You searched for +publisher:"Vanderbilt University" +contributor:("Heidi E. Hamm").
Showing records 1 – 11 of
11 total matches.
No search limiters apply to these results.
Vanderbilt University
1.
Alexander, Nathan Scott.
Protein structure elucidation from computational techniques and sparse EPR data.
Degree: PhD, Chemistry, 2012, Vanderbilt University
URL: http://hdl.handle.net/1803/13182 
► Computational methods that allow application of electron paramagnetic resonance (EPR) spectroscopy data for protein structure prediction were developed. An implicit cone-model for the spin label…
(more)
▼ Computational methods that allow application of electron paramagnetic resonance (EPR) spectroscopy data for protein structure prediction were developed. An implicit cone-model for the spin label enabled EPR distance information to be incorporated into structure prediction methods. The small, soluble proteins T4-lysozyme and αA-crystallin were used to demonstrate the ability of EPR measurements to guide atomic-detail protein structure prediction. In addition, a spin label rotamer library was developed and incorporated into Rosetta, allowing structural interpretation of distances and dynamics observed through EPR. These methods were applied to investigate the overall structure of the GPCR rhodopsin in complex with the conjugate G-protein transducin, as well as de novo protein structure prediction of membrane proteins. The results show the ability to utilize data from EPR to aid in the prediction of membrane protein structures approaching atomic-detail accuracy. In addition, significant conformational changes were predicted to occur as transducin binds to rhodopsin, and the formation and disruption of stabilizing residue interactions were mapped according to Rosetta energy changes.
Advisors/Committee Members: Michael P. Stone (committee member), Terry P. Lybrand (committee member), Heidi E. Hamm (committee member), Jens Meiler (Committee Chair).
Subjects/Keywords: protein structure prediction; spin label; EPR; structural biology
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alexander, N. S. (2012). Protein structure elucidation from computational techniques and sparse EPR data. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/13182
Chicago Manual of Style (16th Edition):
Alexander, Nathan Scott. “Protein structure elucidation from computational techniques and sparse EPR data.” 2012. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/13182.
MLA Handbook (7th Edition):
Alexander, Nathan Scott. “Protein structure elucidation from computational techniques and sparse EPR data.” 2012. Web. 19 Jan 2021.
Vancouver:
Alexander NS. Protein structure elucidation from computational techniques and sparse EPR data. [Internet] [Doctoral dissertation]. Vanderbilt University; 2012. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/13182.
Council of Science Editors:
Alexander NS. Protein structure elucidation from computational techniques and sparse EPR data. [Doctoral Dissertation]. Vanderbilt University; 2012. Available from: http://hdl.handle.net/1803/13182
Vanderbilt University
2.
Li, Xin.
Roles of adhesion G protein-coupled receptors during zebrafish gastrulation and neuronal migration.
Degree: PhD, Neuroscience, 2013, Vanderbilt University
URL: http://hdl.handle.net/1803/13741
► Gastrulation is a fundamental process during embryogenesis when the germ layers and shape of the animal are generated. Although the major cell movements during gastrulation…
(more)
▼ Gastrulation is a fundamental process during embryogenesis when the germ layers and shape of the animal are generated. Although the major cell movements during gastrulation have been characterized, the underlying cellular and molecular mechanisms are only beginning to be understood. Identifying new molecules regulating gastrulation and studying their interactions with known regulators of gastrulation will bring us closer to a full mechanistic understanding of this key developmental process.
In this study, I investigated the potential roles of the adhesion G protein-coupled receptor (GPCR) family during gastrulation. Among 30 annotated or partially annotated adhesion GPCRs in the sequenced zebrafish genome, the four members comprising the Group IV adhesion GPCR subfamily exhibit distinct and dynamic expression patterns during embryogenesis. Therefore, I performed functional analyses of members from this subfamily during embryogenesis. Interfering with Gpr124 function caused defects in multiple tissues in the caudal region of the embryo, including the notochord and vasculature, which warrant future studies on the mechanism of Gpr124 function.
