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

Medical Anatomy Commons

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

Articles 1 - 3 of 3

Full-Text Articles in Medical Anatomy

Control Of Mitochondrial Motility And Distribution By The Calcium Signal: A Homeostatic Circuit., Muqing Yi, David Weaver, György Hajnóczky Nov 2004

Control Of Mitochondrial Motility And Distribution By The Calcium Signal: A Homeostatic Circuit., Muqing Yi, David Weaver, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitochondria are dynamic organelles in cells. The control of mitochondrial motility by signaling mechanisms and the significance of rapid changes in motility remains elusive. In cardiac myoblasts, mitochondria were observed close to the microtubular array and displayed both short- and long-range movements along microtubules. By clamping cytoplasmic [Ca2+] ([Ca2+]c) at various levels, mitochondrial motility was found to be regulated by Ca2+ in the physiological range. Maximal movement was obtained at resting [Ca2+]c with complete arrest at 1-2 microM. Movement was fully recovered by returning to resting [Ca2+]c, and inhibition could be repeated with no apparent desensitization. The inositol 1,4,5-trisphosphate- or …


Signaling Switches And Bistability Arising From Multisite Phosphorylation In Protein Kinase Cascades., Nick I Markevich, Jan B. Hoek, Boris N. Kholodenko Feb 2004

Signaling Switches And Bistability Arising From Multisite Phosphorylation In Protein Kinase Cascades., Nick I Markevich, Jan B. Hoek, Boris N. Kholodenko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitogen-activated protein kinase (MAPK) cascades can operate as bistable switches residing in either of two different stable states. MAPK cascades are often embedded in positive feedback loops, which are considered to be a prerequisite for bistable behavior. Here we demonstrate that in the absence of any imposed feedback regulation, bistability and hysteresis can arise solely from a distributive kinetic mechanism of the two-site MAPK phosphorylation and dephosphorylation. Importantly, the reported kinetic properties of the kinase (MEK) and phosphatase (MKP3) of extracellular signal-regulated kinase (ERK) fulfill the essential requirements for generating a bistable switch at a single MAPK cascade level. Likewise, …


Creation Of Non-Human Primate Neurogenetic Disease Models By Gene Targeting And Nuclear Transfer, Robert B. Norgren Jan 2004

Creation Of Non-Human Primate Neurogenetic Disease Models By Gene Targeting And Nuclear Transfer, Robert B. Norgren

Journal Articles: Genetics, Cell Biology & Anatomy

Genetically modified rhesus macaques are necessary because mouse models are not suitable for a number of important neurogenetic disorders; for example, Kallmann's syndrome, Lesch-Nyhan's disease and Ataxia-Telangiectasia. Mouse models may not be suitable because there may be no mouse ortholog of the human gene of interest, as is the case for Kallmann's syndrome, or because mutant mice do not exhibit the same phenotype observed in humans, as is the the case for Lesch-Nyhan's disease and Ataxia-Telangiectasia. Non-human primate models of neurogenetic diseases are expected to more closely resemble human diseases than existing mouse models. Genetically modified rhesus macaques can be …