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2010

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Full-Text Articles in Life Sciences

Revegetating Burned Arid Lands: Identifying Successful Native Species Using Trait And Competition Analysis: Final Report, Scott R. Abella Dec 2010

Revegetating Burned Arid Lands: Identifying Successful Native Species Using Trait And Competition Analysis: Final Report, Scott R. Abella

Fire Science

Species selection can make the difference between successful revegetation projects and costly failures. Candidate native species for revegetating burned arid lands in the southwestern United States must meet at least two criteria. These species must: (1) be competitive in postfire environments typically dominated by exotic grasses, and (2) be able to become established reliably by seeding or planting. In response to Manager’s Request Task 3 (reestablishment of native vegetation after fires on arid lands) in the 2006 JFS announcement for proposals, this research tackled the problem of selecting native species with the greatest chance of revegetation success by conducting ...


Lake Mead National Recreation Area Sensitive Wildlife Species Monitoring And Analysis: Quarterly Progress Report, Period Ending December 31, 2010, Margaret N. Rees Dec 2010

Lake Mead National Recreation Area Sensitive Wildlife Species Monitoring And Analysis: Quarterly Progress Report, Period Ending December 31, 2010, Margaret N. Rees

Wildlife Monitoring

Project 1. Relict Leopard Frog Monitoring, Management, and Research

  • Final milestones and deliverables for this project were completed this quarter.
  • Fall monitoring surveys were completed at all sites.
  • Habitat actions to improve breeding pools were conducted at one site.
  • Data and associated metadata were compiled and quality assured.
  • Final and annual reports were written and submitted in required formats for Clark County

and the Relict Leopard Frog Conservation Team.

Project 2. Bald Eagle Winter Monitoring and Evaluation

  • This project was previously completed and all associated deliverables met.
  • Efforts were provided this quarter in support of the 2011 winter count.

Project ...


Toll-Like Receptor Signaling In Liver Diseases, Gyongyi Szabo, Timothy R. Billiar, Keigo Machida, Ian Nicholas Crispe, Ekihiro Seki Dec 2010

Toll-Like Receptor Signaling In Liver Diseases, Gyongyi Szabo, Timothy R. Billiar, Keigo Machida, Ian Nicholas Crispe, Ekihiro Seki

Open Access Articles

No abstract provided.


Lamprey Watershed Education And Outreach, Lamprey River Watershed Association, Dawn Genes, Lamprey River Watershed Association. Lamprey River Nominating Committee Dec 2010

Lamprey Watershed Education And Outreach, Lamprey River Watershed Association, Dawn Genes, Lamprey River Watershed Association. Lamprey River Nominating Committee

PREP Reports & Publications

The Lamprey River Nomination Committee sought the assistance of the Piscataqua Region Estuaries Partnership (PREP) to complete an extensive and detailed information package to nominate the Lamprey River and its major tributaries to the NH Rivers Management and Protection Program. The nomination package was due at DES on June 1, 2010, was reviewed and accepted by the State Rivers Management Committee in September and forwarded to the Commissioner of DES. The nomination is now working through the NH legislature with hearings anticipated during the spring 2011 session. If passed, the bill should be signed by Governor Lynch in July of ...


Enhancement Of Reactive Oxygen Species Production And Chlamydial Infection By The Mitochondrial Nod-Like Family Member Nlrx1, Ali A. Abdul-Sater, Najwene Saïd-Sadier, Verissa M. Lam, Bhavni Singh, Matthew A. Pettengill, Fraser Soares, Ivan Tattoli, Simone Lipinski, Stephen E. Girardin, Philip Rosenstiel, David M. Ojcius Dec 2010

Enhancement Of Reactive Oxygen Species Production And Chlamydial Infection By The Mitochondrial Nod-Like Family Member Nlrx1, Ali A. Abdul-Sater, Najwene Saïd-Sadier, Verissa M. Lam, Bhavni Singh, Matthew A. Pettengill, Fraser Soares, Ivan Tattoli, Simone Lipinski, Stephen E. Girardin, Philip Rosenstiel, David M. Ojcius

