Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Physiology

2010

Institution
Keyword
Publication
Publication Type
File Type

Articles 1 - 21 of 21

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Lateral Blood Flow Velocity Estimation Based On Ultrasound Speckle Size Change With Scan Velocity, Tiantian Xu, Gregory R. Bashford Dec 2010

Lateral Blood Flow Velocity Estimation Based On Ultrasound Speckle Size Change With Scan Velocity, Tiantian Xu, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Conventional (Doppler-based) blood flow velocity measurement methods using ultrasound are capable of resolving the axial component (i.e., that aligned with the ultrasound propagation direction) of the blood flow velocity vector. However, these methods are incapable of detecting blood flow in the direction normal to the ultrasound beam. In addition, these methods require repeated pulse-echo interrogation at the same spatial location. A new method has been introduced which estimates the lateral component of blood flow within a single image frame using the observation that the speckle pattern corresponding to blood reflectors (typically red blood cells) stretches (i.e., is smeared ...


Elucidating Functional Roles For Myogenin In Adult Skeletal Muscle Metabolism, Exercise Capacity, And Regeneration, Jesse Flynn Dec 2010

Elucidating Functional Roles For Myogenin In Adult Skeletal Muscle Metabolism, Exercise Capacity, And Regeneration, Jesse Flynn

UT GSBS Dissertations and Theses (Open Access)

The four basic helix-loop-helix myogenic transcription factors, myogenin, Myf5, MRF4, and MyoD are critical for embryonic skeletal muscle development. Myogenin is necessary for the terminal differentiation of myoblasts into myofibers during embryogenesis, but little is known about the roles played by myogenin in adult skeletal muscle function and metabolism. Furthermore, while metabolism is a well-studied physiological process, how it is regulated at the transcriptional level remains poorly understood. In this study, my aim was to determine the function of myogenin in adult skeletal muscle metabolism, exercise capacity, and regeneration. To investigate this, I utilized a mouse strain harboring the Myogflox ...


Relationship Of Flight And Reproduction In Beet Armyworm, Spodoptera Exigua (Lepidoptera: Noctuidae), A Migrant Lacking The Oogenesis-Flight Syndrome, Xing Fu Jiang, Li Zhi Luo, Thomas W. Sappington Nov 2010

Relationship Of Flight And Reproduction In Beet Armyworm, Spodoptera Exigua (Lepidoptera: Noctuidae), A Migrant Lacking The Oogenesis-Flight Syndrome, Xing Fu Jiang, Li Zhi Luo, Thomas W. Sappington

Entomology Publications

The beet armyworm, Spodoptera exigua, undertakes long-distance migration. We used flight mills to investigate the interaction between flight and reproduction in this species given the apparent absence of the oogenesis-flight syndrome. This syndrome, common in many migratory insects, is characterized by a suite of traits including migration during the pre-oviposition period followed by a switch to oogenesis. No negative effects of inter-ovipositional flight on lifetime fecundity were observed. Instead, adult reproductive output suffered when female flight was initiated the first day after eclosion and before oviposition, suggesting that migratory flight overlaps with the oviposition period rather than being confined to ...


Hippocampal C-Jun-N-Terminal Kinases Serve As Negative Regulators Of Associative Learning, Tessi Sherrin, Thomas Blank, Cathrin Hippel, Martin Rayner, Roger J. Davis, Cedomir Todorovic Oct 2010

Hippocampal C-Jun-N-Terminal Kinases Serve As Negative Regulators Of Associative Learning, Tessi Sherrin, Thomas Blank, Cathrin Hippel, Martin Rayner, Roger J. Davis, Cedomir Todorovic

Davis Lab Publications

In the adult mouse, signaling through c-Jun N-terminal kinases (JNKs) links exposure to acute stress to various physiological responses. Inflammatory cytokines, brain injury and ischemic insult, or exposure to psychological acute stressors induce activation of hippocampal JNKs. Here we report that exposure to acute stress caused activation of JNKs in the hippocampal CA1 and CA3 subfields, and impaired contextual fear conditioning. Conversely, intrahippocampal injection of JNKs inhibitors sp600125 (30 mum) or D-JNKI1 (8 mum) reduced activity of hippocampal JNKs and rescued stress-induced deficits in contextual fear. In addition, intrahippocampal administration of anisomycin (100 mug/mul), a potent JNKs activator, mimicked ...


