Biochemistry, Biophysics, and Structural Biology Commons^™

Mutations In The N-Terminus Of The Mod(Mdg4) Btb Domain Reveal An Unexpected Role Of Mod(Mdg4) In Chromosome Segregation In Female Meiosis, Gwyneth D E Walker, Bruce D. Mckee

Chancellor’s Honors Program Projects

No abstract provided.

Erecta Family Genes Regulate The Shoot Apical Meristem And Organ Formation, Daniel A. Degennaro

Doctoral Dissertations

Plants are sessile and must adjust their organ growth to their environments. A reservoir of stem cells in the shoot apical meristem (SAM) supplies cells for differentiation into organs. The SAM must balance organ production with stem cell maintenance. The ERECTA family (ERfs) encodes the leucine-rich repeat receptor-like kinases ERECTA (ER), ERECTA-LIKE 1 (ERL1), and ERL2. ERf signaling regulates organ initiation and stem cell maintenance. Results presented in this work include the following:

1) WUSCHEL (WUS) and CLAVATA3 (CLV3) make up a negative feedback loop to maintain SAM size. WUS and CLV3 expression localization is critical for …

Circadian Rhythmicity And Neurodevelopment Of Disco And Grim Mutations In Drosophila Melanogaster, John Patrick Story

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

The death gene grim and its pathway for apoptosis has been studied extensively in Drosophila Melanogaster. The effects of grim mutations on circadian neurodevelopment and locomotor assays have yet to be investigated. Mutations in the gene disconnected (disco) has been shown to disrupt the normal development of the circadian circuitry, specifically the small ventro-lateral neurons (s-LNv’s). Which has shown to severely decrease rhythmicity during free-running periods. Alternatively, we have observed an increase in rhythmicity during free-running periods in grim mutations. Our goal is to investigate the neurodevelopment of the circadian circuitry and their associated locomotor activities in these Drosophila mutations.

Investigation For Novel Anti-Apoptotic Factors In The Neurons Of Drosophila Melanogaster, Haylie Rachel Lam

Chancellor’s Honors Program Projects

No abstract provided.

Effects Of Nicotine On The Cyp6a8 Gene Promoter Of Drosophila Melanogaster, Leslie M. Stroud

Chancellor’s Honors Program Projects

No abstract provided.

Tetrameric Photosystem I: From Initial Discovery And Characterization In Chroococcidiopsis Sp. Ts-821 To Exploration Of Its Distribution And Understanding Of Its Significance In Cyanobacteria, Meng Li

Doctoral Dissertations

Photosystem I (PSI) forms trimeric complexes in most characterized cyanobacteria. We had reported the tetrameric form of PSI in the unicellular cyanobacterium, Chroococcidiopsis sp. TS-821 (TS-821). Using Cryo-EM, a 3D model of the PSI tetramer structure at 11.5 [Angstrom] resolution was obtained and a 2D map within the membrane plane of at 6.1 [Angstrom]. In contrast to the three-fold symmetry in trimeric PSI crystal structure from T. elongatus, two different inter-monomer interactions involving PsaLs are found in the PSI tetramer. Phylogenetic analysis based on PsaL protein sequences shows that TS-821 is closely related to heterocyst-forming cyanobacteria. Additionally, this tetrameric …

Calmodulin-Like Protein 38: A Component Of Ribonucleoprotein Particles During Hypoxic Stress Responses In Arabidopsis, Ansul Lokdarshi

Doctoral Dissertations

Waterlogging stress leads to a crisis in energy metabolism and the accumulation of toxic metabolites due to the hypoxic and/or anoxic environment associated with this condition. To respond and adapt to this situation, higher plants employ an integrated genetic program that leads to the induction of anaerobic response polypeptide genes that encode metabolic and signaling proteins involved in altering metabolic flow and other adaptive responses. The study presented here shows that the Arabidopsis thaliana calmodulin-like protein CML38 is calcium sensor protein that serves as a member of the core anaerobic response gene family and is involved in modulating the survival …

Chromatin Insulators: Master Regulators Of The Eukaryotic Genome, Todd Andrew Schoborg

Doctoral Dissertations

Proper organization of the chromatin fiber within the three dimensional space of the eukaryotic nucleus relies on a number of DNA elements and their interacting proteins whose structural and functional consequences exert significant influence on genome behavior. Chromatin insulators are one such example, where it is thought that these elements assist in the formation of higher order chromatin loop structures by mediating long-range contacts between distant sites scattered throughout the genome. Such looping serves a dual role, helping to satisfy both the physical constraints needed to package the linear DNA polymer within the small volume of the nucleus while simultaneously …

The Role Of The Suppressor Of Hairy-Wing Insulator Protein In Chromatin Organization And Expression Of Transposable Elements In Drosophila Melanogaster, Heather Anne Wallace

Doctoral Dissertations

ABSTRACT Chromatin insulators are required for proper temporal and spatial expression of genes in metazoans. Insulators are thought to play an important role in the regulation of gene expression through the formation of higher-order chromatin structures. One of the best characterized insulators is the Drosophila gypsy insulator, which is located in the gypsy retrovirus. Several proteins are required for gypsy insulator function, including Su(Hw), Mod(mdg4), and CP190. In addition to the gypsy insulator, these proteins are located throughout the genome at sites which are thought to correspond to endogenous insulators. Analysis of the distribution of insulator proteins across a region …

Reverse Genetic And Cell Biological Approaches To The Study Of Developmental Functions Of Class Xi Myosin In Arabidopsis Thaliana, Eunsook Park

Doctoral Dissertations

Myosin proteins function as molecular motors that drive the ATP-dependent movement of cellular components along actin filaments. Vascular plants encode two different types of myosin, referred to as class VIII and class XI. Although class XI myosins have been suggested to function in organelle movement and cytoplasmic streaming, little is known about their cellular function in detail.

