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Full-Text Articles in Biochemistry

A Review Of Rheb Activation Of Mtorc1 And The Great Mystery Of One Missing Gef, Jack Gregory May 2024

A Review Of Rheb Activation Of Mtorc1 And The Great Mystery Of One Missing Gef, Jack Gregory

Senior Honors Theses

The mTORC1 pathway is involved in the regulation of cell growth and translation. The pathway has a complex web of activators and inhibitors to activate mTORC1. mTORC1 is regulated via a small GTPase called Rheb, which interacts directly with mTORC1. This GTPase and its GTPase activating protein (GAP), TSC1/2, have been widely studied to understand how the variety of regulators of mTORC1 interact with these proteins. Despite this, the guanine nucleotide exchange factor (GEF) of Rheb has yet to be identified. This review broadly analyzes Rheb and mTORC1, their structures, regulations, and interactions, and explores the mystery of the missing …


Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker Jul 2023

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …


Methylene Blue Inhibits Cromakalim-Activated K+ Currents In Follicle-Enclosed Oocytes, Dmytro Isaev, Keun-Hang Susan Yang, Georg Petroianu, Dietrich Ernst Lorke, Murat Oz Jan 2023

Methylene Blue Inhibits Cromakalim-Activated K+ Currents In Follicle-Enclosed Oocytes, Dmytro Isaev, Keun-Hang Susan Yang, Georg Petroianu, Dietrich Ernst Lorke, Murat Oz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The effects of methylene blue (MB) on cromakalim-induced K+ currents were investigated in follicle-enclosed Xenopus oocytes. In concentrations ranging from 3–300 μM, MB inhibited K+ currents (IC50: 22.4 μM) activated by cromakalim, which activates KATP channels. MB inhibited cromakalim-activated K+ currents in a noncompetitive and voltage-independent manner. The respective EC50 and slope values for cromakalim-activation of K+ currents were 194 ± 21 µM and 0.91 for controls, and 206 ± 24 µM and 0.87 in the presence of 30 μM MB. The inhibition of cromakalim-induced K+ currents by MB was not …


Generating A Colorimetric Ssa4 Transcript Export Reporter For Multicopy Suppression Screen In S. Cerevisiae, Zaid Hatem Apr 2022

Generating A Colorimetric Ssa4 Transcript Export Reporter For Multicopy Suppression Screen In S. Cerevisiae, Zaid Hatem

Belmont University Research Symposium (BURS)

The export of mRNA from the nucleus to the cytoplasm is a regulatory point that is essential to the pathway of gene expression in eukaryotic cells. The export of mRNA transcripts is mediated through selective doorways called the nuclear pore complexes (NPC). Additionally, there are proteins associated with the nuclear pore complex that assist in facilitating the export. This includes association with the export receptor, Mex67, which binds to the transcript and ferries it through NPCs. During cellular stress, such as heat shock, the export of housekeeping mRNA transcripts is halted, forcing these transcripts to remain inside the nucleus and …


Natural Phaeosphaeride A Derivatives Overcome Drug Resistance Of Tumor Cells And Modulate Signaling Pathways, Victoria Abzianidze, Natalia Moiseeva, Diana Suponina, Sofya Zakharenkova, Nadezhda Rogovskaya, Lidia Laletina, Alvin A. Holder, Denis Krivorotov, Alexander Bogachenkov, Alexander Garabadzhiu, Anton Ukolov, Vyacheslav Kosorukov Mar 2022

Natural Phaeosphaeride A Derivatives Overcome Drug Resistance Of Tumor Cells And Modulate Signaling Pathways, Victoria Abzianidze, Natalia Moiseeva, Diana Suponina, Sofya Zakharenkova, Nadezhda Rogovskaya, Lidia Laletina, Alvin A. Holder, Denis Krivorotov, Alexander Bogachenkov, Alexander Garabadzhiu, Anton Ukolov, Vyacheslav Kosorukov

Chemistry & Biochemistry Faculty Publications

n the present study, natural phaeosphaeride A (PPA) derivatives are synthesized. Anti-tumor studies are carried out on the PC3, K562, HCT-116, THP-1, MCF-7, A549, NCI-H929, Jurkat, and RPMI8226 tumor cell lines, and on the human embryonic kidney (HEK293) cell line. All the compounds synthesized turned out to have better efficacy than PPA towards the tumor cell lines listed. Among them, three compounds exhibited an ability to overcome the drug resistance of tumor cells associated with the overexpression of the P-glycoprotein by modulating the work of this transporter. Luminex xMAP technology was used to assess the effect of five synthesized compounds …