Central to this thesis, I uncovered a role for Gpr125 during convergence and extension (C&
E) gastrulation movements and facial branchiomotor neuron (FBMN) migration. Consistent with a potential role during gastrulation, I showed gpr125 is expressed maternally and at blastula and gastrula stages. Excess Gpr125 in wild-type embryos impaired C&
E movements and the underlying cellular and molecular polarities. Whereas interfering with Gpr125 function alone did not affect development, it exacerbated the C&
E and FBMN migration defects of embryos with reduced Wnt/planar cell polarity (PCP) signaling. At the cellular level, Gpr125 depletion enhanced the disruption of polarized cell behaviors in embryos heterozygous and homozygous for trilobite/vang-like 2 (tri/vangl2) Wnt/PCP gene. At the molecular level, Gpr125 recruited Dishevelled (Dvl), the signaling hub of Wnt/PCP pathway, to the cell membrane, which fulfils the prerequisite for Wnt/PCP activation. Moreover, Gpr125 and Dvl mutually clustered with one another to form discrete membrane subdomains, and the Gpr125 intracellular domain directly interacted with Dvl in pull-down assays. Intriguingly, Dvl and Gpr125 were able to recruit a subset of PCP components into membrane subdomains, suggesting that Gpr125 may modulate the composition of Wnt/PCP membrane complexes. This study reveals a role for Gpr125 in Wnt/PCP mediated processes and provides mechanistic insight into Gpr125 function and Wnt/PCP signaling.
Advisors/Committee Members: Heidi E. Hamm (committee member), Lilianna Solnica-Krezel (committee member), Christopher J. Janetopoulos (committee member), Joshua T. Gamse (Committee Chair).
Subjects/Keywords: FBMN; Gpr124; Gpr125; Dvl; wnt11; Vangl2; scribble; Wnt/PCP pathway
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, X. (2013). Roles of adhesion G protein-coupled receptors during zebrafish gastrulation and neuronal migration. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/13741
Chicago Manual of Style (16th Edition):
Li, Xin. “Roles of adhesion G protein-coupled receptors during zebrafish gastrulation and neuronal migration.” 2013. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/13741.
MLA Handbook (7th Edition):
Li, Xin. “Roles of adhesion G protein-coupled receptors during zebrafish gastrulation and neuronal migration.” 2013. Web. 19 Jan 2021.
Vancouver:
Li X. Roles of adhesion G protein-coupled receptors during zebrafish gastrulation and neuronal migration. [Internet] [Doctoral dissertation]. Vanderbilt University; 2013. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/13741.
Council of Science Editors:
Li X. Roles of adhesion G protein-coupled receptors during zebrafish gastrulation and neuronal migration. [Doctoral Dissertation]. Vanderbilt University; 2013. Available from: http://hdl.handle.net/1803/13741
Vanderbilt University
3.
Betke, Katherine Michelle.
Investigating The Role of G protein βγ Specificity In Modulation of Synaptic Transmission.
Degree: PhD, Pharmacology, 2014, Vanderbilt University
URL: http://hdl.handle.net/1803/12808
► Synaptic transmission is characterized by exocytotic events which mediate the release of chemical transmitters to facilitate neuronal communication. Inhibitory presynaptic GPCRs act as feedback regulators…
(more)
▼ Synaptic transmission is characterized by exocytotic events which mediate the release of chemical transmitters to facilitate neuronal communication. Inhibitory presynaptic GPCRs act as feedback regulators limiting transmitter release from presynaptic terminals via the actions of their Gβγ subunits. Although Gβγ subunits have been shown to regulate exocytosis through direct interaction with the exocytotic machinery, relatively little is known about which G protein heterotrimers exist in vivo, the specificity of this interaction or its physiological consequences. The hypothesis proposed in the present study is that endogenous Gβγ subunits exhibit specificity when interacting with SNARE proteins to modulate synaptic transmission. To address this, efforts were made to examine the expression of different G protein isoforms throughout the CNS, study the functional specificity of α2A adrenergic receptor mediated Gβγ/SNARE interactions, and develop compounds which would allow its modulation. Targeted proteomics studies demonstrated a wide distribution of most G protein isoforms across brain regions and at synaptic terminals with distinct localization patterns observed for different Gβ and Gγ subunits. Investigation into the functional selectivity of SNARE modulation revealed that α2A adrenergic receptors exhibit specificity when interacting with Gβγ subunits as only a subset of Gβ and Gγ isoforms were coimmunoprecipitated with the receptor following stimulation. Further, lead compounds were developed which had an effect on the Gβγ/SNARE interaction, suggesting it may be possible to target this association directly through the use of selective protein-protein modulators. Taken together, the data presented in this study contribute to a better understanding of G protein signaling within the CNS as well as the role of specificity in α2A adrenergic receptor modulation of SNARE function.
Advisors/Committee Members: Kevin Currie (committee member), Kevin Schey (committee member), Heidi E. Hamm (committee member), Danny Winder (committee member), P. Jeffrey Conn (Committee Chair).
