Physiology Commons^™

An Archaeal Trna-Synthetase Complex That Enhances Aminoacylation Under Extreme Conditions, Vlatka Godinic-Mikulcic, Jelena Jaric, Corinne D. Hausmann, Michael Ibba, Ivana Weygand-Durasevic

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) play an integral role in protein synthesis, functioning to attach the correct amino acid with its cognate tRNA molecule. AaRSs are known to associate into higher-order multi-aminoacyl-tRNA synthetase complexes (MSC) involved in archaeal and eukaryotic translation, although the precise biological role remains largely unknown. To gain further insights into archaeal MSCs, possible protein-protein interactions with the atypical Methanothermobacter thermautotrophicus seryl-tRNA synthetase (MtSerRS) were investigated. Yeast two-hybrid analysis revealed arginyl-tRNA synthetase (MtArgRS) as an interacting partner of MtSerRS. Surface plasmon resonance confirmed stable complex formation, with a dissociation constant (KD) of 250 nm. Formation of the MtSerRS·MtArgRS complex …

Association Between Chronic Liver And Colon Inflammation During The Development Of Murine Syngeneic Graft-Versus-Host Disease, Jason Anthony Brandon, Jacqueline Perez-Rodriguez, C. Darrell Jennings, Donald A. Cohen, Vishal J. Sindhava, Subbarao Bondada, Alan M. Kaplan, J. Scott Bryson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The murine model of cyclosporine A (CsA)-induced syngeneic graft-versus-host disease (SGVHD) is a bone marrow (BM) transplantation model that develops chronic colon inflammation identical to other murine models of CD4⁺ T cell-mediated colitis. Interestingly, SGVHD animals develop chronic liver lesions that are similar to the early peribiliary inflammatory stages of clinical chronic liver disease, which is frequently associated with inflammatory bowel disease (IBD). Therefore, studies were initiated to investigate the chronic liver inflammation that develops in the SGVHD model. To induce SGVHD, mice were lethally irradiated, reconstituted with syngeneic BM, and treated with CsA. All of the SGVHD animals …

Poxa, Yjek And Elongation Factor P Coordinately Modulate Virulence And Drug Resistance In Salmonella Enterica, William Wiley Navarre, Shicong Zou, Hervé Roy, Jinglin Lucy Xie, Alexei Savchenko, Alexander Singer, Elena Edvokimova, Lynne R. Prost, Runjun Kumar, Michael Ibba, Ferric C. Fang

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We report an interaction between poxA, encoding a paralog of lysyl tRNA-synthetase, and the closely linked yjeK gene, encoding a putative 2,3-β-lysine aminomutase, that is critical for virulence and stress resistance in Salmonella enterica. Salmonella poxA and yjeK mutants share extensive phenotypic pleiotropy, including attenuated virulence in mice, an increased ability to respire under nutrient-limiting conditions, hypersusceptibility to a variety of diverse growth inhibitors, and altered expression of multiple proteins, including several encoded on the SPI-1 pathogenicity island. PoxA mediates posttranslational modification of bacterial elongation factor P (EF-P), analogous to the modification of the eukaryotic EF-P homolog, eIF5A, with …

Redox Status Affects The Catalytic Activity Of Glutamyl-Trna Synthetase, Assaf Katz, Ranat Banerjee, Merly De Armas, Michael Ibba, Omar Orellana

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Glutamyl-tRNA synthetases (GluRS) provide Glu-tRNA for different processes including protein synthesis, glutamine transamidation and tetrapyrrole biosynthesis. Many organisms contain multiple GluRSs, but whether these duplications solely broaden tRNA specificity or also play additional roles in tetrapyrrole biosynthesis is not known. Previous studies have shown that GluRS1, one of two GluRSs from the extremophile Acidithiobacillus ferrooxidans, is inactivated when intracellular heme is elevated suggesting a specific role for GluRS1 in the regulation of tetrapyrrole biosynthesis. We now show that, in vitro, GluRS1 activity is reversibly inactivated upon oxidation by hemin and hydrogen peroxide. The targets for oxidation-based inhibition were …

