Medicine and Health Sciences Commons^™

Dysregulation Of Kv3.4 Channels In Dorsal Root Ganglia Following Spinal Cord Injury., David Ritter, Benjamin M Zemel, Tamara J Hala, Michael E O'Leary, Angelo C Lepore, Manuel Covarrubias

Farber Institute for Neuroscience Faculty Papers

Spinal cord injury (SCI) patients develop chronic pain involving poorly understood central and peripheral mechanisms. Because dysregulation of the voltage-gated Kv3.4 channel has been implicated in the hyperexcitable state of dorsal root ganglion (DRG) neurons following direct injury of sensory nerves, we asked whether such a dysregulation also plays a role in SCI. Kv3.4 channels are expressed in DRG neurons, where they help regulate action potential (AP) repolarization in a manner that depends on the modulation of inactivation by protein kinase C (PKC)-dependent phosphorylation of the channel's inactivation domain. Here, we report that, 2 weeks after cervical hemicontusion SCI, injured …

Egr-1 Induces Darpp-32 Expression In Striatal Medium Spiny Neurons Via A Conserved Intragenic Element., Serene Keilani, Samira Chandwani, Georgia Dolios, Alexey Bogush, Heike Beck, Antonis K Hatzopoulos, Gadiparthi N Rao, Elizabeth A Thomas, Rong Wang, Michelle E Ehrlich

Farber Institute for Neuroscience Faculty Papers

DARPP-32 (dopamine and adenosine 3', 5'-cyclic monophosphate cAMP-regulated phosphoprotein, 32 kDa) is a striatal-enriched protein that mediates signaling by dopamine and other first messengers in the medium spiny neurons. The transcriptional mechanisms that regulate striatal DARPP-32 expression remain enigmatic and are a subject of much interest in the efforts to induce a striatal phenotype in stem cells. We report the identification and characterization of a conserved region, also known as H10, in intron IV of the gene that codes for DARPP-32 (Ppp1r1b). This DNA sequence forms multiunit complexes with nuclear proteins from adult and embryonic striata of mice and rats. …

Characterization Of The Drosophila Slowpoke Binding Protein (Slob) Promoter, Amanda L. Sheldon, Lauren Manderfield, Irwin B. Levitan

Farber Institute for Neuroscience Faculty Papers

Drosophila SLOWPOKE (SLO) is a voltage and calcium dependent, large conductance potassium channel important for action potential repolarization, neuronal excitability, neurotransmitter release, and hormone secretion. SLO binding protein (SLOB) binds to and modulates SLO activity. We have shown previously that modulation of SLO by SLOB has profound effects on SLO channel currents, synaptic transmisison, and metabolism. Multiple isoforms of SLOB exist and are encoded by multiple transcripts; the isoforms are named based on their predicted protein molecular weights, in kilodaltons. In the Drosophila brain, SLOB57/51 proteins are expressed especially prominently in insulin producing neurons of the pars intercerebralis, while SLOB71/65 …

Dopaminergic Neurons Derived From Human Induced Pluripotent Stem Cells Survive And Integrate Into 6-Ohda-Lesioned Rats., Jingli Cai, Ming Yang, Elizabeth Poremsky, Sarah Kidd, Jay S Schneider, Lorraine Iacovitti

Farber Institute for Neuroscience Faculty Papers

Cell replacement therapy could be an important treatment strategy for Parkinson's disease (PD), which is caused by the degeneration of dopamine neurons in the midbrain (mDA). The success of this approach greatly relies on the discovery of an abundant source of cells capable of mDAergic function in the brain. With the paucity of available human fetal tissue, efforts have increasingly focused on renewable stem cells. Human induced pluripotent stem (hiPS) cells offer great promise in this regard. If hiPS cells can be differentiated into authentic mDA neuron, hiPS could provide a potential autologous source of transplant tissue when generated from …

Human Amniotic Fluid Stem Cells Do Not Differentiate Into Dopamine Neurons In Vitro Or After Transplantation In Vivo., Angela E Donaldson, Jingli Cai, Ming Yang, Lorraine Iacovitti

