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2014

Biochemistry

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Articles 1 - 30 of 43

Full-Text Articles in Cell Biology

Understanding Ten-Eleven Translocation-2 In Hematological And Nervous Systems, Feng Pan Dec 2014

Understanding Ten-Eleven Translocation-2 In Hematological And Nervous Systems, Feng Pan

FIU Electronic Theses and Dissertations

I proposed the study of two distinct aspects of Ten-Eleven Translocation 2 (TET2) protein for understanding specific functions in different body systems.

In Part I, I characterized the molecular mechanisms of Tet2 in the hematological system. As the second member of Ten-Eleven Translocation protein family, TET2 is frequently mutated in leukemic patients. Previous studies have shown that the TET2 mutations frequently occur in 20% myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN), 10% T-cell lymphoma leukemia and 2% B-cell lymphoma leukemia. Genetic mouse models also display distinct phenotypes of various types of hematological malignancies. I performed 5-hydroxymethylcytosine (5hmC) chromatin immunoprecipitation sequencing (ChIP-Seq ...


P120-Catenin Regulates Rest And Corest, And Modulates Mouse Embryonic Stem Cell Differentiation, Moonsup Lee Dec 2014

P120-Catenin Regulates Rest And Corest, And Modulates Mouse Embryonic Stem Cell Differentiation, Moonsup Lee

UT GSBS Dissertations and Theses (Open Access)

The canonical-Wnt pathway and beta-catenin have been extensively studied to determine their contributions to stem cell biology, but less is known about p120-catenin in the nuclear compartment. P120 is developmentally required as a consequence of its biochemical and functional interactions with cadherins, small-GTPases and transcriptional regulators. We report here that p120-catenin binds to and negatively regulates REST and CoREST, that others have indicated form a repressive complex having diverse key roles in developmental and pathologic gene regulation. We thus provide the first evidence for a direct upstream modulator of REST/CoREST function. Using mouse embryonic stem cells (mESCs), mammalian cell ...


Nuclear Transport Of Single Molecules: Dwell Times At The Nuclear Pore Complex, Ulrich Kubitscheck, David Grunwald, Andreas Hoekstra, Daniel Rohleder, Thorsten Kues, Jan Peter Siebrasse, Reiner Peters Nov 2014

Nuclear Transport Of Single Molecules: Dwell Times At The Nuclear Pore Complex, Ulrich Kubitscheck, David Grunwald, Andreas Hoekstra, Daniel Rohleder, Thorsten Kues, Jan Peter Siebrasse, Reiner Peters

David Grünwald

The mechanism by which macromolecules are selectively translocated through the nuclear pore complex (NPC) is still essentially unresolved. Single molecule methods can provide unique information on topographic properties and kinetic processes of asynchronous supramolecular assemblies with excellent spatial and time resolution. Here, single-molecule far-field fluorescence microscopy was applied to the NPC of permeabilized cells. The nucleoporin Nup358 could be localized at a distance of 70 nm from POM121-GFP along the NPC axis. Binding sites of NTF2, the transport receptor of RanGDP, were observed in cytoplasmic filaments and central framework, but not nucleoplasmic filaments of the NPC. The dwell times of ...


Intranuclear Binding Kinetics And Mobility Of Single Native U1 Snrnp Particles In Living Cells, David Grunwald, Beatrice Spottke, Volker Buschmann, Ulrich Kubitscheck Nov 2014

Intranuclear Binding Kinetics And Mobility Of Single Native U1 Snrnp Particles In Living Cells, David Grunwald, Beatrice Spottke, Volker Buschmann, Ulrich Kubitscheck

David Grünwald

Uridine-rich small nuclear ribonucleoproteins (U snRNPs) are splicing factors, which are diffusely distributed in the nucleoplasm and also concentrated in nuclear speckles. Fluorescently labeled, native U1 snRNPs were microinjected into the cytoplasm of living HeLa cells. After nuclear import single U1 snRNPs could be visualized and tracked at a spatial precision of 30 nm at a frame rate of 200 Hz employing a custom-built microscope with single-molecule sensitivity. The single-particle tracks revealed that most U1 snRNPs were bound to specific intranuclear sites, many of those presumably representing pre-mRNA splicing sites. The dissociation kinetics from these sites showed a multiexponential decay ...