Protein Evolution Via Amino Acid And Codon Elimination, Lise Goltermann, Marie Sofie Yoo Larsen, Ranat Banerjee, Andreas C. Joerger, Michael Ibba, Thomas Bentin

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background
Global residue-specific amino acid mutagenesis can provide important biological insight and generate proteins with altered properties, but at the risk of protein misfolding. Further, targeted libraries are usually restricted to a handful of amino acids because there is an exponential correlation between the number of residues randomized and the size of the resulting ensemble. Using GFP as the model protein, we present a strategy, termed protein evolution via amino acid and codon elimination, through which simplified, native-like polypeptides encoded by a reduced genetic code were obtained via screening of reduced-size ensembles.

Methodology/Principal Findings
The strategy involves combining a sequential …

How The Sequence Of A Gene Can Tune Its Translation, Kurt Fredrick, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Sixty-one codons specify 20 amino acids, offering cells many options for encoding a polypeptide sequence. Two new studies (Cannarrozzi et al., 2010, Tuller et al., 2010) now foster the idea that patterns of codon usage can control ribosome speed, fine-tuning translation to increase the efficiency of protein synthesis.

The Correlation Between Visual Observations And Inclinometric Measurements For Special Tests Related To Patellofemoral Pain Syndrome, Erin Quada

Human Movement Studies & Special Education Theses & Dissertations

Patellofemoral pain syndrome (PFPS) is generally described as an insidious onset with pain increasing during running, jumping, ascending and descending stairs as well as sitting with the knees flexed for an extended period of time. Clinicians often use special tests in injury evaluations and range of motion assessments, usually making a visual observation of that status of the patient. The purpose of this study was to examine how interval measurements utilized in flexibility and range of motion assessments correlate with visual observations of special tests (active knee extension test, Thomas test, Ober's test, rectus femoris flexibility, and Craig's test). The …

The Effects Of Cocaine And Ecstasy On Cardiac Myocytes And The Intact Myocardium, David A. Tiangco

Theses and Dissertations in Biomedical Sciences

Cocaine and ecstasy are widely used illicit drugs. Both drugs have undergone intense scrutiny as information regarding their side-effects has become available. One important yet incomplete area of investigation pertains to their effects on the heart. The purpose of the current studies was to test the hypothesis that exposure to cocaine or ecstasy will adversely affect cellular homeostasis and normal heart function. Cultured cardiac myocytes (H9c2) and New Zealand White rabbits (Oryctolagus cuniculus) were used to measure the responses to various concentrations of cocaine or ecstasy at both the cellular and intact organ system levels. We observed that cocaine and …

Charge Switch Nucleotides, John G. K. Williams, Gregory R. Bashford, Jiyan Chen, Dan Draney, Nara Narayanan, Bambi L. Reynolds, Pamela Sheaff

Biomedical Imaging and Biosignal Analysis Laboratory

The present invention provides compounds, methods and systems for sequencing nucleic acid using single molecule detection. Using labeled NPs that exhibit charge-switching behavior, single-molecule DNA sequencing in a microchannel sorting system is realized. In operation, sequencing products are detected enabling real-time sequencing as successive detectable moieties flow through a detection channel. By electrically sorting charged molecules, the cleaved product molecules are detected in isolation Without interference from unincorporated NPs and Without illuminating the polymerase-DNA complex.