Farber Institute for Neuroscience Faculty Papers

Although embryonic stem (ES) cells can generate dopamine (DA) neurons that are potentially useful as a cell replacement therapy in Parkinson's disease (PD), associated ethical and practical concerns remain major stumbling blocks to their eventual use in humans. In this study, we examined human amniotic fluid stem (hAFS) cells derived from routine amniocenteses for their potential to give rise to DA neurons in vitro and following transplantation into the 6-hydroxydopamine-lesioned rat brain. We show that undifferentiated hAFS cells constitutively expressed mRNAs and proteins typical of stem cells but also cell derivatives of all three germ layers, including neural progenitors/neurons (nestin, …

Gene Expression Profile Of Neuronal Progenitor Cells Derived From Hescs: Activation Of Chromosome 11p15.5 And Comparison To Human Dopaminergic Neurons., William J Freed, Jia Chen, Cristina M Bäckman, Catherine M Schwartz, Tandis Vazin, Jingli Cai, Charles E Spivak, Carl R Lupica, Mahendra S Rao, Xianmin Zeng

Farber Institute for Neuroscience Faculty Papers

BACKGROUND: We initiated differentiation of human embryonic stem cells (hESCs) into dopamine neurons, obtained a purified population of neuronal precursor cells by cell sorting, and determined patterns of gene transcription.

METHODOLOGY: Dopaminergic differentiation of hESCs was initiated by culturing hESCs with a feeder layer of PA6 cells. Differentiating cells were then sorted to obtain a pure population of PSA-NCAM-expressing neuronal precursors, which were then analyzed for gene expression using Massive Parallel Signature Sequencing (MPSS). Individual genes as well as regions of the genome which were activated were determined.

PRINCIPAL FINDINGS: A number of genes known to be involved in the …

Evidence Against Roles For Phorbol Binding Protein Munc13-1, Adam Adaptor Eve-1, Or Vesicle Trafficking Phosphoproteins Munc18 Or Nsf As Phospho-State-Sensitive Modulators Of Phorbol/Pkc-Activated Alzheimer App Ectodomain Shedding., Annat F Ikin, Mirsada Causevic, Steve Pedrini, Lyndsey S Benson, Joseph D Buxbaum, Toshiharu Suzuki, Simon Lovestone, Shigeki Higashiyama, Tomas Mustelin, Robert D Burgoyne, Sam Gandy

Farber Institute for Neuroscience Faculty Papers

ABSTRACT: BACKGROUND: Shedding of the Alzheimer amyloid precursor protein (APP) ectodomain can be accelerated by phorbol esters, compounds that act via protein kinase C (PKC) or through unconventional phorbol-binding proteins such as Munc13-1. We have previously demonstrated that application of phorbol esters or purified PKC potentiates budding of APP-bearing secretory vesicles at the trans-Golgi network (TGN) and toward the plasma membrane where APP becomes a substrate for enzymes responsible for shedding, known collectively as alpha-secretase(s). However, molecular identification of the presumptive "phospho-state-sensitive modulators of ectodomain shedding" (PMES) responsible for regulated shedding has been challenging. Here, we examined the effects on …

Similar Promotion Of Abeta1-42 Fibrillogenesis By Native Apolipoprotein E Epsilon3 And Epsilon4 Isoforms., David Sweeney, Ralph Martins, Harry Levine, Jonathan D Smith, Sam Gandy

Farber Institute for Neuroscience Faculty Papers

The apolipoprotein E epsilon4 allele contributes to the genetic susceptibility underlying a large proportion (~40-60%) of typical, sporadic Alzheimer disease. Apolipoprotein E deficient mice made transgenic for human apolipoprotein E epsilon4 accumulate excess cerebral amyloid when compared to similarly prepared mice expressing human apolipoprotein E epsilon3. Therefore, it is important to search for relevant interactions(s) between apolipoprotein E epsilon4 and Abeta in order to clarify the biological role for apolipoprotein E epsilon4 in Alzheimer disease. Using a thioflavine T (ThT)-based assay, we have investigated the effects of native human apolipoprotein E isoforms on the kinetics of Abeta fibrillogenesis. No obvious …