Piao, Bin Li, Li Ru Zhao

Faculty Publications

Stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) are initially discovered as the essential hematopoietic growth factors regulating bone marrow stem cell proliferation and differentiation, and SCF in combination with G-CSF (SCF+G-CSF) has synergistic effects on bone marrow stem cell mobilization. In this study we have determined the effect of SCF and G-CSF on neurite outgrowth in rat cortical neurons. Using molecular and cellular biology and live cell imaging approaches, we have revealed that receptors for SCF and G-CSF are expressed on the growth core of cortical neurons, and that SCF+G-CSF synergistically enhances neurite extension through PI3K/AKT and NFκB …

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Ck1 Is Required For A Mitotic Checkpoint That Delays Cytokinesis, Alyssa E. Johnson, Jun Song Chen, Kathleen L. Gould Oct 2013

Ck1 Is Required For A Mitotic Checkpoint That Delays Cytokinesis, Alyssa E. Johnson, Jun Song Chen, Kathleen L. Gould

Faculty Publications

Failure to accurately partition genetic material during cell division causes aneuploidy and drives tumorigenesis [1]. Cell-cycle checkpoints safeguard cells from such catastrophes by impeding cell-cycle progression when mistakes arise. FHA-RING E3 ligases, including human RNF8 [2] and CHFR [3] and fission yeast Dma1 [4], relay checkpoint signals by binding phosphorylated proteins via their FHA domains and promoting ubiquitination of downstream targets [5]. Upon mitotic checkpoint activation, S. pombe Dma1 concentrates at spindle pole bodies (SPBs) in an FHA-dependent manner and ubiquitinates Sid4, a scaffold of Polo kinase, to suspend cytokinesis [6]. However, the kinase or kinases that phosphoprime Sid4 for …

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Chemical Attraction Of Dermacentor Variabilis Ticks Parasitic To Peromyscus Leucopus Based On Host Body Mass And Sex, Tad Dallas, Stephanie Foré Oct 2013

Chemical Attraction Of Dermacentor Variabilis Ticks Parasitic To Peromyscus Leucopus Based On Host Body Mass And Sex, Tad Dallas, Stephanie Foré

Faculty Publications

Macroparasites are commonly aggregated on a small subset of a host population. Previous explanations for this aggregation relate to differences in immunocompetence or the degree to which hosts encounter parasites. We propose active tick host choice through chemical attraction as a potential mechanism leading to aggregated tick burdens. We test this hypothesis using a Y-maze olfactometer, comparing chemical attraction responses of larval and nymphal Dermacentor variabilis ticks parasitic to the white-footed mouse, Peromyscus leucopus, as a function of host sex and host body mass. We hypothesized that larger hosts and male hosts would be most attractive to searching ticks, as …

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Social Descent With Territory Loss Causes Rapid Behavioral, Endocrine And Transcriptional Changes In The Brain, Karen P. Maruska, Lisa Becker, Anoop Neboori, Russell D. Fernald Oct 2013

Social Descent With Territory Loss Causes Rapid Behavioral, Endocrine And Transcriptional Changes In The Brain, Karen P. Maruska, Lisa Becker, Anoop Neboori, Russell D. Fernald

Faculty Publications

In social species that form hierarchies where only dominant males reproduce, lower-ranking individuals may challenge higherranking ones, often resulting in changes in relative social status. How does a losing animal respond to loss of status? Here, using the African cichlid fish Astatotilapia burtoni, we manipulated the social environment, causing males to descend in rank, and then examined changes in behavior, circulating steroids and immediate early gene (IEG) expression (cfos, egr-1) in micro-dissected brain regions as a proxy for neuronal activation. In particular, we examined changes in the conserved 'social behavior network' (SBN), a collection of brain nuclei known to regulate …

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Lsu Research Fall 2013, Louisiana State University And Agricultural & Mechanical College Oct 2013

Lsu Research Fall 2013, Louisiana State University And Agricultural & Mechanical College

Research Magazine

LSU Research is published annually by the Office of Research & Economic Development, Louisiana State University.