Salicylic Acid And N-Hydroxypipecolic Acid At The Fulcrum Of The Plant Immunity-Growth Equilibrium, Alyssa Shields, Vanessa Shivnauth, Christian Danve M. Castroverde Mar 2022

Salicylic Acid And N-Hydroxypipecolic Acid At The Fulcrum Of The Plant Immunity-Growth Equilibrium, Alyssa Shields, Vanessa Shivnauth, Christian Danve M. Castroverde

Biology Faculty Publications

Salicylic acid (SA) and N-hydroxypipecolic acid (NHP) are two central plant immune signals involved in both resistance at local sites of pathogen infection (basal resistance) and at distal uninfected sites after primary infection (systemic acquired resistance). Major discoveries and advances have led to deeper understanding of their biosynthesis and signaling during plant defense responses. In addition to their well-defined roles in immunity, recent research is emerging on their direct mechanistic impacts on plant growth and development. In this review, we will first provide an overview of how SA and NHP regulate local and systemic immune responses in plants. We …


Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba Feb 2022

Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that synthesize aminoacyl-tRNAs to facilitate translation of the genetic code. Quality control by aaRS proofreading and other mechanisms maintains translational accuracy, which promotes cellular viability. Systematic disruption of proofreading, as recently demonstrated for alanyl-tRNA synthetase (AlaRS), leads to dysregulation of the proteome and reduced viability. Recent studies showed that environmental challenges such as exposure to reactive oxygen species can also alter aaRS synthetic and proofreading functions, prompting us to investigate if oxidation might positively or negatively affect AlaRS activity. We found that while oxidation leads to modification of several residues in Escherichia coli AlaRS, unlike …


Ultrasound 96 Probe Device Protocol For Cancer Cell Treatment, Aisling Field, Brijesh K. Tiwari, James F. Curtin, Julie R M Mondala, Janith Wanigasekara Jan 2022

Ultrasound 96 Probe Device Protocol For Cancer Cell Treatment, Aisling Field, Brijesh K. Tiwari, James F. Curtin, Julie R M Mondala, Janith Wanigasekara

Articles

Ultrasound is a sound wave with frequencies ranging between 20 kHz and 20 MHz. Ultrasound is able to temporarily and repeatedly open the BBB safely and enhance chemotherapeutic delivery without adverse effects. This novel technique in drug delivery benefits from the powerful ability of ultrasound to produce cavitation activity. Cavitation is the generation and activity of gas-filled bubbles in a medium exposed to ultrasound. As the pressure wave passes through the media, gas bubbles expand at low pressure and contract at high pressure. This leads to oscillation which produces a circulating fluid flow known as microstreaming around the bubble with …


Plasma Induced Reactive Oxygen Species-Dependent Cytotoxicity In Glioblastoma 3d Tumourspheres, Janith Wanigasekara, Carlos Barcia, Patrick J. Cullen, Brijesh Tiwari, James F. Curtin Jan 2022

Plasma Induced Reactive Oxygen Species-Dependent Cytotoxicity In Glioblastoma 3d Tumourspheres, Janith Wanigasekara, Carlos Barcia, Patrick J. Cullen, Brijesh Tiwari, James F. Curtin

Articles

The aim of this study was to determine the effects of a pin‐to‐plate cold atmospheric plasma (CAP) on U‐251 MG three‐dimensional (3D) glioblastoma spheroids under different conditions. 3D tumorspheres showed higher resistance to the CAP treatment compared to 2D monolayer cells. A single CAP treatment was able to induce cytotoxicity, while multiple CAP treatments augmented this effect. CAP was also able to induce cytotoxicity throughout the tumoursphere, and we identified that reactive oxygen species(ROS) plays a major role, while H2O2plays a partial role in CAP‐induced cytotoxicity in tumour-spheres. We conclude that ROS‐dependent cytotoxicity is induced uniformly throughout glioblastoma and epidermoid …