Autonomy And Robustness Of Translocation Through The Nuclear Pore Complex: A Single-Molecule Study, Thomas Dange, David Grunwald, Antje Grunwald, Reiner Peters, Ulrich Kubitscheck Nov 2014

Autonomy And Robustness Of Translocation Through The Nuclear Pore Complex: A Single-Molecule Study, Thomas Dange, David Grunwald, Antje Grunwald, Reiner Peters, Ulrich Kubitscheck

David Grünwald

All molecular traffic between nucleus and cytoplasm occurs via the nuclear pore complex (NPC) within the nuclear envelope. In this study we analyzed the interactions of the nuclear transport receptors kapalpha2, kapbeta1, kapbeta1DeltaN44, and kapbeta2, and the model transport substrate, BSA-NLS, with NPCs to determine binding sites and kinetics using single-molecule microscopy in living cells. Recombinant transport receptors and BSA-NLS were fluorescently labeled by AlexaFluor 488, and microinjected into the cytoplasm of living HeLa cells expressing POM121-GFP as a nuclear pore marker. After bleaching the dominant GFP fluorescence the interactions of the microinjected molecules could be studied using video microscopy ...


Nuclear Pore Component Nup98 Is A Potential Tumor Suppressor And Regulates Posttranscriptional Expression Of Select P53 Target Genes, Stephan Singer, Ruiying Zhao, Anthony M. Barsotti, Anette Ouwehand, Mina Fazollahi, Elias Coutavas, Kai Breuhahn, Olaf Neumann, Thomas Longerich, Tobias Pusterla, Maureen A. Powers, Keith M. Giles, Peter J. Leedman, Jochen Hess, David Grunwald, Harmen J. Bussemaker, Robert H. Singer, Peter Schirmacher, Carol Prives Nov 2014

Nuclear Pore Component Nup98 Is A Potential Tumor Suppressor And Regulates Posttranscriptional Expression Of Select P53 Target Genes, Stephan Singer, Ruiying Zhao, Anthony M. Barsotti, Anette Ouwehand, Mina Fazollahi, Elias Coutavas, Kai Breuhahn, Olaf Neumann, Thomas Longerich, Tobias Pusterla, Maureen A. Powers, Keith M. Giles, Peter J. Leedman, Jochen Hess, David Grunwald, Harmen J. Bussemaker, Robert H. Singer, Peter Schirmacher, Carol Prives

David Grünwald

The p53 tumor suppressor utilizes multiple mechanisms to selectively regulate its myriad target genes, which in turn mediate diverse cellular processes. Here, using conventional and single-molecule mRNA analyses, we demonstrate that the nucleoporin Nup98 is required for full expression of p21, a key effector of the p53 pathway, but not several other p53 target genes. Nup98 regulates p21 mRNA levels by a posttranscriptional mechanism in which a complex containing Nup98 and the p21 mRNA 3'UTR protects p21 mRNA from degradation by the exosome. An in silico approach revealed another p53 target (14-3-3sigma) to be similarly regulated by Nup98. The ...


Quantitative Analysis Of App Axonal Transport In Neurons: Role Of Jip1 In Enhanced App Anterograde Transport, Kyoko Chiba, Masahiko Araseki, Keisuke Nozawa, Keiko Furukori, Yoichi Araki, Takahide Matsushima, Tadashi Nakaya, Saori Hata, Yuhki Saito, Seiichi Uchida, Yasushi Okada, Angus C. Nairn, Roger J. Davis, Tohru Yamamoto, Masataka Kinjo, Hidenori Taru, Toshiharu Suzuki Nov 2014

Quantitative Analysis Of App Axonal Transport In Neurons: Role Of Jip1 In Enhanced App Anterograde Transport, Kyoko Chiba, Masahiko Araseki, Keisuke Nozawa, Keiko Furukori, Yoichi Araki, Takahide Matsushima, Tadashi Nakaya, Saori Hata, Yuhki Saito, Seiichi Uchida, Yasushi Okada, Angus C. Nairn, Roger J. Davis, Tohru Yamamoto, Masataka Kinjo, Hidenori Taru, Toshiharu Suzuki

Davis Lab Publications

Alzheimer's beta-amyloid precursor protein (APP) associates with kinesin-1 via JNK-interacting protein 1 (JIP1); however, the role of JIP1 in APP transport by kinesin-1 in neurons remains unclear. We performed a quantitative analysis to understand the role of JIP1 in APP axonal transport. In JIP1-deficient neurons, we find that both the fast velocity ( approximately 2.7 mum/s) and high frequency (66%) of anterograde transport of APP cargo are impaired to a reduced velocity ( approximately 1.83 mum/s) and a lower frequency (45%). We identified two novel elements linked to JIP1 function, located in the central region of JIP1b ...


