Molecular Biology Commons^™

The Musashi Rna Binding Proteins Are Regulators Of Alternative Splicing And Protein Expression In Photoreceptor Cells, Fatimah Kh. Matalkah

Graduate Theses, Dissertations, and Problem Reports

The Musashi (Msi) family of RNA binding proteins consists of two paralogs, Msi1 and Msi2, that are highly conserved across species. The two paralogs have emerged as factors that promote stem cell proliferation by post-transcriptionally regulating translation. In addition to their expression in stem cells, the Musashi proteins are also expressed in postmitotic neurons, including the photoreceptor cells. The Musashi proteins have been observed to maintain high expression levels in the postmitotic photoreceptors within the eye of both invertebrates and vertebrates. These observations suggest an additional role in the maintenance of terminally differentiated neurons.

Building upon these observations, we investigated …

Photoreceptor Phosphodiesterase (Pde6): Structure, Regulatory Mechanisms, And Implications For Treatment Of Retinal Diseases, Rick H. Cote, Richa Gupta, Michael J. Irwin, Xin Wang

Faculty Publications

The photoreceptor phosphodiesterase (PDE6) is a member of large family of Class I phosphodiesterases responsible for hydrolyzing the second messengers cAMP and cGMP. PDE6 consists of two catalytic subunits and two inhibitory subunits that form a tetrameric protein. PDE6 is a peripheral membrane protein that is localized to the signaling-transducing compartment of rod and cone photoreceptors. As the central effector enzyme of the G-protein coupled visual transduction pathway, activation of PDE6 catalysis causes in a rapid decrease in cGMP levels that results in closure of cGMP-gated ion channels in the photoreceptor plasma membrane. Because of its importance in the phototransduction …

Photoreceptor Phosphodiesterase (Pde6): Activation And Inactivation Mechanisms During Visual Transduction In Rods And Cones, Rick H. Cote

Faculty Publications

Rod and cone photoreceptors of the vertebrate retina utilize cGMP as the primary

intracellular messenger for the visual signaling pathway that converts a light stimulus into an electrical response. cGMP metabolism in the signal-transducing photoreceptor outer segment reflects the balance of cGMP synthesis (catalyzed by guanylyl cyclase) and degradation (catalyzed by the photoreceptor phosphodiesterase, PDE6). Upon light stimulation, rapid activation of PDE6 by the heterotrimeric G-protein (transducin) triggers a dramatic drop in cGMP levels that lead to cell hyperpolarization. Following cessation of the light stimulus, the lifetime of activated PDE6 is also precisely regulated by additional processes. This review summarizes …