The Arabidopsis genome encodes 13 class XI myosin genes. The reasons for the relatively large number of myosin XI isoforms present within a single plant species are unknown. To investigate the function of these gene products in the cell, we determined the spatial …

Ppar Agonists Down-Regulate The Expression Of Atp10c Mrna During Adipogenesis, A Peretich, Maria Cekanova Ms, Rndr, Phd, S Hurst, Sj Baek, Madhu Dahr

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

No abstract provided.

Gene Alterations By Peroxisome Proliferator-Activated Receptor Gamma Agonists In Human Colorectal Cancer Cells, Maria Cekanova, X Li, J Yuan, K B. Kim, Seung J. Baek

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear transcription factor that controls the genes involved in metabolism and carcinogenesis. In the present study, we examined the alteration of gene expression in HCT-116 human colorectal cancer cells by PPARgamma agonists: MCC-555 (5 microM), rosiglitazone (5 microM), and 15-deoxy-Delta12,14-prostaglandin J2 (1 microM). The long-oligo microarray data revealed a list of target genes commonly induced (307 genes) and repressed (32 genes) by tested PPARgamma agonists. These genes were analyzed by Onto-Express software and KEGG pathway analysis and revealed that PPARgamma agonists are involved in cell proliferation, focal adhesion, and several signaling pathways. …

Expression Of G-Protein Inwardly Rectifying Potassium Channels (Girks) In Lung Cancer Cell Lines, Howard Plummer 3rd, Madhu Dhar, Maria Cekanova Ms, Rndr, Phd, Hildegard Schuller

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

BACKGROUND: Previous data from our laboratory has indicated that there is a functional link between the beta-adrenergic receptor signaling pathway and the G-protein inwardly rectifying potassium channel (GIRK1) in human breast cancer cell lines. We wanted to determine if GIRK channels were expressed in lung cancers and if a similar link exists in lung cancer. METHODS: GIRK1-4 expression and levels were determined by reverse transcription polymerase chain reaction (RT-PCR) and real-time PCR. GIRK protein levels were determined by western blots and cell proliferation was determined by a 5-bromo-2'-deoxyuridine (BrdU) assay. RESULTS: GIRK1 mRNA was expressed in three of six small …

Expression And Localization Of Estrogen Receptor-Alpha Protein In Normal And Abnormal Term Placentae And Stimulation Of Trophoblast Differentiation By Estradiol, A Bukovsky, Maria Cekanova Ms, Rndr, Phd, Mr Caudle, J Wimalasena, Js Foster, Dc Henley, Rf Elder

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

Estrogens play an important role in the regulation of placental function, and 17-beta-estradiol (E2) production rises eighty fold during human pregnancy. Although term placenta has been found to specifically bind estrogens, cellular localization of estrogen receptor alpha (ER-alpha) in trophoblast remains unclear. We used western blot analysis and immunohistochemistry with h-151 and ID5 monoclonal antibodies to determine the expression and cellular localization of ER-alpha protein in human placentae and cultured trophoblast cells. Western blot analysis revealed a ~65 kDa ER-alpha band in MCF-7 breast carcinoma cells (positive control). A similar band was detected in five normal term placentae exhibiting strong …

Placental Expression Of Estrogen Receptor Beta And Its Hormone Binding Variant – Comparison With Estrogen Receptor Alpha And A Role For Estrogen Receptors In Asymmetric Division And Differentiation Of Estrogen-Dependent Cells, Antonin Bukovsky, Michael R. Caudle, Maria Cekanova Ms, Rndr, Phd, Romaine I. Fernando, Jay Wimalasena, James S. Foster, Donald C. Henley, Robert F. Elder

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

During human pregnancy, the production of 17-beta-estradiol (E2) rises steadily to eighty fold at term, and placenta has been found to specifically bind estrogens. We have recently demonstrated the expression of estrogen receptor alpha (ER-alpha) protein in human placenta and its localization in villous cytotrophoblast (CT), vascular pericytes, and amniotic fibroblasts. In vitro, E2 stimulated development of large syncytiotrophoblast (ST) aggregates. In the present study we utilized ER-beta affinity purified polyclonal (N19:sc6820) and ER-alpha monoclonal (clone h-151) antibodies. Western blot analysis revealed a single ~52 kDa ER-beta band in chorionic villi (CV) protein extracts. In CV, strong cytoplasmic ER-beta immunoreactivity …

Variability Of Placental Expression Of Cyclin E Low Molecular Weight Variants, A Bukovsky, Maria Cekanova Ms, Rndr, Phd, Mr Caudle, J Wimalasena, Js Foster, Ja Keenan, Rf Elder

Faculty Publications and Other Works -- Biochemistry, Cellular and Molecular Biology

No abstract provided.