Subjects/Keywords: proteomics; synaptic transmission; G protein isoforms; SNARE; multiple reaction monitoring; α2A adrenergic receptor; exocytosis; G protein; Gβγ
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Betke, K. M. (2014). Investigating The Role of G protein βγ Specificity In Modulation of Synaptic Transmission. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12808
Chicago Manual of Style (16th Edition):
Betke, Katherine Michelle. “Investigating The Role of G protein βγ Specificity In Modulation of Synaptic Transmission.” 2014. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/12808.
MLA Handbook (7th Edition):
Betke, Katherine Michelle. “Investigating The Role of G protein βγ Specificity In Modulation of Synaptic Transmission.” 2014. Web. 19 Jan 2021.
Vancouver:
Betke KM. Investigating The Role of G protein βγ Specificity In Modulation of Synaptic Transmission. [Internet] [Doctoral dissertation]. Vanderbilt University; 2014. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/12808.
Council of Science Editors:
Betke KM. Investigating The Role of G protein βγ Specificity In Modulation of Synaptic Transmission. [Doctoral Dissertation]. Vanderbilt University; 2014. Available from: http://hdl.handle.net/1803/12808
Vanderbilt University
4.
Young, Summer Elizabeth.
Modulation of thrombin receptor signaling.
Degree: PhD, Pharmacology, 2013, Vanderbilt University
URL: http://hdl.handle.net/1803/14534
► The platelet thrombin receptors Protease-activated receptor 1 (PAR1) and Protease activated receptor 4 (PAR4) stand at the intersection of coagulation and platelet activation. Thrombin receptors…
(more)
▼ The platelet thrombin receptors Protease-activated receptor 1 (PAR1) and Protease activated receptor 4 (PAR4) stand at the intersection of coagulation and platelet activation. Thrombin receptors are thus excellent pharmacological targets for the prevention of thrombosis. PAR1 antagonists show promise in clinical trials for the prevention of stroke, myocardial infarction, and death. However, like all anti-platelet therapeutics, PAR1 antagonism carries an increased risk for bleeding. PAR4, the low affinity thrombin receptor, is the next logical target. However, the field lacks a good pharmacological probe thus the role of PAR4 in thrombosis remains unknown.
Described herein is the characterization of modulators of thrombin receptor signaling by distinct entities. The modulation of PAR1 by Activated protein C, though intriguing, fails to differ from thrombin mediated PAR1 activation. Optimization of a high-throughput screen for novel PAR1 antagonists yielded novel structures for the development of future PAR1 inhibitory compounds. One inhibitory compound, o,p ddd, was found to not only inhibit PAR1 but also PAR4 and collagen mediated platelet activation through complex mechanisms. In addition, the design, synthesis, and characterization of indole based, selective PAR4 antagonists is also described.
Approved: Professor
Heidi E.
Hamm
Advisors/Committee Members: H. Alex Brown (committee member), P. Jeffrey Conn (committee member), Kathleen L. Gould (committee member), Craig W. Lindsley (committee member), Heidi E. Hamm (committee member), John A. Oates (committee member), Richard M. Breyer (Committee Chair).
Subjects/Keywords: protease-activated receptor; thrombosis; thrombin receptors
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Young, S. E. (2013). Modulation of thrombin receptor signaling. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14534
Chicago Manual of Style (16th Edition):
Young, Summer Elizabeth. “Modulation of thrombin receptor signaling.” 2013. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/14534.
MLA Handbook (7th Edition):
Young, Summer Elizabeth. “Modulation of thrombin receptor signaling.” 2013. Web. 19 Jan 2021.
Vancouver:
Young SE. Modulation of thrombin receptor signaling. [Internet] [Doctoral dissertation]. Vanderbilt University; 2013. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/14534.
Council of Science Editors:
Young SE. Modulation of thrombin receptor signaling. [Doctoral Dissertation]. Vanderbilt University; 2013. Available from: http://hdl.handle.net/1803/14534
Vanderbilt University
5.
Oliver, Kendra Helen.
Novel implications of lost serotonin transporter function on platelet biology.