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Faculty Senate Newsletter, October 2013, Louisiana State University And Agricultural & Mechanical College Oct 2013

Faculty Senate Newsletter, October 2013, Louisiana State University And Agricultural & Mechanical College

LSU Faculty Senate Publications

Message from President: A new shibboleth among the higher education leadership caste is that the good old days of ample state funding and generous budgets are “never coming back.” Few leaders of American public higher education systems or institutions challenge this seemingly intuitive axiom; none dare risk the loss of legislative or occasionally gubernatorial pity by expressing even a shred of optimism. The embrace of this apparent axiom—the incantation of the gloom-and-doom mantra as a peculiar status symbol indicating sophistication and membership in the highly briefed if not all-knowing leadership in-group—demonstrates the increasing naiveté among the professionalized leadership clique that …

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Silencing Histone Deacetylase-Specific Isoforms Enhances Expression Of Pluripotency Genes In Bovine Fibroblasts, Jaroslaw Staszkiewicz, Rachel A. Power, Lettie L. Harkins, Christian W. Barnes, Karen L. Strickler, Jong S. Rim, Kenneth R. Bondioli, Kenneth J. Eilersten Oct 2013

Silencing Histone Deacetylase-Specific Isoforms Enhances Expression Of Pluripotency Genes In Bovine Fibroblasts, Jaroslaw Staszkiewicz, Rachel A. Power, Lettie L. Harkins, Christian W. Barnes, Karen L. Strickler, Jong S. Rim, Kenneth R. Bondioli, Kenneth J. Eilersten

Faculty Publications

Histone deacetylases (HDACs) catalyze deacetylation of histones that results in altered transcriptional activity. Inhibitors of HDACs have been shown to induce transcriptional changes that contribute positively to reprogramming somatic cells either by nuclear transfer or inducing a pluripotent state. However, the exact molecular mechanisms whereby HDAC inhibitors function and the specificity of the HDAC isoforms in cell reprogramming are not yet fully understood. Herein, we report the ability of individual isoform-specific HDACs to modulate endogenous expression of pluripotency-associated genes in bovine somatic cells. This in vitro study showed that a transient selective depletion of HDACs resulted in elevated mRNA levels …

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Sin-Dependent Phosphoinhibition Of Formin Multimerization Controls Fission Yeast Cytokinesis, K. Adam Bohnert, Agnieszka P. Grzegorzewska, Alaina H. Willet, Craig W. Vander Kooi, David R. Kovar, Kathleen L. Gould Oct 2013

Sin-Dependent Phosphoinhibition Of Formin Multimerization Controls Fission Yeast Cytokinesis, K. Adam Bohnert, Agnieszka P. Grzegorzewska, Alaina H. Willet, Craig W. Vander Kooi, David R. Kovar, Kathleen L. Gould

Faculty Publications

Many eukaryotes accomplish cell division by building and constricting a medial actomyosin-based cytokinetic ring (CR). In Schizosaccharomyces pombe, a Hippo-related signaling pathway termed the septation initiation network (SIN) controls CR formation, maintenance, and constriction. However, how the SIN regulates integral CR components was unknown. Here, we identify the essential cytokinetic formin Cdc12 as a key CR substrate of SIN kinase Sid2. Eliminating Sid2-mediated Cdc12 phosphorylation leads to persistent Cdc12 clustering, which prevents CR assembly in the absence of anillin-like Mid1 and causes CRs to collapse when cytokinesis is delayed. Molecularly, Sid2 phosphorylation of Cdc12 abrogates multimerization of a previously unrecognized …

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Louisiana Agriculture Fall, 2013 Oct 2013

Louisiana Agriculture Fall, 2013

Louisiana Agriculture

No abstract provided.