Physiological Roles Of Mammalian Transmembrane Adenylyl Cyclase Isoforms, Katrina F. Ostrom, Justin E. Lavigne, Tarsis F. Brust, Roland Seifert, Carmen Dessauer, Val J. Watts, Rennolds S. Ostrom Oct 2021

Physiological Roles Of Mammalian Transmembrane Adenylyl Cyclase Isoforms, Katrina F. Ostrom, Justin E. Lavigne, Tarsis F. Brust, Roland Seifert, Carmen Dessauer, Val J. Watts, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors. The transmembrane ACs display varying expression patterns across tissues, giving potential for them having a wide array of physiologic roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gαs so it was long assumed that all ACs are activated by Gαs-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form …


Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky Aug 2021

Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky

Open Educational Resources

The goal of this preparatory textbook is to give students a chance to become familiar with some terms and some basic concepts they will find later on in the Anatomy and Physiology course, especially during the first few weeks of the course.

Organization and functioning of the human organism are generally presented starting from the simplest building blocks, and then moving into levels of increasing complexity. This textbook follows the same presentation. It begins introducing the concept of homeostasis, then covers the chemical level, and later on a basic introduction to cellular level, organ level, and organ system level. This …


The Analysis Of Folate-Dependent Transcription Factor Zinc Finger Protein 410, Feifan Xu Apr 2021

The Analysis Of Folate-Dependent Transcription Factor Zinc Finger Protein 410, Feifan Xu

Senior Honors Theses

A previous study that introduced dietary folate to mice in the form of folic acid to determine if gene activity would be altered based on this biological molecule demonstrated that mice without folic acid had cognition deficits, and this phenomenon was correlated with altered gene expression in their brains. The included bioinformatic analysis revealed two main transcription factors that bind to proteins in the nucleus, and one is known as the Zinc Finger Protein 410 (Zfp410). Due to the lack of literature explaining the function of this transcription factor, this project is intended to analyze Zfp410 in detail from scratch. …


Toward The Discovery Of Biological Functions Associated With The Mechanosensor Mtl1p Of Saccharomyces Cerevisiae Via Integrative Multi-Omics Analysis, Nelson Martínez-Matías, Nataliya Chorna, Sahily González-Crespo, Lilliam Villanueva, Ingrid Montes-Rodríguez, Loyda M. Melendez-Aponte, Abiel Roche-Lima, Kelvin Carrasquillo-Carrión, Ednalise Santiago-Cartagena, Brian C. Rymond, Mohan Babu, Igor Stagljar, José R. Rodríguez-Medina Apr 2021

Toward The Discovery Of Biological Functions Associated With The Mechanosensor Mtl1p Of Saccharomyces Cerevisiae Via Integrative Multi-Omics Analysis, Nelson Martínez-Matías, Nataliya Chorna, Sahily González-Crespo, Lilliam Villanueva, Ingrid Montes-Rodríguez, Loyda M. Melendez-Aponte, Abiel Roche-Lima, Kelvin Carrasquillo-Carrión, Ednalise Santiago-Cartagena, Brian C. Rymond, Mohan Babu, Igor Stagljar, José R. Rodríguez-Medina

Biology Faculty Publications

Functional analysis of the Mtl1 protein in Saccharomyces cerevisiae has revealed that this transmembrane sensor endows yeast cells with resistance to oxidative stress through a signaling mechanism called the cell wall integrity pathway (CWI). We observed upregulation of multiple heat shock proteins (HSPs), proteins associated with the formation of stress granules, and the phosphatase subunit of trehalose 6-phosphate synthase which suggests that mtl1Δ strains undergo intrinsic activation of a non-lethal heat stress response. Furthermore, quantitative global proteomic analysis conducted on TMT-labeled proteins combined with metabolome analysis revealed that mtl1Δ strains exhibit decreased levels of metabolites of carboxylic acid metabolism, decreased …


Modeling The Bidirectional Glutamine/ Ammonium Conversion Between Cancer Cells And Cancer-Associated Fibroblasts, Peter Hinow, Gabriella Pinter, Wei Yan, Shizhen Emily Wang Jan 2021

Modeling The Bidirectional Glutamine/ Ammonium Conversion Between Cancer Cells And Cancer-Associated Fibroblasts, Peter Hinow, Gabriella Pinter, Wei Yan, Shizhen Emily Wang