Mechanism Of Catch Force: Tethering Of Thick And Thin Filaments By Twitchin., Thomas M Butler, Marion J Siegman

Department of Molecular Physiology and Biophysics Faculty Papers

Catch is a mechanical state occurring in some invertebrate smooth muscles characterized by high force maintenance and resistance to stretch during extremely slow relaxation. During catch, intracellular calcium is near basal concentration and myosin crossbridge cyctng rate is extremely slow. Catch force is relaxed by a protein kinase A-mediated phosphorylation of sites near the N- and C- temini of the minititin twitchin (approximately 526 kDa). Some catch force maintenance car also occur together with cycling myosin crossbridges at submaximal calcium concentrations, but not when the muscle is maximally activated. Additionally, the link responsible for catch can adjust during shortening of …

The Female Athlete, Dilip R. Patel, Donald E. Greydanus, Hatim A. Omar

Pediatrics Faculty Publications

The female athlete has today became an accepted part of sports in elementary school, junior high, senior high, and college. This chapter covers various aspects of the prepubertal and pubertal female athlete. An historical perspective will be presented and selected comments provided on psychological and physiologic aspects of the female athlete. Concepts of adolescent gynecology are reviewed, including breast concerns and menstrual dilemmas in relation to sports activity. Exercise during pregnancy is also considered. Iron deficiency anemia and stress urinary incontinence

Effect Of Exogenous Leptin On Thrombotic And Metabolic Profiles Of Fvb/B6 Lipodystrophic Mice, Hoda Chaouki Kadouh

Wayne State University Theses

Lipodystrophy caused by fat deficiency contributes to metabolic disease for which several treatment modalities have been implemented, with leptin therapy being the most effective to date. In addition to playing a role in energy homeostasis and metabolism, leptin was also shown to play a pro-thrombotic role in mice. This role was not examined in fatless mice, neither was thrombosis measured. The AZIP/F-1 (FVB) lipodystrophic mouse appeared to have a prolonged arterial occlusion time (p〈0.05) in a trial done in our lab, with clotting factors being normal. The present study was designed to observe the thrombotic and metabolic characteristics of fatless …

A Specific Regulatory Role For Sgtα On The Maturation And Activation Of Steroid Hormone Receptors, Atanu Paul

Open Access Theses & Dissertations

Steroid hormone receptors (SHRs) are ligand-dependent transcription factors belonging to the nuclear receptor superfamily. These receptors regulate various physiological functions in higher ordered eukaryotes. In the absence of hormone these receptors form a complex with molecular chaperones such as Hsp90 and Hsp70 and other cochaperones in the cytoplasm. Association with the Hsp90-Hsp70 chaperone machinery leads to the maturation of the Ligand Binding Domain (LBD) of the receptors and enables the receptors to bind hormone with high affinity. Upon binding with a specific hormone the receptors are translocated into the nucleus where they initiate transcription of specific genes. Although the involvement …

Relationships Between Jump Characteristics Of Collegiate Female Athletes Competing In Different Disciplines, Christopher J. Macdonalds, Hugh S. Lamont, John C. Garner, Jeremy A. Gentles, Ashley A. Kavanaugh, Michael H. Stone

ETSU Faculty Works

No abstract provided.

Balance Training Reduces Falls Risk In Older Individuals With Type 2 Diabetes, Steven Morrison, Sheri R. Colberg, Mita Mariano, Henri K. Parson, Arthur I. Vinik

Rehabilitation Sciences Faculty Publications

OBJECTIVE - This study assessed the effects of balance/strength training on falls risk and posture in older individuals with type 2 diabetes.

RESEARCH DESIGN AND METHODS - Sixteen individuals with type 2 diabetes and 21 age-matched control subjects (aged 50-75 years) participated. Postural stability and falls risk was assessed before and after a 6-week exercise program.