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Triacylglycerol Mobilization Is Suppressed By Brefeldin A In Chlamydomonas Reinhardtii, Naohiro Kato, Trung Dong, Michael Bailey, Tony Lum, Drury Ingram Oct 2013

Triacylglycerol Mobilization Is Suppressed By Brefeldin A In Chlamydomonas Reinhardtii, Naohiro Kato, Trung Dong, Michael Bailey, Tony Lum, Drury Ingram

Faculty Publications

Brefeldin A suppresses vesicle trafficking by inhibiting exchange of GDP for GTP in ADP-ribosylation factor. We report that brefeldin A suppresses mobilization of triacylglycerols in Chlamydomonas reinhardtii, a model organism of green microalgae. Analyses revealed that brefeldin A causes Chlamydomonas to form lipid droplets in which triacylglycerols accumulate in a dose-dependent manner. Pulse labeling experiment using fluorescent fatty acids suggested that brefeldin A inhibits the cells from degrading fatty acids. The experiment also revealed that the cells transiently form novel compartments that accumulate exogenously added fatty acids in the cytoplasm, designated fatty acid-induced microbodies (FAIMs). Brefeldin A up-regulates the formation …

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Homologous Rig-I-Like Helicase Proteins Direct Rnaimediated Antièiral Immunity In C. Elegans By Distinct Mechanisms, Xunyang Guo, Rui Zhang, Jeffrey Wang, Shou Wei Ding, Rui Lu Oct 2013

Homologous Rig-I-Like Helicase Proteins Direct Rnaimediated Antièiral Immunity In C. Elegans By Distinct Mechanisms, Xunyang Guo, Rui Zhang, Jeffrey Wang, Shou Wei Ding, Rui Lu

Faculty Publications

RNAi-mediated antièiral immunity in Caenorhabditis elegans requires Dicer-related helicase 1 (DRH-1), which encodes the helicase and C-terminal domains homologous to the mammalian retinoic acid inducible gene I (RIG-I)-like helicase (RLH) family of cytosolic immune receptors. Here we show that the antièiral function of DRH-1 requires the RIG-I homologous domains as well as its wormspecific N-terminal domain. We also demonstrate that the helicase and C-terminal domains encoded by either worm DRH-2 or human RIG-I can functionally replace the corresponding domains of DRH-1 to mediate antièiral RNAi in C. elegans. Notably, substitutions in a three-residue motif of the C-terminal regulatory domain of …

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Characterization Of Microsatellites For Population Genetic Analyses Of The Fungus-Growing Termite Odontotermes Formosanus (Isoptera: Termitidae), Claudia Husseneder, Susan P. Garner, Qiuying Huang, Warren Booth, Edward L. Vargo Oct 2013

Characterization Of Microsatellites For Population Genetic Analyses Of The Fungus-Growing Termite Odontotermes Formosanus (Isoptera: Termitidae), Claudia Husseneder, Susan P. Garner, Qiuying Huang, Warren Booth, Edward L. Vargo

Faculty Publications

The fungus-growing subterranean termite Odontotermes formosanus Shiraki (Isoptera: Termitidae) is a destructive pest in Southeast Asia. To facilitate studies on the biology, ecology, and control of O. formosanus, we isolated and characterized nine novel microsatellite loci from a mixed partial genomic library of O. formosanus and the sympatric Macrotermes barneyi Light enriched for di-, tri-, and tetranucleotide repeats. We screened these loci in three populations of O. formosanus from China. All loci were polymorphic. Three loci showed heterozygote deficit possibly because of the presence of null alleles. The remaining six loci with 4-15 alleles per locus and an average observed …

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Two New Species Of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) From Emerald Tree Skinks, Lamprolepis Smaragdina (Lesson) (Sauria: Scincidae) From Papua New Guinea And The Philippines, Chris T. Mcallister, R. Scott Seville, Donald W. Duszynski, Sarah E. Bush, Robert N. Fisher, Christopher C. Austin Oct 2013

Two New Species Of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) From Emerald Tree Skinks, Lamprolepis Smaragdina (Lesson) (Sauria: Scincidae) From Papua New Guinea And The Philippines, Chris T. Mcallister, R. Scott Seville, Donald W. Duszynski, Sarah E. Bush, Robert N. Fisher, Christopher C. Austin