Reassessment Of The Role Of Tsc, Mtorc1 And Micrornas In Amino Acids-Meditated Translational Control Of Top Mrnas, Ilona Patursky-Polischuk, Judith Kasir, Rachel Miloslavski, Zvi Hayouka, Mirit Hausner-Hanochi, Miri Stolovich-Rain, Pinchas Tsukerman, Moshe Biton, Rajini R. Mudhasani, Stephen N. Jones, Oded Meyuhas Oct 2014

Reassessment Of The Role Of Tsc, Mtorc1 And Micrornas In Amino Acids-Meditated Translational Control Of Top Mrnas, Ilona Patursky-Polischuk, Judith Kasir, Rachel Miloslavski, Zvi Hayouka, Mirit Hausner-Hanochi, Miri Stolovich-Rain, Pinchas Tsukerman, Moshe Biton, Rajini R. Mudhasani, Stephen N. Jones, Oded Meyuhas

Open Access Articles

TOP mRNAs encode components of the translational apparatus, and repression of their translation comprises one mechanism, by which cells encountering amino acid deprivation downregulate the biosynthesis of the protein synthesis machinery. This mode of regulation involves TSC as knockout of TSC1 or TSC2 rescued TOP mRNAs translation in amino acid-starved cells. The involvement of mTOR in translational control of TOP mRNAs is demonstrated by the ability of constitutively active mTOR to relieve the translational repression of TOP mRNA upon amino acid deprivation. Consistently, knockdown of this kinase as well as its inhibition by pharmacological means blocked amino acid-induced translational activation ...


Regulation Of Cdk1 Activity During The G1/S Transition In S. Cerevisiae Through Specific Cyclin-Substrate Docking: A Dissertation, Samyabrata Bhaduri Oct 2014

Regulation Of Cdk1 Activity During The G1/S Transition In S. Cerevisiae Through Specific Cyclin-Substrate Docking: A Dissertation, Samyabrata Bhaduri

GSBS Dissertations and Theses

Several cell cycle events require specific forms of the cyclin-CDK complexes. It has been known for some time that cyclins not only contribute by activating the CDK but also by choosing substrates and/or specifying the location of the CDK holoenzyme. There are several examples of B-type cyclins identifying certain peptide motifs in their specific substrates through a conserved region in their structure. Such interactions were not known for the G1 class of cyclins, which are instrumental in helping the cell decide whether or not to commit to a new cell cycle, a function that is non-redundant with B-type cylins ...


A Separable Domain Of The P150 Subunit Of Human Chromatin Assembly Factor-1 Promotes Protein And Chromosome Associations With Nucleoli, Corey L. Smith, Timothy D. Matheson, Daniel J. Trombly, Xiaoming Sun, Eric Campeau, Xuemei Han, John R. Yates Iii, Paul D. Kaufman Sep 2014

A Separable Domain Of The P150 Subunit Of Human Chromatin Assembly Factor-1 Promotes Protein And Chromosome Associations With Nucleoli, Corey L. Smith, Timothy D. Matheson, Daniel J. Trombly, Xiaoming Sun, Eric Campeau, Xuemei Han, John R. Yates Iii, Paul D. Kaufman

Program in Gene Function and Expression Publications and Presentations

Chromatin Assembly Factor-1 (CAF-1) is a three-subunit protein complex conserved throughout eukaryotes that deposits histones during DNA synthesis. Here, we present a novel role for the human p150 subunit in regulating nucleolar macromolecular interactions. Acute depletion of p150 causes redistribution of multiple nucleolar proteins and reduces nucleolar association with several repetitive element-containing loci. Notably, a point mutation in a SUMO-interacting motif (SIM) within p150 abolishes nucleolar associations, whereas PCNA or HP1 interaction sites within p150 are not required for these interactions. Additionally, acute depletion of SUMO-2 or the SUMO E2 ligase Ubc9 reduces alpha-satellite DNA association with nucleoli. The nucleolar ...