Degree: PhD, Pharmacology, 2016, Vanderbilt University
URL: http://hdl.handle.net/1803/13914
► Reduced platelet aggregation and a mild bleeding phenotype has been observed in patients chronically taking selective serotonin reuptake inhibitors (SSRIs) that block the serotonin transporter…
(more)
▼ Reduced platelet aggregation and a mild bleeding phenotype has been observed in patients chronically taking selective serotonin reuptake inhibitors (SSRIs) that block the serotonin transporter (SERT). Here, I explore this relationship between platelet activation, specifically αIIbβ3 activation, and the loss of SERT function. First, using a pharmacological approach, we investigate the role of acute loss of SERT function on platelet αIIbβ3 activation. We find that acute treatment with SSRIs does not alter αIIbβ3 activation but reduced αIIbβ3-mediated platelet spreading. Next, two models of sustained loss of SERT function were used to investigate platelet αIIbβ3 activation; the SERT knockout mouse (SERT-/-) mice and mice treated with citalopram for 6-days. Both models replicate the mild bleeding phenotypes noted in human patients taking SSRIs. Following transfusion of wild-type platelets into SERT-/- mice, SERT-/- bleeding times were reduced to WT levels suggesting defects in platelet function. We examined αIIbβ3 activation (JON/A binding) and granule exocytosis with P-selectin surface expression (CD62p binding) following ADP stimulation and found reduced ADP-mediated αIIbβ3 activation in SERT-/- platelets. Acute treatment of platelets with SSRIs (paroxetine and citalopram) to prevent serotonin uptake during activation did not alter ADP-mediated αIIbβ3 activation. However, 5HT2AR antagonists significantly reduced ADP-mediated αIIbβ3 activation. These findings suggest that serotonin synergizes with ADP through 5HT2AR activation, but not acute SERT uptake. Furthermore, SERT-/- platelets displayed reduced serotonin enhanced ADP-mediated αIIbβ3 activation, likely due to reduced 5HT2AR cell surface levels. This again suggests acute function of SERT does not alter ADP-mediated αIIbβ3 activation but that sustained loss of SERT function alters surface expression of 5HT2AR and ultimately reduces ADP-mediated αIIbβ3 activation. Lastly, I discuss the hypercoaguability phenotype of the β3 integrin mutation, which models the human PIA2 polymorphism. This mutation leads to a primed αIIbβ3 integrin characterized by increased baseline Src-signaling. The hypercoaguability phenotype can be rescued with the Src inhibitor SKI606 but, interestingly, is also hyperserotonergic. We find that blockage of the SERT transporter with 6-day citalopram treatment is also able to rescue the KI thrombin clotting time. These findings further establish a connection between serotonergic regulation and αIIbβ3 activation in platelet function. This body of work expands the current knowledge of serotonin in platelet biology and supports a more physiologically based understanding of the effects of SSRIs on platelet function.
Advisors/Committee Members: Heidi E. Hamm, Ph.D. (committee member), Ana M.D. Carneiro, Ph.D. (committee member), Digna R. Velez Edwards Ph.D., M.S. (committee member), Vsevolod Gurevich, Ph.D. (committee member), Jonathan Schoenecker, M.D., Ph.D. (Committee Chair).
Subjects/Keywords: platelet; SERT; serotonin; 5HT2AR
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Oliver, K. H. (2016). Novel implications of lost serotonin transporter function on platelet biology. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/13914
Chicago Manual of Style (16th Edition):
Oliver, Kendra Helen. “Novel implications of lost serotonin transporter function on platelet biology.” 2016. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/13914.
MLA Handbook (7th Edition):
Oliver, Kendra Helen. “Novel implications of lost serotonin transporter function on platelet biology.” 2016. Web. 19 Jan 2021.
Vancouver:
Oliver KH. Novel implications of lost serotonin transporter function on platelet biology. [Internet] [Doctoral dissertation]. Vanderbilt University; 2016. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/13914.
Council of Science Editors:
Oliver KH. Novel implications of lost serotonin transporter function on platelet biology. [Doctoral Dissertation]. Vanderbilt University; 2016. Available from: http://hdl.handle.net/1803/13914
Vanderbilt University
6.
Stevens, David Michael.
Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery.
Degree: PhD, Pharmacology, 2014, Vanderbilt University
URL: http://hdl.handle.net/1803/12424
► PHARMACOLOGY Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery David Michael Stevens Dissertation under the direction of Professor Eva M. Harth Solubility remains the…
(more)
▼ PHARMACOLOGY
Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery
David Michael Stevens
Dissertation under the direction of Professor Eva M. Harth
Solubility remains the biggest obstacle in the development of new therapeutics and is the primary cause for clinical failure of promising drugs. The high lipophilicity of many chemotherapeutics and peptides imposes a major challenge for systemic administration and drug efficacy. Recent interest of pharmaceutical companies to apply nanoformulations stems from the interest to improve solubility, specificity, and efficacy for current, off-patent, and shelved drugs rather than creating new therapies. Numerous approaches have been investigated including poly(lactic-co-glycolic acid) (PLGA) formulations, lipid-based micelles, and pegylation of proteins, but these efforts often fall short of expectations due to rapid drug release, the use of non-degradable materials, and accumulation and toxicity in the liver. To overcome these obstacles, practical approaches have been developed for the formation of biodegradable nanoparticles and hydrogels via crosslinking reactions. Polyester nanoparticles, or “nanosponges,” are degradable, biocompatible networks synthesized using developed intermolecular crosslinking chemistries and are capable of encapsulating the therapeutic while enhancing the drug’s solubility in aqueous solution, and the crosslinking density of the nanosponge can be adjusted to allow customized drug release rates. The availability of functionalities such as allyl and amine groups on the surface of the particles allows for targeting ligand attachment for targeted drug delivery applications. Having the abilities of organ-specific delivery and adjustable drug release rates allows the tailoring of this drug delivery platform to meet the specific needs of various applications. The same concept of using crosslinking chemistries to form nanosponges can be used to form hydrogel materials under concentrated conditions, and these biodegradable hydrogels are capable of tunable swelling, drug encapsulation, and adjustable drug release rates. Methods to synthesize predictable and defined polymer precursors have been developed which allows for complete customization of the resulting nanosponges and hydrogels that can be used for various applications including cancer, diabetes, and bone healing.