Requirement Of Jip1-Mediated C-Jun N-Terminal Kinase Activation For Obesity-Induced Insulin Resistance, Caroline Morel, Claire L. Standen, Dae Young Jung, Susan Gray, Helena Ong, Richard A. Flavell, Jason K. Kim, Roger J. Davis Oct 2010

Requirement Of Jip1-Mediated C-Jun N-Terminal Kinase Activation For Obesity-Induced Insulin Resistance, Caroline Morel, Claire L. Standen, Dae Young Jung, Susan Gray, Helena Ong, Richard A. Flavell, Jason K. Kim, Roger J. Davis

Davis Lab Publications

The c-Jun NH(2)-terminal kinase (JNK) interacting protein 1 (JIP1) has been proposed to act as a scaffold protein that mediates JNK activation. However, recent studies have implicated JIP1 in multiple biochemical processes. Physiological roles of JIP1 that are related to the JNK scaffold function of JIP1 are therefore unclear. To test the role of JIP1 in JNK activation, we created mice with a germ line point mutation in the Jip1 gene (Thr(103) replaced with Ala) that selectively blocks JIP1-mediated JNK activation. These mutant mice exhibit a severe defect in JNK activation caused by feeding of a high-fat ...


The Evolution Of Platelet Responses To Collagen Under Conditions Of Hemodynamic Flow, Alec A. Schmaier Aug 2010

The Evolution Of Platelet Responses To Collagen Under Conditions Of Hemodynamic Flow, Alec A. Schmaier

Publicly Accessible Penn Dissertations

Collagen activates platelets through the immune-type GPVI receptor, but the mechanism by which this receptor has adapted to function in platelets under conditions of rapid blood flow is unclear. Additionally, it is unknown if responses to collagen are conserved in nucleated thrombocytes found in non-mammalian vertebrates, which do not express GPVI. Here we show that the GPVI proline-rich domain accelerates GPVI signaling kinetics and is required for maximal adhesion to collagen under flow. The proline-rich domain accelerates signaling through binding and directly activating the Src-family kinase Lyn. Chicken thrombocytes are potently activated by collagen but do not form 3-dimensional aggregates ...


The P38 Mapk Pathway Is Essential For Skeletogenesis And Bone Homeostasis In Mice, Matthew B. Greenblatt, Jae-Hyuck Shim, Weiguo Zou, Despina Sitara, Michelle Schweitzer, Dorothy Hu, Sutada Lotinun, Yasuyo Sano, Roland Baron, Jin Mo Park, Simon Arthur, Min Xie, Michael D. Schneider, Bo Zhai, Steven Gygi, Roger J. Davis, Laurie H. Glimcher Jul 2010

The P38 Mapk Pathway Is Essential For Skeletogenesis And Bone Homeostasis In Mice, Matthew B. Greenblatt, Jae-Hyuck Shim, Weiguo Zou, Despina Sitara, Michelle Schweitzer, Dorothy Hu, Sutada Lotinun, Yasuyo Sano, Roland Baron, Jin Mo Park, Simon Arthur, Min Xie, Michael D. Schneider, Bo Zhai, Steven Gygi, Roger J. Davis, Laurie H. Glimcher

Davis Lab Publications

Nearly every extracellular ligand that has been found to play a role in regulating bone biology acts, at least in part, through MAPK pathways. Nevertheless, much remains to be learned about the contribution of MAPKs to osteoblast biology in vivo. Here we report that the p38 MAPK pathway is required for normal skeletogenesis in mice, as mice with deletion of any of the MAPK pathway member-encoding genes MAPK kinase 3 (Mkk3), Mkk6, p38a, or p38b displayed profoundly reduced bone mass secondary to defective osteoblast differentiation. Among the MAPK kinase kinase (MAP3K) family, we identified TGF-beta-activated kinase 1 (TAK1; also known ...