Experimental Demonstration Of Bindingless Signal Delivery In Human Cells Via Microfluidics, Fang-Tzu Chuang Jul 2014

Experimental Demonstration Of Bindingless Signal Delivery In Human Cells Via Microfluidics, Fang-Tzu Chuang

Fang-Tzu Chuang

The cellular signal transduction is commonly believed to rely on the direct “contact” or “binding” of the participating molecule reaction that depends positively on the corresponding molecule concentrations. In living systems, however, it is somewhat difficult to precisely match the corresponding rapid “binding,” depending on the probability of molecular collision, existing in the cellular receptor-ligand interactions. Thus, a question arises that if there is another mechanism (i.e., bindingless) that could promote this signal communication. According to this hypothesis, we report a cellular model based on the examination of intracellular calcium concentration to explore whether the unidentified signal delivery in ...


Drosophila Sirt2/Mammalian Sirt3 Deacetylates Atp Synthase Beta And Regulates Complex V Activity, Motiur Rahman, Niraj K. Nirala, Alka Singh, Lihua Julie Zhu, Kaori Taguchi, Takeshi Bamba, Eiichiro Fukusaki, Leslie M. Shaw, David G. Lambright, Jairaj K. Acharya, Usha R. Acharya Jul 2014

Drosophila Sirt2/Mammalian Sirt3 Deacetylates Atp Synthase Beta And Regulates Complex V Activity, Motiur Rahman, Niraj K. Nirala, Alka Singh, Lihua Julie Zhu, Kaori Taguchi, Takeshi Bamba, Eiichiro Fukusaki, Leslie M. Shaw, David G. Lambright, Jairaj K. Acharya, Usha R. Acharya

Program in Gene Function and Expression Publications and Presentations

Adenosine triphosphate (ATP) synthase beta, the catalytic subunit of mitochondrial complex V, synthesizes ATP. We show that ATP synthase beta is deacetylated by a human nicotinamide adenine dinucleotide (NAD(+))-dependent protein deacetylase, sirtuin 3, and its Drosophila melanogaster homologue, dSirt2. dsirt2 mutant flies displayed increased acetylation of specific Lys residues in ATP synthase beta and decreased complex V activity. Overexpression of dSirt2 increased complex V activity. Substitution of Lys 259 and Lys 480 with Arg in human ATP synthase beta, mimicking deacetylation, increased complex V activity, whereas substitution with Gln, mimicking acetylation, decreased activity. Mass spectrometry and proteomic experiments from ...


Phosphatidic Acid Phospholipase A1 Mediates Er-Golgi Transit Of A Family Of G Protein-Coupled Receptors, Govind Kunduri, Changqing Yuan, Velayoudame Parthibane, Katherine M. Nyswaner, Ritu Kanwar, Kunio Nagashima, Steven G. Britt, Nickita Mehta, Varshika Kotu, Mindy Porterfield, Michael Tiemeyer, Patrick J. Dolph, Usha Acharya, Jairaj K. Acharya Jul 2014

Phosphatidic Acid Phospholipase A1 Mediates Er-Golgi Transit Of A Family Of G Protein-Coupled Receptors, Govind Kunduri, Changqing Yuan, Velayoudame Parthibane, Katherine M. Nyswaner, Ritu Kanwar, Kunio Nagashima, Steven G. Britt, Nickita Mehta, Varshika Kotu, Mindy Porterfield, Michael Tiemeyer, Patrick J. Dolph, Usha Acharya, Jairaj K. Acharya

Program in Gene Function and Expression Publications and Presentations

The coat protein II (COPII)-coated vesicular system transports newly synthesized secretory and membrane proteins from the endoplasmic reticulum (ER) to the Golgi complex. Recruitment of cargo into COPII vesicles requires an interaction of COPII proteins either with the cargo molecules directly or with cargo receptors for anterograde trafficking. We show that cytosolic phosphatidic acid phospholipase A1 (PAPLA1) interacts with COPII protein family members and is required for the transport of Rh1 (rhodopsin 1), an N-glycosylated G protein-coupled receptor (GPCR), from the ER to the Golgi complex. In papla1 mutants, in the absence of transport to the Golgi, Rh1 is ...