Mathematical Sciences Faculty Articles

Like in an ecosystem, cancer and other cells residing in the tumor microenvironment engage in various modes of interactions to buffer the negative effects of environmental changes. One such change is the consumption of common nutrients (such as glutamine/Gln) and the consequent accumulation of toxic metabolic byproducts (such as ammonium/NH4). Ammonium is a waste product of cellular metabolism whose accumulation causes cell stress. In tumors, it is known that it can be recycled into nutrients by cancer associated fibroblasts (CAFs). Here we present monoculture and coculture growth of cancer cells and CAFs on different substrates: glutamine and ammonium. …


Single-Fluorophore Sensors For Mechanical Force In Living Cells, Sarah Kricheff Dec 2020

Single-Fluorophore Sensors For Mechanical Force In Living Cells, Sarah Kricheff

Honors Scholar Theses

Mechanotransduction is the process by which a mechanical stimulus is converted to a cellular signal. This process is heavily influential of cell morphology, differentiation, and behavior. However, altered levels of mechanical stimuli are also found in many pathological contexts. For example, cancerous cells have stiffer surrounding tissue than healthy cells, and research suggests that this alters cell behavior and promotes metastasis. Despite these findings, the cellular processes behind these signaling alterations remain widely unknown. Understanding these cascades is critical, as involved proteins can give us a deeper understanding of the role of mechanotransduction, and certain proteins can potentially be targeted …


Unconventional Constituents And Shared Molecular Architecture Of The Melanized Cell Wall Of C. Neoformans And Spore Wall Of S. Cerevisiae, Christine Chrissian, Coney Pei-Chin Lin, Emma Camacho, Arturo Casadevall, Aaron M. Neiman, Ruth E. Stark Dec 2020

Unconventional Constituents And Shared Molecular Architecture Of The Melanized Cell Wall Of C. Neoformans And Spore Wall Of S. Cerevisiae, Christine Chrissian, Coney Pei-Chin Lin, Emma Camacho, Arturo Casadevall, Aaron M. Neiman, Ruth E. Stark

Publications and Research

The fungal cell wall serves as the interface between the cell and the environment. Fungal cell walls are composed largely of polysaccharides, primarily glucans and chitin, though in many fungi stress-resistant cell types elaborate additional cell wall structures. Here, we use solid-state nuclear magnetic resonance spectroscopy to compare the architecture of cell wall fractions isolated from Saccharomyces cerevisiae spores and Cryptococcus neoformans melanized cells. The specialized cell walls of these two divergent fungi are highly similar in composition. Both use chitosan, the deacetylated derivative of chitin, as a scaffold on which a polyaromatic polymer, dityrosine and melanin, respectively, is assembled. …


The Role Of Liver Sinusoidal Endothelial Cells In Liver Malady Homeostasis, Fatima Cabral Dec 2020

The Role Of Liver Sinusoidal Endothelial Cells In Liver Malady Homeostasis, Fatima Cabral

Department of Biochemistry: Dissertations, Theses, and Student Research

Current literature described techniques for the purification of liver cell types through text alone. The techniques described for the isolation of liver sinusoidal endothelial cells as well as hepatocytes described here are modified from a published article in the Journal of Visualized experiments. The video protocol allows for the user to successfully isolate cells as the most difficult parts of the procedure are demonstrated visually. The detection of liver maladies such as the non-alcoholic fatty liver disease, the stage if this disease and differentiation between non-alcoholic and alcoholic fatty liver disease is demonstrated in the development of a unique panel …


Protonic Capacitor: Elucidating The Biological Significance Of Mitochondrial Cristae Formation, James Weifu Lee Jun 2020

Protonic Capacitor: Elucidating The Biological Significance Of Mitochondrial Cristae Formation, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

For decades, it was not entirely clear why mitochondria develop cristae? The work employing the transmembrane-electrostatic proton localization theory reported here has now provided a clear answer to this fundamental question. Surprisingly, the transmembrane-electrostatically localized proton concentration at a curved mitochondrial crista tip can be significantly higher than that at the relatively flat membrane plane regions where the proton-pumping respiratory supercomplexes are situated. The biological significance for mitochondrial cristae has now, for the first time, been elucidated at a protonic bioenergetics level: 1) The formation of cristae creates more mitochondrial inner membrane surface area and thus more protonic capacitance for …


Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta, Jordan Tillinghast Dec 2019

Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta, Jordan Tillinghast

Senior Honors Theses

This paper reviews functions of Amyloid-β (Aβ) in healthy individuals compared to the consequences of aberrant Aβ in Alzheimer’s disease (AD). As extraneuronal Aβ accumulation and plaque formation are characteristics of AD, it is reasonable to infer a pivotal role for Aβ in AD pathogenesis. Establishing progress of the disease as well as the mechanism of neurodegeneration from AD have proven difficult (Selkoe, 1994). This thesis provides evidence suggesting the pathogenesis of AD is due to dysfunctional neuronal processes involving Aβ’s synaptic malfunction, abnormal interaction with tau, and disruption of neuronal homeostasis. Significant evidence demonstrates that AD symptoms are partially …


Dual Role Of Rin1 In Cancer Cell Behavior: Is Cortactin A New Rin1-Interacting Partner?, Wei Zhang Nov 2019

Dual Role Of Rin1 In Cancer Cell Behavior: Is Cortactin A New Rin1-Interacting Partner?, Wei Zhang

FIU Electronic Theses and Dissertations

Growth factors play an essential role in abnormalities in both intracellular trafficking and signal transduction pathways responsible in normal and cancer cells. Growth factors, such as epidermal growth factor, represent a main course on the activation of mitogenic signal that contribute to the mitogen activated protein kinase (MAPK) pathway affecting cell proliferation, which is driven by Ras GTPases. However, it also induces a profound morphological change by reorganization actin and other cytoskeleton proteins, which are driven by other GTPases (i.e., Rho and Rac). Ras interference 1 (Rin1) is a key cytosolic protein, that regulates both membrane trafficking and signaling pathways …


The Role Of Inositol Polyphosphate-4-Phosphatase Type Ii B (Inpp4b) In Obese Models And Endocrine Cancers, Manqi Zhang Nov 2019

The Role Of Inositol Polyphosphate-4-Phosphatase Type Ii B (Inpp4b) In Obese Models And Endocrine Cancers, Manqi Zhang

FIU Electronic Theses and Dissertations

INPP4B is a dual-specificity phosphatase and a tumor suppressor in prostate and breast cancers. Progression of the prostate and breast cancers depends on the androgen receptor (AR) or estrogen receptor alpha (ERα) signaling, respectively. In this work we demonstrated that INPP4B reprograms ERα transcriptional activity in breast cancer. INPP4B maintains expression and protein levels of progesterone receptor (PR), an ERα direct target gene required for mammary gland development. Consistently we demonstrated that Inpp4b knockout severely impairs lateral branching in the mammary gland of maturing virgin females. In advanced prostate cancer, activation and transcriptional reprogramming of AR frequently coincides with the …


Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan Mar 2019

Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

One of the major goals in large-scale genomic studies is to identify genes with a prognostic impact on time-to-event outcomes which provide insight into the disease's process. With rapid developments in high-throughput genomic technologies in the past two decades, the scientific community is able to monitor the expression levels of tens of thousands of genes and proteins resulting in enormous data sets where the number of genomic features is far greater than the number of subjects. Methods based on univariate Cox regression are often used to select genomic features related to survival outcome; however, the Cox model assumes proportional hazards …


Composition Of The Survival Motor Neuron (Smn) Complex In Drosophila Melanogaster, A. Gregory Matera, Amanda C. Raimer, Casey A. Schmidt, Jo A. Kelly, Gaith N. Droby, David Baillat, Sara Ten Have, Angus I. Lamond, Eric J. Wagner, Kelsey M. Gray Feb 2019

Composition Of The Survival Motor Neuron (Smn) Complex In Drosophila Melanogaster, A. Gregory Matera, Amanda C. Raimer, Casey A. Schmidt, Jo A. Kelly, Gaith N. Droby, David Baillat, Sara Ten Have, Angus I. Lamond, Eric J. Wagner, Kelsey M. Gray