Distinct Roles Of C-Jun N-Terminal Kinase Isoforms In Neurite Initiation And Elongation During Axonal Regeneration, Monia Barnat, Herve Enslen, Friedrich Propst, Roger J. Davis, Sylvia Soares, Fatiha Nothias Jun 2010

Distinct Roles Of C-Jun N-Terminal Kinase Isoforms In Neurite Initiation And Elongation During Axonal Regeneration, Monia Barnat, Herve Enslen, Friedrich Propst, Roger J. Davis, Sylvia Soares, Fatiha Nothias

Davis Lab Publications

c-Jun N-terminal kinases (JNKs) (comprising JNK1-3 isoforms) are members of the MAPK (mitogen-activated protein kinase) family, activated in response to various stimuli including growth factors and inflammatory cytokines. Their activation is facilitated by scaffold proteins, notably JNK-interacting protein-1 (JIP1). Originally considered to be mediators of neuronal degeneration in response to stress and injury, recent studies support a role of JNKs in early stages of neurite outgrowth, including adult axonal regeneration. However, the function of individual JNK isoforms, and their potential effector molecules, remained unknown. Here, we analyzed the role of JNK signaling during axonal regeneration from adult mouse dorsal root ...


Poisonous Rangeland Plants In San Luis Obispo County, Sara Litten, Amanda Ou Jun 2010

Poisonous Rangeland Plants In San Luis Obispo County, Sara Litten, Amanda Ou

Animal Science

Poisonous Rangeland Plants in San Luis Obispo County is a comprehensive educational guide to rangeland plants that are toxic to domestic livestock. This guide begins with an exploration of how the biological systems are affected by the poisonous plant toxins. The biochemistry behind these toxins is included in the discussion. Next, reference material for fourteen plants that inhabit San Luis Obispo County is provided. This information includes specific toxins found in poisonous plants, affected animals, symptoms of poisoning, stages of growth, lethal dose, and distribution of the plant in California. This section of the guide is filled with helpful photos ...


Analysis Of Apoptosis Of Memory T Cells And Dendritic Cells During The Early Stages Of Viral Infection Or Exposure To Toll-Like Receptor Agonists, Kapil Bahl, Anette Hubner, Roger J. Davis, Raymond M. Welsh May 2010

Analysis Of Apoptosis Of Memory T Cells And Dendritic Cells During The Early Stages Of Viral Infection Or Exposure To Toll-Like Receptor Agonists, Kapil Bahl, Anette Hubner, Roger J. Davis, Raymond M. Welsh

Davis Lab Publications

Profound type I interferon (IFN-I)-dependent attrition of memory CD8 and CD4 T cells occurs early during many infections. It is dramatic at 2 to 4 days following lymphocytic choriomeningitis virus (LCMV) infection of mice and can be elicited by the IFN-inducing Toll receptor agonist poly(I:C). We show that this attrition occurs in many organs, indicating that it is due to T cell loss rather than redistribution. This loss correlated with elevated intracellular staining of T cells ex vivo for activated caspases but with only low levels of ex vivo staining with annexin V, probably due to the ...


Microtubule Stabilization By Bone Morphogenetic Protein Receptor-Mediated Scaffolding Of C-Jun N-Terminal Kinase Promotes Dendrite Formation, Monika Podkowa, Xin Zhao, Chi-Wing Chow, Eleanor T. Coffey, Roger J. Davis, Liliana Attisano May 2010

Microtubule Stabilization By Bone Morphogenetic Protein Receptor-Mediated Scaffolding Of C-Jun N-Terminal Kinase Promotes Dendrite Formation, Monika Podkowa, Xin Zhao, Chi-Wing Chow, Eleanor T. Coffey, Roger J. Davis, Liliana Attisano

Davis Lab Publications

Neuronal outgrowth occurs via coordinated remodeling of the cytoskeleton involving both actin and microtubules. Microtubule stabilization drives the extending neurite, yet little is known of the molecular mechanisms whereby extracellular cues regulate microtubule dynamics. Bone morphogenetic proteins (BMPs) play an important role in neuronal differentiation and morphogenesis, and BMP7 in particular induces the formation of dendrites. Here, we show that BMP7 induces stabilization of microtubules in both a MAP2-dependent neuronal cell culture model and in dendrites of primary cortical neurons. BMP7 rapidly activates c-Jun N-terminal kinases (JNKs), known regulators of microtubule dynamics, and we show that JNKs associate with the ...