Dugoni School of Dentistry Faculty Articles

Chlamydia trachomatis infections cause severe and irreversible damage that can lead to infertility and blindness in both males and females. Following infection of epithelial cells, Chlamydia induces production of reactive oxygen species (ROS). Unconventionally, Chlamydiae use ROS to their advantage by activating caspase-1, which contributes to chlamydial growth. NLRX1, a member of the Nod-like receptor family that translocates to the mitochondria, can augment ROS production from the mitochondria following Shigella flexneri infections. However, in general, ROS can also be produced by membrane-bound NADPH oxidases. Given the importance of ROS-induced caspase-1 activation in growth of the chlamydial vacuole, we investigated the ...


Optimization Of Application Of Delactosed Whey Permeate Treatment To Extend The Shelf-Life Of Fresh Cut Tomato Using Response Surface Methodology., Lubna Ahmed, Ana Belen Martin-Diana, Daniel Rico, Catherine Barry-Ryan Dec 2010

Optimization Of Application Of Delactosed Whey Permeate Treatment To Extend The Shelf-Life Of Fresh Cut Tomato Using Response Surface Methodology., Lubna Ahmed, Ana Belen Martin-Diana, Daniel Rico, Catherine Barry-Ryan

Articles

Optimization of delactosed whey permeate (DWP) treatment for fresh-cut tomato was accomplished by evaluating different quality, nutritional and microbial markers. Response surface methodology was applied to obtain polynomial model equations. DWP concentration (0 - 5 %) and storage (0 - 10 days) were used as independent factors in order to optimize the process. The analyses showed that increases in DWP concentration extended the quality of the fresh-cut tomato significantly (p3 % were scored unacceptable by the sensory panel due to perceived off-odours. DWP treatment also improved retention of ascorbic acid and lycopene over storage. The total aerobic counts and yeast and moulds were reduced ...


Determination Of The Effect Of Dairy Powders On Adherence Of Streptococcus Sobrinus And Streptococcus Salivarius To Hydroxylapatite And Growth Of These Bacteria, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan Dec 2010

Determination Of The Effect Of Dairy Powders On Adherence Of Streptococcus Sobrinus And Streptococcus Salivarius To Hydroxylapatite And Growth Of These Bacteria, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan

Articles

Dental caries is a highly prevalent disease caused by colonisation of tooth surfaces by cariogenic bacteria, such as Streptococcus sobrinus and Streptococcus salivarius. Reducing initial adherence of such bacteria to teeth may delay onset of caries. Many foods, such as milk, can inhibit microbial adherence. In this investigation, the effect of untreated (UT) and enzyme-treated (ET) dairy powders on adherence of S. sobrinus and S. salivarius to hydroxylapatite (HA), an analogue of tooth enamel, was examined. Untreated (UT) acid whey protein concentrate (AWPC) 80 inhibited streptococcal adherence to phosphate-buffered saline-coated HA (PBS-HA) and saliva-coated HA (S-HA) by >80% at ⩾31 ...


Characterization Of The Role Of Nicotine And Delta 9-Thc In Modulation Of Neuroinflammation, Jared Ehrhart Dec 2010

Characterization Of The Role Of Nicotine And Delta 9-Thc In Modulation Of Neuroinflammation, Jared Ehrhart

Graduate Theses and Dissertations

Neuroinflammation is a major driving force in the progression of neurodegenerative disorders. Nicotinic acetylcholine receptors, as well as cannabinoid CB2 receptors, have been shown to have strong anti-inflammatory properties when activated. These effects are shown, in vivo, to be a result of stimulation of α7 nAChRs and CB2 cannabinoid receptors. Microglia cells, an immune cell in the brain, are shown to express both of these receptor subtypes. The studies detailed herein, investigated the ability of two compounds, nicotine and Δ9-THC, in modulation of inflammatory processes. Stimulation of these receptors on microglia using nicotine and Δ9-THC blocked the activation of these ...