Approved _________________________________________________ Date_________
Eva M. Harth, Ph.D.
Advisors/Committee Members: Heidi E. Hamm (committee member), Craig W. Lindsley (committee member), Eva M. Harth (committee member), W. Scott Akers (committee member), Joey V. Barnett (Committee Chair).
Subjects/Keywords: drug delivery; nanoparticles; Pharmacology; polymer chemistry
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Stevens, D. M. (2014). Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12424
Chicago Manual of Style (16th Edition):
Stevens, David Michael. “Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery.” 2014. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/12424.
MLA Handbook (7th Edition):
Stevens, David Michael. “Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery.” 2014. Web. 19 Jan 2021.
Vancouver:
Stevens DM. Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery. [Internet] [Doctoral dissertation]. Vanderbilt University; 2014. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/12424.
Council of Science Editors:
Stevens DM. Nanonetworks as Innovative Platforms for Therapeutic Solubilization and Delivery. [Doctoral Dissertation]. Vanderbilt University; 2014. Available from: http://hdl.handle.net/1803/12424
Vanderbilt University
7.
Bruntz, Ronald Chase.
Insights into the Molecular Mechanisms of Phospholipase D-Mediated Cancer Cell Survival.
Degree: PhD, Pharmacology, 2014, Vanderbilt University
URL: http://hdl.handle.net/1803/10427
► The production of bioactive lipids by phospholipases has long been appreciated as an important mode of cellular communication. Phospholipase D (PLD) enzymes hydrolyze phosphatidylcholine to…
(more)
▼ The production of bioactive lipids by phospholipases has long been appreciated as an important mode of cellular communication. Phospholipase D (PLD) enzymes hydrolyze phosphatidylcholine to generate a choline headgroup and the important lipid second messenger, phosphatidic acid (PtdOH). PLD family members are found in a diverse range of species from viruses to humans and regulate many important physiological processes including cytoskeletal rearrangements, cell migration, immune response, and cell proliferation. As such, PLD promotes oncogenic processes and elevated PLD activity has been documented in many types of cancerous tissue and derived cell lines. PLD activity is associated with cell cycle progression, resistance to apoptotic stimuli, and tumor cell invasion, but the molecular mechanisms of these PLD-mediated processes are largely uncharacterized. The goal of this project was to identify and characterize novel PLD-protein complexes in order to further understand the mechanisms by which PLD promotes cancer growth and survival. In this dissertation, PLD-derived PtdOH is demonstrated to be a novel regulator of pro-survival Akt kinase in glioblastoma cells by regulating membrane recruitment and activation of Akt. Inhibition of PLD enzymatic activity and subsequent Akt activation decreases GBM cell viability by specifically inhibiting autophagic flux. Additionally, PLD is shown to interact with a number of metabolic enzymes and a potential role for the regulation of cellular bioenergetics in GBM is explored. The results of this research provide mechanistic insight into PLD-mediated cancer cell survival.
Advisors/Committee Members: Brian E. Wadzinski (committee member), Daniel C. Liebler (committee member), H. Alex Brown (committee member), Heidi E. Hamm (committee member), Kevin C. Ess (committee member), John H. Exton (Committee Chair).
Subjects/Keywords: phospholipase D; phosphatidic acid; cancer; Akt; cell signaling; autophagy
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bruntz, R. C. (2014). Insights into the Molecular Mechanisms of Phospholipase D-Mediated Cancer Cell Survival. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10427
Chicago Manual of Style (16th Edition):
Bruntz, Ronald Chase. “Insights into the Molecular Mechanisms of Phospholipase D-Mediated Cancer Cell Survival.” 2014. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/10427.