Early Vessel Evolution And The Diversification Of Wood Function: Insights From The Malagasy Canellales, Patrick Joseph Hudson May 2010

Early Vessel Evolution And The Diversification Of Wood Function: Insights From The Malagasy Canellales, Patrick Joseph Hudson

Masters Theses

Xylem vessels have long been proposed as a key innovation for the ecological diversification of angiosperms by providing a breakthrough in hydraulic efficiency to support high rates of photosynthesis and growth. However, recent studies demonstrated that angiosperm woods with structurally ‘primitive’ vessels did not have greater whole stem hydraulic capacities as compared to vesselless angiosperms. As an alternative to the hydraulic superiority hypothesis, the heteroxylly hypothesis proposes that subtle hydraulic efficiencies of primitive vessels over tracheids enabled new directions of functional specialization in the wood. However, the functional properties of early heteroxyllous wood remain unknown. We selected the two species ...


The Effects Of Cocaine And Ecstasy On Cardiac Myocytes And The Intact Myocardium, David A. Tiangco Apr 2010

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 ...


C-Jun Nh2-Terminal Kinase Is Required For Lineage-Specific Differentiation But Not Stem Cell Self-Renewal, Ping Xu, Roger J. Davis Mar 2010

C-Jun Nh2-Terminal Kinase Is Required For Lineage-Specific Differentiation But Not Stem Cell Self-Renewal, Ping Xu, Roger J. Davis

Davis Lab Publications

The c-Jun NH(2)-terminal kinase (JNK) is implicated in proliferation. Mice with a deficiency of either the Jnk1 or the Jnk2 genes are viable, but a compound deficiency of both Jnk1 and Jnk2 causes early embryonic lethality. Studies using conditional gene ablation and chemical genetic approaches demonstrate that the combined loss of JNK1 and JNK2 protein kinase function results in rapid senescence. To test whether this role of JNK was required for stem cell proliferation, we isolated embryonic stem (ES) cells from wild-type and JNK-deficient mice. We found that Jnk1(-/-) Jnk2(-/-) ES cells underwent self-renewal, but these cells proliferated ...


Charge Switch Nucleotides, John G. K. Williams, Gregory R. Bashford, Jiyan Chen, Dan Draney, Nara Narayanan, Bambi L. Reynolds, Pamela Sheaff Feb 2010

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.


Role Of The Hypothalamic-Pituitary-Thyroid Axis In Metabolic Regulation By Jnk1, Guadalupe Sabio, Julie Cavanagh-Kyros, Tamera Barrett, Dae Young Jung, Hwi Jin Ko, Helena Ong, Caroline Morel, Alfonso Mora, Judith Reilly, Jason K. Kim, Roger J. Davis Feb 2010

Role Of The Hypothalamic-Pituitary-Thyroid Axis In Metabolic Regulation By Jnk1, Guadalupe Sabio, Julie Cavanagh-Kyros, Tamera Barrett, Dae Young Jung, Hwi Jin Ko, Helena Ong, Caroline Morel, Alfonso Mora, Judith Reilly, Jason K. Kim, Roger J. Davis

Davis Lab Publications

The cJun N-terminal kinase 1 (JNK1) is implicated in diet-induced obesity. Indeed, germline ablation of the murine Jnk1 gene prevents diet-induced obesity. Here we demonstrate that selective deficiency of JNK1 in the murine nervous system is sufficient to suppress diet-induced obesity. The failure to increase body mass is mediated, in part, by increased energy expenditure that is associated with activation of the hypothalamic-pituitary-thyroid axis. Disruption of thyroid hormone function prevents the effects of nervous system JNK1 deficiency on body mass. These data demonstrate that the hypothalamic-pituitary-thyroid axis represents an important target of metabolic signaling by JNK1.


Mechanism Of Catch Force: Tethering Of Thick And Thin Filaments By Twitchin., Thomas M Butler, Marion J Siegman Jan 2010

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 ...