Global Patterns And Predictions Of Seafloor Biomass Using Random Forests, Chih-Lin Wei, Gilbert T. Rowe, Elva Escobar-Briones, Antje Boetius, Thomas Soltwedel, M. Julian Caley, Yousria Soliman, Falk Huettmann, Fangyuan Qu, Zishan Yu, C. Roland Pitcher, Richard L. Haedrich, Mary K. Wicksten, Michael A. Rex, Jeffrey G. Baguley, Jyotsna Sharma, Roberto Danovaro, Ian R. Macdonald, Clifton C. Nunnally, Jody W. Deming, Paul Montagna, Mélanie Lévesque, Jan Marcin Weslawski, Maria Wlodarska-Kowalczuk, Baban S. Ingole, Brian J. Bett, David S. M. Billett, Andrew Yool, Bodil A. Bluhm, Katrin Iken, Bhavani E. Narayanaswamy Dec 2010

Global Patterns And Predictions Of Seafloor Biomass Using Random Forests, Chih-Lin Wei, Gilbert T. Rowe, Elva Escobar-Briones, Antje Boetius, Thomas Soltwedel, M. Julian Caley, Yousria Soliman, Falk Huettmann, Fangyuan Qu, Zishan Yu, C. Roland Pitcher, Richard L. Haedrich, Mary K. Wicksten, Michael A. Rex, Jeffrey G. Baguley, Jyotsna Sharma, Roberto Danovaro, Ian R. Macdonald, Clifton C. Nunnally, Jody W. Deming, Paul Montagna, Mélanie Lévesque, Jan Marcin Weslawski, Maria Wlodarska-Kowalczuk, Baban S. Ingole, Brian J. Bett, David S. M. Billett, Andrew Yool, Bodil A. Bluhm, Katrin Iken, Bhavani E. Narayanaswamy

Biology Faculty Publication Series

A comprehensive seafloor biomass and abundance database has been constructed from 24 oceanographic institutions worldwide within the Census of Marine Life (CoML) field projects. The machine-learning algorithm, Random Forests, was employed to model and predict seafloor standing stocks from surface primary production, water-column integrated and export particulate organic matter (POM), seafloor relief, and bottom water properties. The predictive models explain 63% to 88% of stock variance among the major size groups. Individual and composite maps of predicted global seafloor biomass and abundance are generated for bacteria, meiofauna, macrofauna, and megafauna (invertebrates and fishes). Patterns of benthic standing stocks were positive ...


A Study To Minimize Or Eliminate Hardbottom And Reef Impacts From Anchoring Activities In Designated Anchorages At The Ports Of Miami And Palm Beach, Brian K. Walker Dec 2010

A Study To Minimize Or Eliminate Hardbottom And Reef Impacts From Anchoring Activities In Designated Anchorages At The Ports Of Miami And Palm Beach, Brian K. Walker

Marine & Environmental Sciences Faculty Reports

No abstract provided.


Conjugated Polymer Nanoparticles For Effective Sirna Delivery To Tobacco By-2 Protoplasts, Asitha T. Silva, Alien Nguyen, Changming Ye, Jeanmarie Verchot, Joong Ho Moon Dec 2010

Conjugated Polymer Nanoparticles For Effective Sirna Delivery To Tobacco By-2 Protoplasts, Asitha T. Silva, Alien Nguyen, Changming Ye, Jeanmarie Verchot, Joong Ho Moon

Department of Chemistry and Biochemistry

Background

Post transcriptional gene silencing (PTGS) is a mechanism harnessed by plant biologists to knock down gene expression. siRNAs contribute to PTGS that are synthesized from mRNAs or viral RNAs and function to guide cellular endoribonucleases to target mRNAs for degradation. Plant biologists have employed electroporation to deliver artificial siRNAs to plant protoplasts to study gene expression mechanisms at the single cell level. One drawback of electroporation is the extensive loss of viable protoplasts that occurs as a result of the transfection technology.

Results

We employed fluorescent conjugated polymer nanoparticles (CPNs) to deliver siRNAs and knockdown a target gene in ...