RESULTS - Diabetic individuals had significantly higher falls risk score compared with control subjects. The diabetic group also exhibited evidence of mild-to-moderate neuropathy, slower reaction times, and increased postural sway. Following exercise, the diabetic group showed significant improvements in leg strength, faster reaction times, …

Breast Disorders In Children And Adolescents, Donald E. Greydanus, Hatim A. Omar, Lyubov A. Matytsina, Artemis Tsitsika

Pediatrics Faculty Publications

Concerns about problems of the breast are often noted in adolescents and their parents. This review discusses issues and disorders of the breast in children and adolescents, starting with basic principles of embryology and adolescent breast development. Concepts that are covered include congenital breast disorders, abnormal timing of breast development, breast asymmetry, underdeveloped breasts, breast atrophy, tuberous breasts, mammary hyperplasia, fibroadenoma, giant fibroadenoma, cystosarcoma phyllodes, intraductal breast papilloma, adenocarcinoma, mastitis, traumatic breast disorders, benign breast disease, fibrocystic change, mastalgia, gynocomastia, and galactorrhea. A number of figures are provided illustrating breast pathology. Clinicians caring for children and adolescents are encouraged to …

Menstrual Disorders In Adolescent Females, Donald E. Greydanus, Hatim A. Omar, Artemis Tsitsika, Dilip R. Patel

Pediatrics Faculty Publications

Onset of menstruation (i.e., menarche) is a determining event of the adolescent female signifying the progress of puberty, which in the majotity of cases is visibly initiated with thelarche (onset of breast development or breast buds). Menarche usually occurs during the earlier time of the second decade of life and ends with menopause, typically in the 5th decade of life. The adolescent can present with a wide variety of menstrual dilemmas and disorders which will be discussed in this chapter.

Charge Switch Nucleotides, John G. K. Williams, Gregory R. Bashford, Jiyan Chen, Dan Draney, Nara Narayanan, Bambi Reynolds, Pamela Sheaff

Biomedical Imaging and Biosignal Analysis Laboratory

The present invention provides compounds, methods and systems for sequencing nucleic acid using single molecule detection. Using labeled NPs that exhibit charged-switching behavior, single-molecule DNA sequencing in a microchannel sorting system is realized. In operation, sequencing products are detected enabling real-time sequencing as successive detectable moieties flow through a detection channel. By electrically sorting charged molecules, the cleaved product molecules are detected in isolation Without interference from unincorporated NPs and Without illuminating the polymerase-DNA complex.

Computational Prediction Of The Agregated Structure Of Denatured Lysozyme, Pongsathorn Chotikasemsri

Masters Theses & Specialist Projects

Mis-folded proteins and their associated aggregates are a contributing factor in some human diseases. In this study we used the protein lysozyme as a model to define aggregation structures under denaturing conditions. Sasahara et al. (2007), Frare et al. (2009, 2006), and Rubin et al. (2008) observed conditions where heat denatured lysozyme formed fibril structures that were observed to be 8-17 nanometers in diameter under the electron microscope. Even though the crystal structure of lysozyme is known, the denatured form of this protein is still unknown. Therefore, we used Rosetta++ protein folding and blind docking software to create in silico …

The Acute Effects Of Whole Body Vibration On Isometric Mid-Thigh Pull Performance, W. Guy Hornsby, Mark A. South, Ashley Kavanaugh, Andrew S. Layne, G. Gregory Haff, William A. Sands, Marco Cardinale, Michael W. Ramsey, Michael H. Stone

ETSU Faculty Works

Acute exposure to vibration has been suggested to produce transient increases in muscular strength (1,2,8), vertical jump displacement (4,8), and power output (2,6,7) recorded while performing various tasks. It has been hypothesized that the reported acute vibration induced increases in performance occur as a result of alterations in neuromuscular stimulation (1,3,4). Specifically, most studies have ascribed the observed improvements to the likeliness of Whole Body Vibration (WBV) in producing a “tonic vibration reflex” (TVR) in which the primary nerve endings of the Ia afferents of the muscle spindle are activated. This is thought to result in the excitation of the …