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Spinal Muscular Atrophy (SMA) is caused by homozygous mutations in the human survival motor neuron 1 (SMN1) gene. SMN protein has a well-characterized role in the biogenesis of small nuclear ribonucleoproteins (snRNPs), core components of the spliceosome. SMN is part of an oligomeric complex with core binding partners, collectively called Gemins. Biochemical and cell biological studies demonstrate that certain Gemins are required for proper snRNP assembly and transport. However, the precise functions of most Gemins are unknown. To gain a deeper understanding of the SMN complex in the context of metazoan evolution, we investigated its composition in Drosophila …


Interaction And Regulation Between Lipid Mediator Phosphatidic Acid And Circadian Clock Regulators, Sang-Chul Kim, Sang-Chul Kim, Dmitri Nusinow, Maria Sorkin, Maria Sorkin, Jose Pruneda-Paz, Xuemin Wang, Xuemin Wang Feb 2019

Interaction And Regulation Between Lipid Mediator Phosphatidic Acid And Circadian Clock Regulators, Sang-Chul Kim, Sang-Chul Kim, Dmitri Nusinow, Maria Sorkin, Maria Sorkin, Jose Pruneda-Paz, Xuemin Wang, Xuemin Wang

Biology Department Faculty Works

Circadian clocks play important roles in regulating cellular metabolism, but the reciprocal effect that metabolism has on the clock is largely unknown in plants. Here we show that the central glycerolipid metabolite and lipid mediator phosphatidic acid (PA) interacts with and modulates the function of the core clock regulators LATE ELONGATED HYPOCOTYL (LHY) and CIRCADIAN CLOCK ASSOCIATED1 (CCA1) in Arabidopsis thaliana. PA reduced the ability of LHY and CCA1 to bind the promoter of their target gene TIMING OF CAB EXPRESSION1. Increased PA accumulation and inhibition of PA-producing enzymes had opposite effects on circadian clock outputs. Diurnal change in levels …


Deletion Of Mgr2p Affects The Gating Behavior Of The Tim23 Complex, Oygul Mirzalieva, Shinhye Jeon, Kevin Damri, Ruth Hartke, Layla Drwesh, Keren Demishtein-Zohary, Abdussalam Azem, Cory D. Dunn, Pablo M. Peixoto Jan 2019

Deletion Of Mgr2p Affects The Gating Behavior Of The Tim23 Complex, Oygul Mirzalieva, Shinhye Jeon, Kevin Damri, Ruth Hartke, Layla Drwesh, Keren Demishtein-Zohary, Abdussalam Azem, Cory D. Dunn, Pablo M. Peixoto

Publications and Research

The TIM23 complex is a hub for translocation of preproteins into or across the mitochondrial inner membrane. This dual sorting mechanism is currently being investigated, and in yeast appears to be regulated by a recently discovered subunit, the Mgr2 protein. Deletion of Mgr2p has been found to delay protein translocation into the matrix and accumulation in the inner membrane. This result and other findings suggested that Mgr2p controls the lateral release of inner membrane proteins harboring a stop-transfer signal that follows an N-terminal amino acid signal. However, the mechanism of lateral release is unknown. Here, we used patch clamp electrophysiology …


Data On Spectrum-Based Fluorescence Resonance Energy Transfer Measurement Of E. Coli Multidrug Transporter Acrb, Yuguang Cai, Thomas E. Wilkop, Yinan Wei Dec 2018

Data On Spectrum-Based Fluorescence Resonance Energy Transfer Measurement Of E. Coli Multidrug Transporter Acrb, Yuguang Cai, Thomas E. Wilkop, Yinan Wei

Chemistry Faculty Publications

This paper presented the dataset of correction parameters used in the determination of the energy transfer efficiencies from the spectrum-based fluorescence resonance energy transfer (FRET) measurement in a trimeric membrane protein AcrB. The cyan fluorescent protein (CFP) and yellow fluorescent protein (YPet) were used as the donor and acceptor, respectively. Two AcrB fusion proteins were constructed, AcrB-CFP and AcrB-YPet. The proteins were co-expressed in Escherichia coli cells, and energy transfer efficiency were determined in live cells. To obtain reliable energy transfer data, a complete set of correction parameters need to be first determined to accommodate for factors such as background …


Superoxide Dismutase C Modulates Macropinocytosis And Phagocytosis In Dictyostelium Discoideum, Cong Gu Nov 2018