Oregon Aspen Project, Forest Restoration Partnership Dec 2010

Oregon Aspen Project, Forest Restoration Partnership

Aspen Bibliography

The Oregon Aspen Project was initiated in response to the decline of aspen groves in Oregon and throughout the Western United States, and the lack of information to guide managers interested in stewardship to enhance this resource. There were three central goals and accompanying objectives for this project which are listed below. The project accomplishments are provided below each bulleted objective


Conclusions About Niche Expansion In Introduced Impatiens Walleriana Populations Depend On Method Of Analysis, Lisa Mandle, Dan L. Warren, Matthias H. Hoffman, A. Townsend Peterson, Johanna Schmitt, Eric J. Von Wettberg Dec 2010

Conclusions About Niche Expansion In Introduced Impatiens Walleriana Populations Depend On Method Of Analysis, Lisa Mandle, Dan L. Warren, Matthias H. Hoffman, A. Townsend Peterson, Johanna Schmitt, Eric J. Von Wettberg

Department of Biological Sciences

Determining the degree to which climate niches are conserved across plant species’ native and introduced ranges is valuable to developing successful strategies to limit the introduction and spread of invasive plants, and also has important ecological and evolutionary implications. Here, we test whether climate niches differ between native and introduced populations of Impatiens walleriana, globally one of the most popular horticultural species. We use approaches based on both raw climate data associated with occurrence points and ecological niche models (ENMs) developed with Maxent. We include comparisons of climate niche breadth in both geographic and environmental spaces, taking into account differences ...


Strategies To Resolve The Three-Dimensional Structure Of The Genome Of Small Single-Stranded Icosahedral Viruses, Eduardo Sanz Garcia Dec 2010

Strategies To Resolve The Three-Dimensional Structure Of The Genome Of Small Single-Stranded Icosahedral Viruses, Eduardo Sanz Garcia

Theses and Dissertations

The aim of this study is the three-dimensional structural characterization of the genome packaging inside viral capsids via cryo-electron microscopy and three-dimensional reconstruction. The genome of some single-stranded viruses can be densely packaged within their capsid shells. Several stretches of the genome are known to adopt stable secondary structures, however, to date, little is known about the three-dimensional organization of the genome inside their capsid shells. Two techniques have been developed to facilitate the structural elucidation of genome packaging: the asymmetric random-model method, and the symmetry-mismatch, random model method. Both techniques were successfully tested with model and experimental data. The ...


The Tax Relief, Unemployment Insurance Reauthorization, And Job Creation Act Of 2010 (H.R. 4853), Neil E. Harl Dec 2010

The Tax Relief, Unemployment Insurance Reauthorization, And Job Creation Act Of 2010 (H.R. 4853), Neil E. Harl

Agricultural Law Digest

Note from the Editor:

This is a special edition of the Agricultural Law Digest published to provide our subscribers with the quickest access to Dr. Harl’s article on the new tax legislation. The article will also be published in the first issue in January 2011 but the issue will include new summaries of current developments.


Biphasic Targeting And Cleavage Furrow Ingression Directed By The Tail Of A Myosin Ii, X. Fang, J. Y. Luo, R. Nishihama, C. Wloka, C. Dravis, M. Travaglia, M. Iwase, Elizabeth Ann Vallen, E. Bi Dec 2010

Biphasic Targeting And Cleavage Furrow Ingression Directed By The Tail Of A Myosin Ii, X. Fang, J. Y. Luo, R. Nishihama, C. Wloka, C. Dravis, M. Travaglia, M. Iwase, Elizabeth Ann Vallen, E. Bi

Biology Faculty Works

Cytokinesis in animal and fungal cells utilizes a contractile actomyosin ring (AMR). However, how myosin II is targeted to the division site and promotes AMR assembly, and how the AMR coordinates with membrane trafficking during cytokinesis, remains poorly understood. Here we show that Myo1 is a two-headed myosin II in Saccharomyces cerevisiae, and that Myo1 localizes to the division site via two distinct targeting signals in its tail that act sequentially during the cell cycle. Before cytokinesis, Myo1 localization depends on the septin-binding protein Bni5. During cytokinesis, Myo1 localization depends on the IQGAP Iqg1. We also show that the Myo1 ...