MLA Handbook (7th Edition):
Bruntz, Ronald Chase. “Insights into the Molecular Mechanisms of Phospholipase D-Mediated Cancer Cell Survival.” 2014. Web. 19 Jan 2021.
Vancouver:
Bruntz RC. Insights into the Molecular Mechanisms of Phospholipase D-Mediated Cancer Cell Survival. [Internet] [Doctoral dissertation]. Vanderbilt University; 2014. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/10427.
Council of Science Editors:
Bruntz RC. Insights into the Molecular Mechanisms of Phospholipase D-Mediated Cancer Cell Survival. [Doctoral Dissertation]. Vanderbilt University; 2014. Available from: http://hdl.handle.net/1803/10427
Vanderbilt University
8.
Cleghorn, Whitney Marie.
Arrestins regulate cell spreading and motility via focal adhesion dynamics.
Degree: PhD, Pharmacology, 2012, Vanderbilt University
URL: http://hdl.handle.net/1803/12660
► Arrestins bind G protein-coupled receptors and more than 100 non-receptor partners, regulating various signaling pathways and cellular functions. The interactions of many proteins (e.g., Src,…
(more)
▼ Arrestins bind G protein-coupled receptors and more than 100 non-receptor partners, regulating various signaling pathways and cellular functions. The interactions of many proteins (
e.g., Src, JNK3, ERK½, Mdm2, etc.) with receptor-bound arrestin localize these molecules to receptor-rich membranes. Our recent finding that arrestins bind microtubules and recruit signaling proteins to the cytoskeleton prompted us to investigate whether arrestins affect cell motility and morphology. Here we describe a novel function of arrestins, their direct effect on focal adhesion dynamics. We demonstrate excessive spreading of cells lacking both non-visual arrestins, which is substrate-independent, evident on both fibronectin and poly-D-lysine. Reduced activity of small GTPases RhoA and Rac1 in arrestin-deficient cells is only partially responsible for the cell spreading phenotype. Increased adhesion, reflected by elevated activity of focal adhesion proteins paxillin and focal adhesion kinase, underlies the exaggerated spreading of arrestin-null cells and their reduced motility. The absence of arrestins greatly increases the size and lifespan of focal adhesions, indicating that arrestins are necessary for rapid focal adhesion turnover. Focal adhesions in arrestin-deficient cells are insensitive to microtubules, suggesting that arrestins likely mediate the induction of focal adhesion disassembly upon microtubule regrowth. Overexpression of WT arrestins and their receptor binding-deficient mutants in arrestin-null cells rescues the phenotype, demonstrating that regulation of focal adhesion dynamics by arrestins is receptor-independent. This is the first demonstration that arrestins play a direct role in focal adhesion dynamics.
Advisors/Committee Members: Roy Zent (committee member), Heidi E. Hamm (committee member), Vsevolod V. Gurevich (committee member), Alissa M. Weaver (committee member), Brian E. Wadzinski (Committee Chair).
Subjects/Keywords: structural biology; pharmacology; morphology; cell biology; GPCR; arrestin
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cleghorn, W. M. (2012). Arrestins regulate cell spreading and motility via focal adhesion dynamics. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12660
Chicago Manual of Style (16th Edition):
Cleghorn, Whitney Marie. “Arrestins regulate cell spreading and motility via focal adhesion dynamics.” 2012. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/12660.
MLA Handbook (7th Edition):
Cleghorn, Whitney Marie. “Arrestins regulate cell spreading and motility via focal adhesion dynamics.” 2012. Web. 19 Jan 2021.
Vancouver:
Cleghorn WM. Arrestins regulate cell spreading and motility via focal adhesion dynamics. [Internet] [Doctoral dissertation]. Vanderbilt University; 2012. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/12660.
Council of Science Editors:
Cleghorn WM. Arrestins regulate cell spreading and motility via focal adhesion dynamics. [Doctoral Dissertation]. Vanderbilt University; 2012. Available from: http://hdl.handle.net/1803/12660
Vanderbilt University
9.
Carrington, Sheridan Jared S.
Differential Glycosylation of the Inwardly Rectifying Potassium Channel Kir7.1 by G protein-coupled Receptors.