Role Of Muscle C-Jun Nh2-Terminal Kinase 1 In Obesity-Induced Insulin Resistance, Guadalupe Sabio, Norman J. Kennedy, Julie Cavanagh-Kyros, Dae Young Jung, Hwi Jin Ko, Helena Ong, Tamera Barrett, Jason K. Kim, Roger J. Davis Jan 2010

Role Of Muscle C-Jun Nh2-Terminal Kinase 1 In Obesity-Induced Insulin Resistance, Guadalupe Sabio, Norman J. Kennedy, Julie Cavanagh-Kyros, Dae Young Jung, Hwi Jin Ko, Helena Ong, Tamera Barrett, Jason K. Kim, Roger J. Davis

Davis Lab Publications

Obesity caused by feeding of a high-fat diet (HFD) is associated with an increased activation of c-Jun NH(2)-terminal kinase 1 (JNK1). Activated JNK1 is implicated in the mechanism of obesity-induced insulin resistance and the development of metabolic syndrome and type 2 diabetes. Significantly, Jnk1(-)(/)(-) mice are protected against HFD-induced obesity and insulin resistance. Here we show that an ablation of the Jnk1 gene in skeletal muscle does not influence HFD-induced obesity. However, muscle-specific JNK1-deficient (M(KO)) mice exhibit improved insulin sensitivity compared with control wild-type (M(WT)) mice. Thus, insulin-stimulated AKT activation is suppressed in muscle, liver, and ...


Functional Cooperation Of The Proapoptotic Bcl2 Family Proteins Bmf And Bim In Vivo, Anette Hubner, Julie Cavanagh-Kyros, Mercedes Rincon, Richard Flavell, Roger J. Davis Jan 2010

Functional Cooperation Of The Proapoptotic Bcl2 Family Proteins Bmf And Bim In Vivo, Anette Hubner, Julie Cavanagh-Kyros, Mercedes Rincon, Richard Flavell, Roger J. Davis

Davis Lab Publications

Bcl2-modifying factor (Bmf) is a member of the BH3-only group of proapoptotic proteins. To test the role of Bmf in vivo, we constructed mice with a series of mutated Bmf alleles that disrupt Bmf expression, prevent Bmf phosphorylation by the c-Jun NH(2)-terminal kinase (JNK) on Ser(74), or mimic Bmf phosphorylation on Ser(74). We report that the loss of Bmf causes defects in uterovaginal development, including an imperforate vagina and hydrometrocolpos. We also show that the phosphorylation of Bmf on Ser(74) can contribute to a moderate increase in levels of Bmf activity. Studies of compound mutants ...


A Specific Regulatory Role For Sgtα On The Maturation And Activation Of Steroid Hormone Receptors, Atanu Paul Jan 2010

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 ...


A Bird’S-Eye View On The Function Of Sleep, Charles Amlaner, Niels Rattenborg Dec 2009

A Bird’S-Eye View On The Function Of Sleep, Charles Amlaner, Niels Rattenborg

Charles J. Amlaner

Sleep has been detected in every animal that has been adequately studied (Cirelli & Tononi, 2008). The ubiquitous nature of sleep suggests that it evolved early in the course of evolution and therefore may serve a conserved function essential to all animals. This hypothesis forms the rationale behind the development of “simple” animal models of sleep (Allada & Siegel, 2008; Mignot, 2008). By studying sleep in animals such as the fruit fly (Drosophila melanogaster), where the power of genetic techniques can be readily employed,we may gain insight into the initial (perhaps cellular) function of sleep, a function that may still be relevant to understanding sleep in humans. Indeed, recent studies have already demonstrated remarkable similarities between sleep in Drosophila and sleep in mammals (Hendricks, Finn, Panckeri, et al., 2000; Shaw, Cirelli, Greenspan, et al., 2000; reviewed in Cirelli & Bushey, 2008). Although the utility of studying sleep in“simple”animal models is undeniable, it is unlikely that this approach alone will tell the whole story, especially given that Drosophilado not exhibit brain states comparable to mammalian slow-wave sleep (SWS) and rapid eye-movement (REM) sleep (Cirelli, 2006; Cirelli & Bushey, 2008; Hendricks & Sehgal, 2004; Nitz, van Swinderen, Tononi, et al ...