Northeast Research Station Watertown, South Dakota Annual Progress Report, 2010, Agricultural Experiment Station, Plant Science Department Dec 2010

Northeast Research Station Watertown, South Dakota Annual Progress Report, 2010, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 2010 annual progress report for the Northeast Research Station in Watertown, South Dakota. This report is issued by the South Dakota Agricultural Experiment Station and the South Dakota State University Plant Science Department. This report includes weather data, yield comparisons, crop performance trials, corn trials, soybean trials, winter wheat performance testing, Barley Foliar information, weed and pest control, herbicide demonstrations, canola and flax variety trials and more.


Complexity Through Recombination: From Chemistry To Biology, Niles Lehman, Carolina Diaz Arenas, Wesley A. White, Francis J. Schmidt Dec 2010

Complexity Through Recombination: From Chemistry To Biology, Niles Lehman, Carolina Diaz Arenas, Wesley A. White, Francis J. Schmidt

Chemistry Faculty Publications and Presentations

Recombination is a common event in nature, with examples in physics, chemistry, and biology. This process is characterized by the spontaneous reorganization of structural units to form new entities. Upon reorganization, the complexity of the overall system can change. In particular the components of the system can now experience a new response to externally applied selection criteria, such that the evolutionary trajectory of the system is altered. In this work we explore the link between chemical and biological forms of recombination. We estimate how the net system complexity changes, through analysis of RNA-RNA recombination and by mathematical modeling. Our results ...


Reduction Of Iron (Iii) And Humic Substances Plays A Major Role In Anaerobic Respiration In An Arctic Peat Soil, David A. Lipson, Mony Jha, Ted K. Raab, Walter C. Oechel Dec 2010

Reduction Of Iron (Iii) And Humic Substances Plays A Major Role In Anaerobic Respiration In An Arctic Peat Soil, David A. Lipson, Mony Jha, Ted K. Raab, Walter C. Oechel

Ted K. Raab

Arctic peat soils contain vast reserves of organic C and are largely anaerobic. However, anaerobic respiration, particularly the role of Fe(III) and humic substances as electron acceptors, is not well understood in such ecosystems. We investigated these processes in a drained thaw lake basin on the Arctic coastal plain near Barrow, Alaska. We measured concentrations of soluble Fe and other potential electron acceptors, described the microbial community, and performed experiments in the laboratory and field to measure net rates of Fe(III) reduction and the relationship of this process to C cycling. In most areas within the basin, aerobic ...


Extension Offers Cca Exam Prep Class, Brent A. Pringnitz Dec 2010

Extension Offers Cca Exam Prep Class, Brent A. Pringnitz

Integrated Crop Management News

The Iowa State University Extension Agribusiness Education Program is offering a review session for the upcoming Certified Crop Adviser (CCA) exam. The two-day review session will be held on Jan. 11 from 8:30 a.m. to 5:45 p.m. and Jan. 12 from 8:00 a.m. to 4:00 p.m. in the South Ballroom of the Memorial Union on the Iowa State University campus.


Development Of An In Vivo Rnai Protocol To Investigate Gene Function In The Filarial Nematode, Brugia Malayi, Chuanzhe Song, Jack M. Gallup, Timothy A. Day, Lyric C. Bartholomay, Michael J. Kimber Dec 2010

Development Of An In Vivo Rnai Protocol To Investigate Gene Function In The Filarial Nematode, Brugia Malayi, Chuanzhe Song, Jack M. Gallup, Timothy A. Day, Lyric C. Bartholomay, Michael J. Kimber

Entomology Publications

Our ability to control diseases caused by parasitic nematodes is constrained by a limited portfolio of effective drugs and a paucity of robust tools to investigate parasitic nematode biology. RNA interference (RNAi) is a reverse-genetics tool with great potential to identify novel drug targets and interrogate parasite gene function, but present RNAi protocols for parasitic nematodes, which remove the parasite from the host and execute RNAi in vitro, are unreliable and inconsistent. We have established an alternative in vivo RNAi protocol targeting the filarial nematode Brugia malayi as it develops in an intermediate host, the mosquito Aedes aegypti. Injection of ...