Trnas: Cellular Barcodes For Amino Acids, Ranat Banerjee, Shawn Chen, Kiley Dare, Marla Gilreath, Mette Praetorius-Ibba, Medha Raina, Noah M. Reynolds, Theresa E. Rogers, Hervé Roy, Srujana S. Yadavalli, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The role of tRNA in translating the genetic code has received considerable attention over the last 50 years, and we now know in great detail how particular amino acids are specifically selected and brought to the ribosome in response to the corresponding mRNA codon. Over the same period, it has also become increasingly clear that the ribosome is not the only destination to which tRNAs deliver amino acids, with processes ranging from lipid modification to antibiotic biosynthesis all using aminoacyl‐tRNAs as substrates. Here we review examples of alternative functions for tRNA beyond translation, which together suggest that the role of …

Motivational Profiles And Their Associations With Achievement Outcomes, Bo Shen, Nate Mccaughtry, Jeffrey J. Martin, Mariane Fahlman

Kinesiology, Health and Sport Studies

With the belief that theoretical integration in motivation may help us better understand motivational behavior, we designed this study to explore adolescents’ motivational profiles and their associations with knowledge acquisition, leisure-time exercise behaviors, and cardiorespiratory fitness. Middle school students from a large urban inner-city school district (N = 603, ages 12–14) completed questionnaires assessing motivational constructs and leisure-time exercise behavior. Knowledge and cardiorespiratory fitness were also assessed with a knowledge test and the Progressive Aerobic Cardiovascular Endurance Run (PACER) test, respectively. Using hierarchical cluster analysis, we found that students’ motivation in physical education could be explained from a multi-theoretical …

Prediction Of Birth Weight By Cotinine Levels During Pregnancy In A Population Of African American Smokers, Ayman A.E. El-Mohandes, Michele Kiely, Marie G. Gantz, Susan M. Blake, M Nabil El-Khorazaty

Publications and Research

Objective—The goal was to investigate the association between maternal salivary cotinine levels (SCLs) and pregnancy outcome among African Americans smokers

Methods—In a randomized controlled trial conducted in 2001-2004 in Washington, D.C. 714 women (126 active smokers (18%)) were tested for SCLs at the time of recruitment and later in pregnancy. Sociodemographic health risks and pregnancy outcomes were recorded.

Results—Birth weights were significantly lower for infants born to mothers with baseline SCLs of ≥20 ng/ml compared to/ml (p=0.024), ≥50 ng/ml compared to/ml (p=0.002), ≥100 ng/ml compared to/ml (p=0.002), in bivariate analyses. In linear regression analyses adjusting for sociodemographic …

Broad Range Amino Acid Specificity Of Rna-Dependent Lipid Remodelling By Multiple Peptide Resistance Factors, Hervé Roy, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacylphosphatidylglycerol synthases (aaPGSs) are multiple peptide resistance factors that transfer amino acids from aminoacyl-tRNAs to phosphatidylglycerol (PG) in the cytoplasmic membrane. Aminoacylation of PG is used by bacteria to decrease the net negative charge of the cell envelope, diminishing affinity for charged molecules and allowing for adaptation to environmental changes. Lys-PGS, which transfers lysine to PG, is essential for the virulence of certain pathogens, providing resistance to both host cationic antimicrobial peptides and therapeutic antibiotics. Ala-PGS was also recently described, but little is known about the possible activities of other members of the highly diverse aaPGS family of proteins. Systematic …

The Cca Anticodon Specifies Separate Functions Inside And Outside Translation In Bacillus Cereus, Sandro F. Ataide, Theresa E. Rogers, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacillus cereus 14579 encodes two tRNAs with the CCA anticodon, tRNA^Trp and tRNA^Other. tRNA^Trp was separately aminoacylated by two enzymes, TrpRS1 and TrpRS2, which share only 34% similarity and display different catalytic capacities and specificities. TrpRS1 was 18-fold more proficient at aminoacylating tRNA^Trp with Trp, while TrpRS2 more efficiently utilizes the Trp analog 5-hydroxy Trp. tRNA^Other was not aminoacylated by either TrpRS but instead by the combined activity of LysRS1 and LysRS2, which recognized sequence elements absent from tRNA^Trp. Polysomes were found to contain tRNA^Trp, consistent with its role in …