Faculty Publications

Two new species of Eimeria Schneider, 1875, from emerald tree skinks, Lamprolepis smaragdina (Lesson) are described from specimens collected in Papua New Guinea (PNG) and the Philippines. Oöcysts of Eimeria nuiailan n. sp. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bi-layered wall, measure 23.7 × 19.1 μm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal to ellipsoidal, 11.9 × 7.0 μm, L/W 1.7, and the wall is composed of two valves joined by a longitudinal suture; neither …

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Association Of Healthy Aging With Parental Longevity, Sangkyu Kim, David A. Welsh, Katie E. Cherry, Leann Myers, S. Michal Jazwinski Oct 2013

Association Of Healthy Aging With Parental Longevity, Sangkyu Kim, David A. Welsh, Katie E. Cherry, Leann Myers, S. Michal Jazwinski

Faculty Publications

Various measures incorporated in geriatric assessment have found their way into frailty indices (FIs), which have been used as indicators of survival/mortality and longevity. Our goal is to understand the genetic basis of healthy aging to enhance its evidence base and utility. We constructed a FI as a quantitative measure of healthy aging and examined its characteristics and potential for genetic analyses. Two groups were selected from two separate studies. One group (OLLP for offspring of long-lived parents) consisted of unrelated participants at least one of whose parents was age 90 or older, and the other group of unrelated participants …

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The Size Of A Melanin-Based Plumage Ornament Correlates With Glucocorticoid Receptor Concentrations In The Skin Of That Ornament, Christine R. Lattin, L. Michael Romero Sep 2013

The Size Of A Melanin-Based Plumage Ornament Correlates With Glucocorticoid Receptor Concentrations In The Skin Of That Ornament, Christine R. Lattin, L. Michael Romero

Faculty Publications

© 2013 The Author(s) Published by the Royal Society. All rights reserved. Glucocorticoid hormones such as corticosterone (CORT) play crucial roles in many physiological processes. CORT's actions are primarily mediated via binding to two receptors (glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs)) in different target tissues. CORT receptors can be independently regulated from circulating hormone titres, from tissue to tissue and even within different regions of the same tissue type. Increasing evidence has shown relationships between circulating CORT and melaninbased pigmentation in skin and feathers, yet to our knowledge, there have been no studies of CORT receptors in the skin …

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A New Hero Emerges: Another Exceptional Mammalian Spine And Its Potential Adaptive Significance, William T. Stanley, Lynn W. Robbins, Jean M. Malekani, Sylvestre Gambalemoke Mbalitini, Dudu Akaibe Migurimu, Jean Claude Mukinzi, Jan Hulselmans, Vanya Prévot, Erik Verheyen, Rainer Hutterer, Jeffrey B. Doty, Benjamin P. Monroe, Yoshinori J. Nakazawa, Zachary Braden, Darin Carroll, Julian C.Kerbis Peterhans, John M. Bates, Jacob A. Esselstyn Sep 2013

A New Hero Emerges: Another Exceptional Mammalian Spine And Its Potential Adaptive Significance, William T. Stanley, Lynn W. Robbins, Jean M. Malekani, Sylvestre Gambalemoke Mbalitini, Dudu Akaibe Migurimu, Jean Claude Mukinzi, Jan Hulselmans, Vanya Prévot, Erik Verheyen, Rainer Hutterer, Jeffrey B. Doty, Benjamin P. Monroe, Yoshinori J. Nakazawa, Zachary Braden, Darin Carroll, Julian C.Kerbis Peterhans, John M. Bates, Jacob A. Esselstyn

Faculty Publications

The hero shrew's (Scutisorex somereni) massive interlocking lumbar vertebrae represent the most extreme modification of the vertebral column known in mammals. No intermediate form of this remarkable morphology is known, nor is there any convincing theory to explain its functional significance. We document a new species in the heretofore monotypic genus Scutisorex; the new species possesses cranial and vertebral features representing intermediate character states between S. somereni and other shrews. Phylogenetic analyses of DNA sequences support a sister relationship between the new species and S. somereni. While the function of the unusual spine in Scutisorex is unknown, it gives these …