Role For Sumoylation In Systemic Inflammation And Immune Homeostasis In Drosophila Larvae, Indira Paddibhatla, Mark J. Lee, Marta E. Kalamarz, Roberto Ferrarese, Shubha Govind Dec 2010

Role For Sumoylation In Systemic Inflammation And Immune Homeostasis In Drosophila Larvae, Indira Paddibhatla, Mark J. Lee, Marta E. Kalamarz, Roberto Ferrarese, Shubha Govind

Publications and Research

To counter systemic risk of infection by parasitic wasps, Drosophila larvae activate humoral immunity in the fat body and mount a robust cellular response resulting in encapsulation of the wasp egg. Innate immune reactions are tightly regulated and are resolved within hours. To understand the mechanisms underlying activation and resolution of the egg encapsulation response and examine if failure of the latter develops into systemic inflammatory disease, we correlated parasitic wasp-induced changes in the Drosophila larva with systemic chronic conditions in sumoylation-deficient mutants. We have previously reported that loss of either Cactus, the Drosophila (IkB) protein or Ubc9, the SUMO-conjugating ...


Minimum Description Length Measures Of Evidence For Enrichment, Zhenyu Yang, David R. Bickel Dec 2010

Minimum Description Length Measures Of Evidence For Enrichment, Zhenyu Yang, David R. Bickel

COBRA Preprint Series

In order to functionally interpret differentially expressed genes or other discovered features, researchers seek to detect enrichment in the form of overrepresentation of discovered features associated with a biological process. Most enrichment methods treat the p-value as the measure of evidence using a statistical test such as the binomial test, Fisher's exact test or the hypergeometric test. However, the p-value is not interpretable as a measure of evidence apart from adjustments in light of the sample size. As a measure of evidence supporting one hypothesis over the other, the Bayes factor (BF) overcomes this drawback of the p-value but ...


Utilizing Genetically Engineered Mouse Models Of Pancreatic Cancer: Evaluating The Role Of Cathepsin B And The Efficacy Of Farnesyl Thiosalicylic Acid, Aarthi Gopinathan Dec 2010

Utilizing Genetically Engineered Mouse Models Of Pancreatic Cancer: Evaluating The Role Of Cathepsin B And The Efficacy Of Farnesyl Thiosalicylic Acid, Aarthi Gopinathan

Publicly Accessible Penn Dissertations

I have utilized genetically engineered mouse models of pancreatic cancer to identify a potential new therapeutic target, and to test the efficacy of a putative ras inhibitor. In the first part, I show that cathepsin B is upregulated during disease progression in the mouse pancreas, as is overall cathepsin activity. Loss of cathepsin B decreases preinvasive disease burden and imparts a significant survival benefit, with a consistent decrease in proliferation. In addition, lack of cathepsin B also decreases the burden of liver metastasis. Phospho-Erk localization appears to be affected by cathepsin B loss, which may account for the defect in ...


Modeling Virus-Host Networks, James P. Evans Dec 2010

Modeling Virus-Host Networks, James P. Evans

Publicly Accessible Penn Dissertations

Virus-host interactions are being cataloged at an increasing rate using protein interaction assays and small interfering RNA screens for host factors necessary for infection. These interactions can be viewed as a network, where genes or proteins are nodes, and edges correspond to associations between them. Virus-host interac- tion networks will eventually support the study and treatment of infection, but first require more data and better analysis techniques. This dissertation targets these goals with three aims. The first aim tackles the lack of data by providing a method for the computational prediction of virus-host protein interactions. We show that HIV-human protein ...


Vitamin A Metabolism And Commensal Stimulationi In The Promotion Of Mucosal Immunity, Jason A. Hall Dec 2010

Vitamin A Metabolism And Commensal Stimulationi In The Promotion Of Mucosal Immunity, Jason A. Hall

Publicly Accessible Penn Dissertations

The gastrointestinal tract is replete with commensal microbes and dietary nutrients that provide homeostatic signals. Antigen presenting dendritic cells (DC) residing in the underlying lamina propria (Lp) respond to these signals; however, how they contribute to intestinal T cell homeostasis is unclear. In Chapter 2, LpDC are revealed to uniquely induce naïve T cell differentiation into the Foxp3+ regulatory T cell (Treg) subset. Further, the molecular mechanisms controlling this capacity both in vitro and in vivo are shown to hinge on the vitamin A metabolite, retinoic acid (RA), which LpDC are equipped to synthesize, and the cytokine, TGF-beta. T cell ...