Superoxide Dismutase C Modulates Macropinocytosis And Phagocytosis In Dictyostelium Discoideum, Cong Gu

FIU Electronic Theses and Dissertations

Macropinocytosis and phagocytosis, two actin-dependent and clathrin independent events of endocytosis, enable the cells such as macrophages and neutrophils to either internalize pathogens and initiates the human innate immune response or serve as a direct entry route for productive infection of pathogen. Dictyostelium discoideum, soil-living amoeba, a unicellular eukaryote that could professionally internalize fluid phase or particles several folds more than that of macrophages and neutrophils. Additionally, multiple key signaling pathways are conserved between Dictyostelium and mammalian cells, including pathways affecting small GTPases Ras and Rac and their downstream effectors, and F-Actin remodeling. All these traits makes Dictyostelium an …


Pias-Family Proteins Negatively Regulate Glis3 Transactivation Function Through Sumo Modification In Pancreatic Β Cells, Tyler M. Hoard, Xiaoping Yang, Anton M. Jetten, Gary T. Zeruth Dr. Jul 2018

Pias-Family Proteins Negatively Regulate Glis3 Transactivation Function Through Sumo Modification In Pancreatic Β Cells, Tyler M. Hoard, Xiaoping Yang, Anton M. Jetten, Gary T. Zeruth Dr.

Faculty & Staff Research and Creative Activity

Gli-similar 3 (Glis3) is Krüppel-like transcription factor associated with the transcriptional regulation of insulin. Mutations within the Glis3 locus have been implicated in a number of pathologies including diabetes mellitus and hypothyroidism. Despite its clinical significance, little is known about the proteins and posttranslational modifications that regulate Glis3 transcriptional activity. In this report, we demonstrate that the SUMO-pathway associated proteins, PIASy and Ubc9 are capable of regulating Glis3 transactivation function through a SUMO-dependent mechanism. We present evidence that SUMOylation of Glis3 by PIAS-family proteins occurs at two conserved lysine residues within the Glis3 N-terminus and modification of Glis3 by SUMO …


Impact Of San-Mediated Signaling On Glioblastoma And Neuroblastoma Metabolism, Monica Rodriguez Silva Jun 2018

Impact Of San-Mediated Signaling On Glioblastoma And Neuroblastoma Metabolism, Monica Rodriguez Silva

FIU Electronic Theses and Dissertations

Glioblastoma (GBM) is the most common and aggressive type of brain cancer, with an average life expectancy of 15 months. The standard of care for GBM, surgery accompanied by radiation and chemotherapy (temozolomide-TMZ), has not changed in over 10 years illustrating the need for new and efficacious treatments. Therefore, it is imperative to improve our knowledge of GBM physiology to understand the mechanisms driving recurrence and chemoresistance so that more effective therapeutic options can be developed. Mitochondria-cell communication is key to monitor and maintain both mitochondrial and cellular health, and signaling events on the outer mitochondrial membrane (OMM) have emerged …


Aβ42 Protofibrils Interact With, And Are Trafficked Through, Microglial-Derived Microvesicles, Lisa Gouwens, Mudar Ismail, Victoria Rogers, Nathan Zeller, Evan Garrad, Fatima Amtashar, Nyasha Makoni, David Osborn, Michael Nichols Jun 2018

Aβ42 Protofibrils Interact With, And Are Trafficked Through, Microglial-Derived Microvesicles, Lisa Gouwens, Mudar Ismail, Victoria Rogers, Nathan Zeller, Evan Garrad, Fatima Amtashar, Nyasha Makoni, David Osborn, Michael Nichols

Chemistry & Biochemistry Faculty Works

Microvesicles (MVs) and exosomes comprise a class of cell-secreted particles termed extracellular vesicles (EVs). These cargo-holding vesicles mediate cell-to-cell communication and have recently been implicated in neurodegenerative diseases such as Alzheimer’s disease (AD). The two types of EVs are distinguished by the mechanism of cell release and their size, with the smaller exosomes and the larger MVs ranging from 30 to 100 nm and 100 nm to 1 μm in diameter, respectively. MV numbers are increased in AD and appear to interact with amyloid-β peptide (Aβ), the primary protein component of the neuritic plaques in the AD brain. Because microglial …