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Ascaroside Activity In Caenorhabditis Elegans Is Highly Dependent On Chemical Structure, Kyle A. Hollister, Elizabeth S. Conner, Xinxing Zhang, Mark Spell, Gary M. Bernard, Pratik Patel, Ana Carolina G.V. De Carvalho, Rebecca A. Butcher, Justin R. Ragains Sep 2013

Ascaroside Activity In Caenorhabditis Elegans Is Highly Dependent On Chemical Structure, Kyle A. Hollister, Elizabeth S. Conner, Xinxing Zhang, Mark Spell, Gary M. Bernard, Pratik Patel, Ana Carolina G.V. De Carvalho, Rebecca A. Butcher, Justin R. Ragains

Faculty Publications

The nematode Caenorhabditis elegans secretes ascarosides, structurally diverse derivatives of the 3,6-dideoxysugar ascarylose, and uses them in chemical communication. At high population densities, specific ascarosides, which are together known as the dauer pheromone, trigger entry into the stress-resistant dauer larval stage. In order to study the structure-activity relationships for the ascarosides, we synthesized a panel of ascarosides and tested them for dauer-inducing activity. This panel includes a number of natural ascarosides that were detected in crude pheromone extract, but as yet have no assigned function, as well as many unnatural ascaroside derivatives. Most of these ascarosides, some of which have …

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Spectroscopic, Computational Modeling And Cytotoxicity Of A Series Of Meso-Phenyl And Meso-Thienyl-Bodipys, Jaime H. Gibbs, Larry T. Robins, Zehua Zhou, Petia Bobadova-Parvanova, Michael Cottam, Gregory T. Mccandless, Frank R. Fronczek, M. Graça H. Vicente Sep 2013

Spectroscopic, Computational Modeling And Cytotoxicity Of A Series Of Meso-Phenyl And Meso-Thienyl-Bodipys, Jaime H. Gibbs, Larry T. Robins, Zehua Zhou, Petia Bobadova-Parvanova, Michael Cottam, Gregory T. Mccandless, Frank R. Fronczek, M. Graça H. Vicente

Faculty Publications

A series of twenty-two BODIPY compounds were synthesized, containing various meso-phenyl and meso-thienyl groups, and their spectroscopic and structural properties were investigated using both experimental and computational methods. Further functionalization of the BODIPY framework via iodination at the 2,6-pyrrolic positions was explored in order to determine the effect of these heavy atoms on the photophysical and cytotoxicity of the meso-aryl-BODIPYs. BODIPYs bearing meso-thienyl substituents showed the largest red-shifted absorptions and emissions and reduced fluorescence quantum yields. The phototoxicity of the BODIPYs in human carcinoma HEp2 cells depends on both the presence of iodines and the nature of the meso-aryl groups. …

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Physical Clustering Of Flc Alleles During Polycomb-Mediated Epigenetic Silencing In Vernalization, Stefanie Rosa, Filomena De Lucia, Joshua S. Mylne, Danling Zhu, Nobuko Ohmido, Ali Pendle, Naohiro Kato, Peter Shaw, Caroline Dean Sep 2013

Physical Clustering Of Flc Alleles During Polycomb-Mediated Epigenetic Silencing In Vernalization, Stefanie Rosa, Filomena De Lucia, Joshua S. Mylne, Danling Zhu, Nobuko Ohmido, Ali Pendle, Naohiro Kato, Peter Shaw, Caroline Dean