The Tumor Suppressor Protein P53 And The Antagonizing Oncoprotein E6 From Human Papillomavirus Type 16, Kimberly A. Malecka Dec 2010

The Tumor Suppressor Protein P53 And The Antagonizing Oncoprotein E6 From Human Papillomavirus Type 16, Kimberly A. Malecka

Publicly Accessible Penn Dissertations

The tumor suppressor protein p53 transactivates genes involved in cell cycle arrest and apoptosis in response to DNA damage, cellular stress and some oncogenic proteins. The wild type polypeptide chain of p53 has four distinct domains, including the sequence specific DNA binding core domain and the C terminal tetramerization domain. p53 must retain its ability to oligomerize and bind DNA targets in vivo to fulfill its function. Using X-ray crystallography and a crosslinking strategy, the structure of a wild type tetrameric p53 core domain bound to its consensus sequence was solved. This structure gives insight into DNA bend, core domain-DNA ...


Mechanisms Of Hdac2 Function In The Regulation Of Adult Cardiac Hypertrophy And Embryonic Myocyte Proliferation, Wenting Zhu Dec 2010

Mechanisms Of Hdac2 Function In The Regulation Of Adult Cardiac Hypertrophy And Embryonic Myocyte Proliferation, Wenting Zhu

Publicly Accessible Penn Dissertations

HDACs can modify the structure and function of chromatin to regulate gene expression and can also modify many non-histone proteins that regulate cell function and signaling. HDACs have attracted increasing interest because they are involved in a variety of physiologic and pathophysiologic processes including stem cell maintenance, differentiation, cancer, inflammation and cardiac diseases. In the absence of Hdac2, mice display myocyte hyper-proliferation during embryonic development and resistance to cardiac hypertrophy in adulthood. This doctoral dissertation examines the function of two Hdac2 downstream targets, Inpp5f and Gata4, in regulating adult cardiac hypertrophy and embryonic myocyte proliferation, respectively. My results suggest that ...


Effect Of Hippocampal Creb Deletion On Models Of Anxiety, Depression, And Antidepressant Response, Brigitta B. Gundersen Dec 2010

Effect Of Hippocampal Creb Deletion On Models Of Anxiety, Depression, And Antidepressant Response, Brigitta B. Gundersen

Publicly Accessible Penn Dissertations

Depression is the most common psychiatric disorder, yet current antidepressants are inadequate as they require weeks of treatment to alleviate symptoms. The mechanism by which the immediate effects of antidepressants cause later behavioral improvements remains unknown, focusing research on downstream signaling events triggered by antidepressant administration. Expression and activity of the transcription factor CREB are increased by antidepressant drugs, and CREB targets include genes known to be involved in antidepressant response. However, the effects of manipulating CREB depend on the brain region examined, with initial studies showing an antidepressant role for CREB in the hippocampus. To investigate the hippocampal-specific importance ...


Circuitry Underlying Sleep In Drosophila Melanogaster: Anatomy And The Role Of Octopamine, Amanda J. Crocker Dec 2010

Circuitry Underlying Sleep In Drosophila Melanogaster: Anatomy And The Role Of Octopamine, Amanda J. Crocker

Publicly Accessible Penn Dissertations

Almost 20 years ago, the gene underlying fatal familial insomnia was discovered, first suggesting the concept that a single gene can regulate sleep. In the two decades since, there have been many advances in the field of behavioral genetics, but it is only in the past 10 years that the genetic analysis of sleep has emerged as an important discipline. Major findings include the discovery of a single gene underlying the sleep disorder narcolepsy, and identification of loci that make quantitative contributions to sleep characteristics. The sleep field has also expanded its focus from mammalian model organisms to Drosophila, zebrafish ...