Key Residues Of Human Cytoplasmic Protein Tyrosine Phosphatase-A And -B For Substrate Binding And Specificity, Byunghyun Park Jul 2014

Key Residues Of Human Cytoplasmic Protein Tyrosine Phosphatase-A And -B For Substrate Binding And Specificity, Byunghyun Park

Open Access Theses

Reversible tyrosine phosphorylation plays an important role in signaling pathways that are essential for regulating cellular growth, differentiation and metabolism. Moreover, several human diseases such as diabetes, obesity and cancers are associated with the deregulation of protein tyrosine phosphatases (PTPs). Several studies provide evidence that PTPs not only contribute to cellular differentiation, but over-expression of these molecules also leads to transformation of non-transfomed cells as well. Based on these results, designing specific PTP inhibitors may ultimately function as potential therapeutic agents to treat various diseases including cancer, diabetes, and autoimmune diseases. EphA2 is a receptor tyrosine kinase which is hypo-phosphorylated ...


Experimental And Computational Analysis Of The Synucleins, Agatha Munyanyi Jul 2014

Experimental And Computational Analysis Of The Synucleins, Agatha Munyanyi

Theses and Dissertations in Biomedical Sciences

The synuclein proteins α, β and γ which are located in the brain, have been a subject of intense research. Of particular interest is α-synuclein, which is found in misfolded forms in Lewy bodies that are associated with Parkinson's disease. Despite the efforts of researchers across the world, the physiological structure and function of the synucleins remains elusive. In recent years, highly controversial reports by some investigators indicate that in its natural form, α-synuclein exists as a tetramer instead of as an intrinsically unstructured monomer. This dissertation presents results of the experimental and computational analysis of the synucleins. First ...


Cooperative Binding Of The Outer Arm-Docking Complex Underlies The Regular Arrangement Of Outer Arm Dynein In The Axoneme, Mikito Owa, Akane Furuta, Jiro Usukura, Fumio Arisaka, Stephen M. King, George B. Witman, Ritsu Kamiya, Ken-Ichi Wakabayashi Jul 2014

Cooperative Binding Of The Outer Arm-Docking Complex Underlies The Regular Arrangement Of Outer Arm Dynein In The Axoneme, Mikito Owa, Akane Furuta, Jiro Usukura, Fumio Arisaka, Stephen M. King, George B. Witman, Ritsu Kamiya, Ken-Ichi Wakabayashi

Cell and Developmental Biology Publications

Outer arm dynein (OAD) in cilia and flagella is bound to the outer doublet microtubules every 24 nm. Periodic binding of OADs at specific sites is important for efficient cilia/flagella beating; however, the molecular mechanism that specifies OAD arrangement remains elusive. Studies using the green alga Chlamydomonas reinhardtii have shown that the OAD-docking complex (ODA-DC), a heterotrimeric complex present at the OAD base, functions as the OAD docking site on the doublet. We find that the ODA-DC has an ellipsoidal shape approximately 24 nm in length. In mutant axonemes that lack OAD but retain the ODA-DC, ODA-DC molecules are ...


To Protect Or Reject, Mary Munson Jun 2014

To Protect Or Reject, Mary Munson

Open Access Articles

A protein known for its role in dismantling faulty SNARE complexes can also help to maintain complexes that have formed properly during membrane fusion.


Activin Limits Progenitor Capability By Promoting Epithelial Cell Differentiation In The Mammary Gland, Karen A. Dunphy, Thiruppavai Chandrasekaran, Niraj Bhatt, Michelle Chen, Amy L. Roberts, Mary Hagen, D. Joseph Jerry May 2014

Activin Limits Progenitor Capability By Promoting Epithelial Cell Differentiation In The Mammary Gland, Karen A. Dunphy, Thiruppavai Chandrasekaran, Niraj Bhatt, Michelle Chen, Amy L. Roberts, Mary Hagen, D. Joseph Jerry

UMass Center for Clinical and Translational Science Research Retreat

Transforming growth factor beta (TGF-beta) and activin utilize common signaling pathways, via smad2/3 and smad4, to mediate tumor suppression by effecting cell cycle arrest and apoptosis. Differences in temporal expression patterns suggest that each cytokine has specific roles in mammary gland development. Activin is expressed during pregnancy and lactation and is required for branching and lactogenesis, implying a role in mammary gland maturation. In contrast, TGF-beta is expressed during involution during mammary gland regression and functions to re-organize the mammary epithelial content to the non-lactating state. Previously, we found that TGF-beta and activin do share common signaling pathways allowing ...