Degree: PhD, Molecular Physiology and Biophysics, 2019, Vanderbilt University
URL: http://hdl.handle.net/1803/10914
► Kir7.1 is an inwardly rectifying potassium channel with important roles in the regulation of the membrane potential in retinal pigment epithelium, uterine smooth muscle, and…
(more)
▼ Kir7.1 is an inwardly rectifying potassium channel with important roles in the regulation of the membrane potential in retinal pigment epithelium, uterine smooth muscle, and hypothalamic neurons. Regulation of G protein–coupled inwardly rectifying potassium (GIRK) channels by G protein–coupled receptors (GPCRs) via the G protein beta gamma subunits has been well characterized. However, how Kir channels are regulated is incompletely understood. We report here that Kir7.1 is also regulated by GPCRs, but through a different mechanism. Using Western blot analysis, we observed that multiple GPCRs tested caused a striking reduction in the complex glycosylation of Kir7.1. Further, GPCR-mediated reduction of Kir7.1 glycosylation in HEK293T cells did not alter its expression at the cell surface but decreased channel activity. Of note, mutagenesis of the sole Kir7.1 glycosylation site reduced conductance and open probability, as indicated by single-channel recording. Additionally, we report that the L241P mutation of Kir7.1 associated with Lebers congenital amaurosis (LCA), an inherited retinal degenerative disease has significantly reduced complex glycosylation. Collectively, these results suggest that Kir7.1 channel glycosylation is essential for function, and this activity within cells is suppressed by most GPCRs. The Melanocortin 4 receptor (MC4R), a GPCR previously reported to induce ligand-regulated activity of this channel, is the only GPCR tested that does not have this effect on Kir7.1.
Advisors/Committee Members: Jerod S. Denton, Ph.D. (committee member), Heidi E. Hamm, Ph.D. (committee member), Anne K. Kenworthy, Ph.D. (committee member), David A. Jacobson, Ph.D. (committee member), Advisor: Roger D. Cone, Ph.D. (committee member), Roger J. Colbran, Ph.D. (Committee Chair).
Subjects/Keywords: GPCR; ion channel; kir; glycosylation; ion channel; potassium channel
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Carrington, S. J. S. (2019). Differential Glycosylation of the Inwardly Rectifying Potassium Channel Kir7.1 by G protein-coupled Receptors. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10914
Chicago Manual of Style (16th Edition):
Carrington, Sheridan Jared S. “Differential Glycosylation of the Inwardly Rectifying Potassium Channel Kir7.1 by G protein-coupled Receptors.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/10914.
MLA Handbook (7th Edition):
Carrington, Sheridan Jared S. “Differential Glycosylation of the Inwardly Rectifying Potassium Channel Kir7.1 by G protein-coupled Receptors.” 2019. Web. 19 Jan 2021.
Vancouver:
Carrington SJS. Differential Glycosylation of the Inwardly Rectifying Potassium Channel Kir7.1 by G protein-coupled Receptors. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/10914.
Council of Science Editors:
Carrington SJS. Differential Glycosylation of the Inwardly Rectifying Potassium Channel Kir7.1 by G protein-coupled Receptors. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://hdl.handle.net/1803/10914
Vanderbilt University
10.
Oldham, William Michael.
Mapping Conformational Changes Along the Activation Pathway of the Heterotrimeric G Protein α Subunit with Site-directed Spin-labeling.
Degree: PhD, Pharmacology, 2008, Vanderbilt University
URL: http://hdl.handle.net/1803/12040
► Heterotrimeric G proteins act as molecular switches in signaling pathways by coupling the activation of heptahelical receptors at the cell surface to intracellular responses. These…
(more)
▼ Heterotrimeric G proteins act as molecular switches in signaling pathways by coupling the activation of heptahelical receptors at the cell surface to intracellular responses. These receptors bind to and activate G proteins by catalyzing GTP for GDP exchange on the Gα subunit, leading to a structural change in Gα(GTP) and Gβγ subunits that allows the activation of a variety of downstream effector proteins. Despite its crucial role in a variety of signal transduction pathways, relatively little is known about the structure of the receptor-G protein complex and how this interaction leads to GDP release from Gα. Thus, the primary goal of this research has been to use the biophysical technique of site-directed spin-labeling to identify and characterize receptor-dependent conformational changes in Gα with electron paramagnetic resonance spectroscopy. With this approach, α5 helix of Gα has been shown to play a key role in coupling receptor-binding to GDP release. In addition, the structure and dynamics of several other important regions of this protein have been explored throughout the G protein activation pathway. These studies enhance the current understanding of G protein structure and function, which has been largely based on high resolution structural data from x-ray crystallography, by providing dynamic information about this protein in solution. This combination of structural approaches should continue to provide important insight into the biomechanics of G protein signaling and will hopefully serve as the starting point for more sophisticated models of the critically important receptor-G protein complex.