Faculty Publications

Vernalization, the promotion of flowering by cold, involves Polycomb-mediated epigenetic silencing of FLOWERING LOCUS C (FLC). Cold progressively promotes cell-autonomous switching to a silenced state. Here, we used live-cell imaging of FLC-lacO to monitor changes in nuclear organization during vernalization. FLC-lacO alleles physically cluster during the cold and generally remain so after plants are returned to warm. Clustering is dependent on the Polycomb trans-factors necessary for establishment of the FLC silenced state but not on LIKE HETEROCHROMATIN PROTEIN 1, which functions to maintain silencing. These data support the view that physical clustering may be a common feature of Polycomb-mediated epigenetic …

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Unleashing The Power Of Meta-Threading For Evolution/Structure-Based Function Inference Of Proteins, Michal Brylinski Sep 2013

Unleashing The Power Of Meta-Threading For Evolution/Structure-Based Function Inference Of Proteins, Michal Brylinski

Faculty Publications

Protein threading is widely used in the prediction of protein structure and the subsequent functional annotation. Most threading approaches employ similar criteria for the template identification for use in both protein structure and function modeling. Using structure similarity alone might result in a high false positive rate in protein function inference, which suggests that selecting functional templates should be subject to a different set of constraints. In this study, we extend the functionality of eThread, a recently developed approach to meta-threading, focusing on the optimal selection of functional templates. We optimized the selection of template proteins to cover a broad …

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Identification Of An Evolutionarily Conserved Cis-Regulatory Element Controlling The Peg3 Imprinted Domain, Michelle M. Thiaville, Hana Kim, Wesley D. Frey, Joomyeong Kim Sep 2013

Identification Of An Evolutionarily Conserved Cis-Regulatory Element Controlling The Peg3 Imprinted Domain, Michelle M. Thiaville, Hana Kim, Wesley D. Frey, Joomyeong Kim

Faculty Publications

The mammalian Peg3 domain harbors more than 20 evolutionarily conserved regions (ECRs) that are spread over the 250-kb genomic interval. The majority of these ECRs are marked with two histone modifications, H3K4me1 and H3K27ac, suggesting potential roles as distant regulatory elements for the transcription of the nearby imprinted genes. In the current study, the chromatin conformation capture (3C) method was utilized to detect potential interactions of these ECRs with the imprinted genes. According to the results, one region, ECR18, located 200-kb upstream of Peg3 interacts with the two promoter regions of Peg3 and Zim2. The observed interaction is most prominent …

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A Review Of Vaccine Approaches For West Nile Virus, Arun V. Iyer, Konstantin G. Kousoulas Sep 2013

A Review Of Vaccine Approaches For West Nile Virus, Arun V. Iyer, Konstantin G. Kousoulas

Faculty Publications

The West Nile virus (WNC) first appeared in North America in 1999. The North American lineages of WNV were characterized by the presence of neuroinvasive and neurovirulent strains causing disease and death in humans, birds and horses. The 2012 WNV season in the United States saw a massive spike in the number of neuroinvasive cases and deaths similar to what was seen in the 2002-2003 season, according to the West Nile virus disease cases and deaths reported to the CDC by year and clinical presentation, 1999-2012, by ArboNET (Arboviral Diseases Branch, Centers for Disease Control and Prevention). In addition, the …

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Induced Plant Defenses, Host-Pathogen Interactions, And Forest Insect Outbreaks, Bret D. Elderd, Brian J. Rehill, Kyle J. Haynes, Greg Dwyer Sep 2013

Induced Plant Defenses, Host-Pathogen Interactions, And Forest Insect Outbreaks, Bret D. Elderd, Brian J. Rehill, Kyle J. Haynes, Greg Dwyer

Faculty Publications

Cyclic outbreaks of defoliating insects devastate forests, but their causes are poorly understood. Outbreak cycles are often assumed to be driven by density-dependent mortality due to natural enemies, because pathogens and predators cause high mortality and because natural-enemy models reproduce fluctuations in defoliation data. The role of induced defenses is in contrast often dismissed, because toxic effects of defenses are often weak and because induced-defense models explain defoliation data no better than naturalenemy models. Natural-enemy models, however, fail to explain gypsy moth outbreaks in North America, in which outbreaks in forests with a higher percentage of oaks have alternated between …

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