The Role Of Heparin In Vascular Smooth Muscle Cell Phenotype Modulation, James Bowen May 2014

The Role Of Heparin In Vascular Smooth Muscle Cell Phenotype Modulation, James Bowen

Eckardt Scholars Projects

No abstract provided.


Examining The Functional Consequences Of The Flexibility Of Aminoglycoside Phosphotransferase (3’)-Iiia, Katelyn Dawn Rosendall May 2014

Examining The Functional Consequences Of The Flexibility Of Aminoglycoside Phosphotransferase (3’)-Iiia, Katelyn Dawn Rosendall

Masters Theses

The use of aminoglycoside antibiotics began in 1940 with the discovery of streptomycin. The overuse and misuse of antibiotics has resulted in prevalent cases of antibiotic resistance. The most common source of aminoglycoside resistance is the presence of enzymes that covalently modify the antibiotics at specific locations. One such enzyme, APH(3′)-IIIa [the aminoglycoside phosphotransferase three prime three a] conveys resistance by transferring the γ-phosphate [gamma phosphate] from ATP [adenosine triphosphate] onto the 3′ [three prime] carbon of the aminoglycoside antibiotic sugar ring. APH(3′)-IIIa has been shown to be flexible in solution and this flexibility is proposed ...


Functional Analysis Of Cytosolic Hsp70 Nucleotide Exchange Factor Networks In Yeast, Jennifer Lynn Abrams May 2014

Functional Analysis Of Cytosolic Hsp70 Nucleotide Exchange Factor Networks In Yeast, Jennifer Lynn Abrams

UT GSBS Dissertations and Theses (Open Access)

The Hsp70 class of molecular chaperones play critical roles in protein homeostasis via an ATP-dependent folding cycle. Cytosolic Hsp70s in the budding yeast Saccharomyces cerevisiae, Ssa and Ssb, interact with up to three distinct nucleotide exchange factors (NEFs) homologous to human counterparts; Sse1/Sse2/HSP110, Fes1/HspBP1, and Snl1/Bag1. In an effort to understand the differential functional contributions of the cytosolic NEFs to protein homeostasis (“proteostasis”), I carried out comparative genetic, biochemical and cell biological analyses. For these studies, I developed protocols to monitor protein disaggregation and reactivation in a near real-time coupled assay that revealed the importance of ...


Molecular Chaperone Tools For Use Against Neurodegenerative Diseases, Matthew Tinkham May 2014

Molecular Chaperone Tools For Use Against Neurodegenerative Diseases, Matthew Tinkham

Senior Honors Projects

A noted characteristic found in several neurodegenerative disorders, including Alzheimer’s Disease, Parkinson’s Disease, Huntington’s Disease and bovine spongiform encephalopathy, is the accumulation of amyloid plaques in the brain. Amyloid plaques contain deposits of fibrillar aggregates of misfolded proteins that disrupt normal functionality in neurons. Certain variants of these misfolded proteins are self-replicating; these self-replicating amyloids are termed prions (for infectious protein). We are interested in how protein misfolding contributes to amyloid formation and how molecular chaperone proteins can change the formation of amyloid deposits. Chaperone proteins function by catalyzing the proper folding of other proteins, the refolding ...


Defining The Sites Of Interaction Of The Fancd2, Fance, And Fancl Proteins, Joseph Mcclanaghan May 2014

Defining The Sites Of Interaction Of The Fancd2, Fance, And Fancl Proteins, Joseph Mcclanaghan

Senior Honors Projects

Fanconi anemia (FA) is a rare genetic disease characterized by congenital defects, bone marrow failure and increased cancer susceptibility. FA is caused by mutations in any one of 16 genes. These genes encode for proteins that function in the FA-BRCA pathway to repair damaged DNA. Because of its important r­­­ole in DNA repair, this pathway is considered a major cellular tumor suppressor pathway, i.e. is critical for the prevention of cancer. Underscoring this fact, several of the FA genes - including BRCA2, BRIP1, PALB2, and RAD51C - are bona fide breast and ovarian cancer susceptibility genes.

My project involves studying ...