The Effects Of Repeated Anaerobic Bouts On Immune Parameters, James C. Sivley

Masters Theses & Specialist Projects

To date, the exercise-induced immune response in has only been evaluated in subjects performing aerobic exercise. The primary purpose of this study is to determine if repeated bouts of anaerobic exercise will induce a similar immune response in human subjects as exhibited by aerobic exercise. Secondary to immune function, an analysis of performance from trial to trial will be made. Nine males between the ages of 18-25 were selected on a volunteer basis to participate in this study. Subjects performed Wingate tests set in 3 series with 120 seconds between trials within series and 405 seconds between series for an …

Trunk Rotation Movement In Tennis Backhand, Hsin-Chen Fanchiang

All-Inclusive List of Electronic Theses and Dissertations

This study analyzed the effects of gender, strike technique, power level, and trial factors on tennis athletes performing backhand strokes with the incoming ball launched by a serving-stand. Five male and five female college tennis athletes volunteered as subjects. Each subject had 25 data points including joint centers of right and left sides for the 5th metatarsal, lateral malleolus, knees, hips, shoulders, elbows, wrists and MP joints, chin, forehead, seven points on the racket (handle, head, neck, upper right and left rims, and lower right and left rims), and the ball were recorded by two video cameras (60Hz). Each of …

Effects Of Estrogen On Muscle Damage In Response To An Acute Resistance Exercise Protocol, Megan R. Wolf

Honors Scholar Theses

Creatine Kinase (CK) is used as a measure of exercise-induced muscle membrane damage. During acute eccentric (muscle lengthening) exercise, muscle sarcolemma, sarcoplasmic reticulum, and Z-lines are damaged, thus causing muscle proteins and enzymes to leak into the interstitial fluid.

Strenuous eccentric exercise produces an elevation of oxygen free radicals, which further increases muscle damage. Muscle soreness and fatigue can be attributed to this membrane damage. Estradiol, however, may preserve membrane stability post-exercise (Brancaccio, Maffulli, & Limongelli, 2007; Carter, Dobridge, & Hackney, 2001; Tiidus, 2001). Because estradiol has a similar structure to Vitamin E, which is known to have antioxidant properties, …

Mechanisms Of Regulation Of Proximal Tubule Sodium Transporters In Obesity-Induced Hypertension, Marta A. Ambrozewicz

Theses and Dissertations in Biomedical Sciences

Hypertension is one of the common complications of obesity. Using a rat model of diet induced obesity and hypertension we investigated some of the mechanisms that are involved in regulation of blood pressure in obesity. The first aim of this study was to determine the role of proximal tubule transporters on the renal sodium handling in obese hypertensive (OP) and lean normotensive (OR) rats. An acute increase in renal perfusion pressure resulted in a blunted natriuretic response in OP vs. OR rats and indicated that increased sodium reabsorption in the proximal tubule is casual, at least in part, for hypertension …

Resampling And Editing Of Mischarged Trna Prior To Translation Elongation, Jiqiang Ling, Byung Ran So, Srujana S. Yadavalli, Hervé Roy, Shinichiro Shoji, Kurt Fredrick, Karin Musier-Forsyth, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Faithful translation of the genetic code depends on the GTPase EF-Tu delivering correctly charged aminoacyl-tRNAs to the ribosome for pairing with cognate codons. The accurate coupling of cognate amino acids and tRNAs by the aminoacyl-tRNA synthetases is achieved through a combination of substrate specificity and product editing. Once released by aminoacyl-tRNA synthetases, both cognate and near-cognate aminoacyl-tRNAs were considered to be committed to ribosomal protein synthesis through their association with EF-Tu. Here we show instead that aminoacyl-tRNAs in ternary complex with EF-Tu•GTP can readily dissociate and rebind to aminoacyl-tRNA synthetases. For mischarged species, this allows resampling by the product editing …