Advisors/Committee Members: Jeff Conn (committee member), Hassane Mchaourab (committee member), Heidi E. Hamm (committee member), Vsevolod Gurevich (Committee Chair).
Subjects/Keywords: heterotrimer; GPCR; rhodopsin; transducin
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Oldham, W. M. (2008). Mapping Conformational Changes Along the Activation Pathway of the Heterotrimeric G Protein α Subunit with Site-directed Spin-labeling. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12040
Chicago Manual of Style (16th Edition):
Oldham, William Michael. “Mapping Conformational Changes Along the Activation Pathway of the Heterotrimeric G Protein α Subunit with Site-directed Spin-labeling.” 2008. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/12040.
MLA Handbook (7th Edition):
Oldham, William Michael. “Mapping Conformational Changes Along the Activation Pathway of the Heterotrimeric G Protein α Subunit with Site-directed Spin-labeling.” 2008. Web. 19 Jan 2021.
Vancouver:
Oldham WM. Mapping Conformational Changes Along the Activation Pathway of the Heterotrimeric G Protein α Subunit with Site-directed Spin-labeling. [Internet] [Doctoral dissertation]. Vanderbilt University; 2008. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/12040.
Council of Science Editors:
Oldham WM. Mapping Conformational Changes Along the Activation Pathway of the Heterotrimeric G Protein α Subunit with Site-directed Spin-labeling. [Doctoral Dissertation]. Vanderbilt University; 2008. Available from: http://hdl.handle.net/1803/12040
Vanderbilt University
11.
Henage, Lee Gardner.
Kinetic analysis of phospholipase D: Allosteric modulation by monomeric GTPases, protein kinase C, and polyphosphoinositides.
Degree: PhD, Pharmacology, 2006, Vanderbilt University
URL: http://hdl.handle.net/1803/10502
► In mammalian cells, phospholipase D activity is tightly regulated by diverse cellular signals including hormones, neurotransmitters, and growth factors. Multiple signaling pathways converge upon phospholipase…
(more)
▼ In mammalian cells, phospholipase D activity is tightly regulated by diverse cellular signals including hormones, neurotransmitters, and growth factors. Multiple signaling pathways converge upon phospholipase D to modulate cellular actions such as cell growth, shape and secretion. The kinetic properties of protein kinase C and G-protein regulation of mammalian phospholipase D1 (PLD1) were examined in order to better understand interactions between PLD1 and its regulators. Activation by Arf-1, RhoA, Rac1, Cdc42, protein kinase Ca, and phosphatidylinositol 4,5-bisphosphate displayed surface dilution kinetics, but these effectors modulated different kinetic parameters. A kinetic description of PLD1 activation by multiple modulators reveals a mechanism for apparent synergy between activators. These findings suggest a role for PLD1 as a signaling node, in which integration of convergent signals occurs within discrete locales of the cellular membrane.
Advisors/Committee Members: Heidi E. Hamm (committee member), Terry R. Lybrand (committee member), Albert H. Beth (committee member), John H. Exton (committee member), H. Alex Brown (committee member), Vsevolod V. Gurevich (Committee Chair).
Subjects/Keywords: phospholipase d; enzymology; G-protein; protein kinase C; ADP-ribosylation factor
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Henage, L. G. (2006). Kinetic analysis of phospholipase D: Allosteric modulation by monomeric GTPases, protein kinase C, and polyphosphoinositides. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10502
Chicago Manual of Style (16th Edition):
Henage, Lee Gardner. “Kinetic analysis of phospholipase D: Allosteric modulation by monomeric GTPases, protein kinase C, and polyphosphoinositides.” 2006. Doctoral Dissertation, Vanderbilt University. Accessed January 19, 2021.
http://hdl.handle.net/1803/10502.
MLA Handbook (7th Edition):
Henage, Lee Gardner. “Kinetic analysis of phospholipase D: Allosteric modulation by monomeric GTPases, protein kinase C, and polyphosphoinositides.” 2006. Web. 19 Jan 2021.
Vancouver:
Henage LG. Kinetic analysis of phospholipase D: Allosteric modulation by monomeric GTPases, protein kinase C, and polyphosphoinositides. [Internet] [Doctoral dissertation]. Vanderbilt University; 2006. [cited 2021 Jan 19].
Available from: http://hdl.handle.net/1803/10502.
Council of Science Editors:
Henage LG. Kinetic analysis of phospholipase D: Allosteric modulation by monomeric GTPases, protein kinase C, and polyphosphoinositides. [Doctoral Dissertation]. Vanderbilt University; 2006. Available from: http://hdl.handle.net/1803/10502
. 
Open Access Theses and Dissertations