Phthalates And Phthalate Alternatives: Effects On Proliferative And Estrogenic Target Genes In Ishikawa Cells, Ranjani Sundar '15, Ping Yin, Serdar E. Bulun May 2014

Phthalates And Phthalate Alternatives: Effects On Proliferative And Estrogenic Target Genes In Ishikawa Cells, Ranjani Sundar '15, Ping Yin, Serdar E. Bulun

Student Publications & Research

Phthalates are used as plasticizers in many of the products found in medical, household, and industrial applications. Much research has not been completed on the effects of these phthalates as potential endocrine disrupting chemicals (EDCs). As these chemicals are ingested, the mechanism by which they affect the reproductive system is largely unknown. The purpose of this study was to observe how 2 phthalates, Di-n-butyl phthalate (DBP) and Diisononyl phthalate (DINP), and 2 phthalate alternatives, Dioctyl terephthalate (DOTP) and BHT (butylated hydroxytoluene)affect uterine cells in comparison to a vehicle treatment and 17β-Estradiol treatment. Changes in expression of mRNA were observed ...


Characterization Of Ftsa-Ftsn Interaction During Escherichia Coli Cell Division, Kimberly.Busiek@Gmail.Com K. Busiek May 2014

Characterization Of Ftsa-Ftsn Interaction During Escherichia Coli Cell Division, Kimberly.Busiek@Gmail.Com K. Busiek

UT GSBS Dissertations and Theses (Open Access)

Division of a bacterial cell into two equal daughter cells requires precise assembly and constriction of the division machinery, or divisome. The Escherichia coli divisome includes nearly a dozen essential cell division proteins that assemble at midcell between segregating sister chromosomes. FtsZ, a homolog of eukaryotic tubulin, is the first essential cell division protein to localize at midcell where it polymerizes into a ring-shaped scaffold (Z ring). Establishment of the Z ring is required for recruitment of downstream cell division proteins including FtsA, a cytoplasmic protein that tethers the Z ring to the inner membrane. Following localization of FtsA and ...


Angiomotins Link F-Actin Architecture To Hippo Pathway Signaling, Sebastian Mana-Capelli, Murugan Paramasivam, Shubham Dutta, Dannel Mccollum May 2014

Angiomotins Link F-Actin Architecture To Hippo Pathway Signaling, Sebastian Mana-Capelli, Murugan Paramasivam, Shubham Dutta, Dannel Mccollum

GSBS Student Publications

The Hippo pathway regulates the transcriptional coactivator YAP to control cell proliferation, organ size, and stem cell maintenance. Multiple factors, such as substrate stiffness, cell density, and G protein-coupled receptor signaling, regulate YAP through their effects on the F-actin cytoskeleton, although the mechanism is not known. Here we show that angiomotin proteins (AMOT130, AMOTL1, and AMOTL2) connect F-actin architecture to YAP regulation. First, we show that angiomotins are required to relocalize YAP to the cytoplasm in response to various manipulations that perturb the actin cytoskeleton. Second, angiomotins associate with F-actin through a conserved F-actin-binding domain, and mutants defective for F-actin ...


Mnk2 Alternative Splicing Modulates The P38-Mapk Pathway And Impacts Ras-Induced Transformation, Avraham Maimon, Maxim Mogilevsky, Asaf Shilo, Regina Golan-Gerstl, Akram Obiedat, Vered Ben-Hur, Ilana Lebenthal-Loinger, Ilan Stein, Reuven Reich, Jonah Beenstock, Eldar Zehorai, Claus L. Andersen, Kasper Thorsen, Torben F. Orntoft, Roger J. Davis, Ben Davidson, David Mu, Rotem Karni Apr 2014

Mnk2 Alternative Splicing Modulates The P38-Mapk Pathway And Impacts Ras-Induced Transformation, Avraham Maimon, Maxim Mogilevsky, Asaf Shilo, Regina Golan-Gerstl, Akram Obiedat, Vered Ben-Hur, Ilana Lebenthal-Loinger, Ilan Stein, Reuven Reich, Jonah Beenstock, Eldar Zehorai, Claus L. Andersen, Kasper Thorsen, Torben F. Orntoft, Roger J. Davis, Ben Davidson, David Mu, Rotem Karni

Davis Lab Publications

The kinase Mnk2 is a substrate of the MAPK pathway and phosphorylates the translation initiation factor eIF4E. In humans, MKNK2, the gene encoding for Mnk2, is alternatively spliced yielding two splicing isoforms with differing last exons: Mnk2a, which contains a MAPK-binding domain, and Mnk2b, which lacks it. We found that the Mnk2a isoform is downregulated in breast, lung, and colon tumors and is tumor suppressive. Mnk2a directly interacts with, phosphorylates, activates, and translocates p38alpha-MAPK into the nucleus, leading to activation of its target genes, increasing cell death and suppression of Ras-induced transformation. Alternatively, Mnk2b is pro-oncogenic and does not activate ...


Exploration Of Mutations In Erythroid 5-Aminolevulinate Synthase That Lead To Increased Porphyrin Synthesis, Erica Jean Fratz Mar 2014

Exploration Of Mutations In Erythroid 5-Aminolevulinate Synthase That Lead To Increased Porphyrin Synthesis, Erica Jean Fratz

Graduate Theses and Dissertations

5-Aminolevulinate synthase (ALAS; EC 2.3.1.37) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes the first committed step of heme biosynthesis in animals, the condensation of glycine and succinyl-CoA yielding 5-aminolevuliante (ALA), CoA, and CO2. Murine erythroid-specific ALAS (mALAS2) variants that cause high levels of PPIX accumulation provide a new means of targeted, and potentially enhanced, photosensitization. Transfection of HeLa cells with expression plasmids for mALAS2 variants, specifically for those with mutated mitochondrial presequences and a mutation in the active site loop, caused significant cellular accumulation of PPIX, particularly in the membrane. Light treatment of HeLa ...


Ceramide Transfer Protein Deficiency Compromises Organelle Function And Leads To Senescence In Primary Cells, Raghavendra Pralhada Rao, Luana Scheffer, Sargur M. Srideshikan, Velayoudame Parthibane, Teresa Kosakowska-Cholody, M. Athar Masood, Kunio Nagashima, Prabhakar Gudla, Stephen Lockett, Usha Acharya, Jairaj K. Acharya Mar 2014

Ceramide Transfer Protein Deficiency Compromises Organelle Function And Leads To Senescence In Primary Cells, Raghavendra Pralhada Rao, Luana Scheffer, Sargur M. Srideshikan, Velayoudame Parthibane, Teresa Kosakowska-Cholody, M. Athar Masood, Kunio Nagashima, Prabhakar Gudla, Stephen Lockett, Usha Acharya, Jairaj K. Acharya

Program in Gene Function and Expression Publications and Presentations

Ceramide transfer protein (CERT) transfers ceramide from the endoplasmic reticulum (ER) to the Golgi complex. Its deficiency in mouse leads to embryonic death at E11.5. CERT deficient embryos die from cardiac failure due to defective organogenesis, but not due to ceramide induced apoptotic or necrotic cell death. In the current study we examined the effect of CERT deficiency in a primary cell line, namely, mouse embryonic fibroblasts (MEFs). We show that in MEFs, unlike in mutant embryos, lack of CERT does not lead to increased ceramide but causes an accumulation of hexosylceramides. Nevertheless, the defects due to defective sphingolipid ...


A Kras-Directed Transcriptional Silencing Pathway That Mediates The Cpg Island Methylator Phenotype, Ryan W. Serra, Minggang Fang, Sung Mi Park, Lloyd Hutchinson, Michael R. Green Mar 2014

A Kras-Directed Transcriptional Silencing Pathway That Mediates The Cpg Island Methylator Phenotype, Ryan W. Serra, Minggang Fang, Sung Mi Park, Lloyd Hutchinson, Michael R. Green

Program in Molecular Medicine Publications and Presentations

Approximately 70% of KRAS-positive colorectal cancers (CRCs) have a CpG island methylator phenotype (CIMP) characterized by aberrant DNA hypermethylation and transcriptional silencing of many genes. The factors involved in, and the mechanistic basis of, CIMP is not understood. Among the CIMP genes are the tumor suppressors p14(ARF), p15(INK4B), and p16(INK4A), encoded by the INK4-ARF locus. In this study, we perform an RNA interference screen and identify ZNF304, a zinc-finger DNA-binding protein, as the pivotal factor required for INK4-ARF silencing and CIMP in CRCs containing activated KRAS. In KRAS-positive human CRC cell lines and tumors, ZNF304 is bound ...