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Nuclear movement relative to cell bodies is a fundamental process during certain aspects of mammalian retinal development. During the generation of photoreceptor cells in the cell division cycle, the nuclei of progenitors oscillate between the apical and basal surfaces of the neuroblastic layer (NBL). This process is termed interkinetic nuclear migration(More)
Hydroxyindole-O-methyltransferase (HIOMT, EC 2.1.1.4) catalyzes the methylation of acetylserotonin to complete the synthesis of melatonin in the pineal and retina. A complete 1728 nucleotide cDNA encoding rat pineal HIOMT was isolated, characterized, and used to evaluate day/night levels of HIOMT mRNA. As previously reported for HIOMT enzyme activity, HIOMT(More)
Desensitization plays an important role in the rapid termination of G-protein signaling pathways. This process, which involves phosphorylation by a G-protein-coupled receptor kinase (GRK) followed by arrestin binding, has been studied extensively in the rod photoreceptor cell of the mammalian retina. In contrast, less is known regarding desensitization in(More)
The retinoblastoma protein (Rb) regulates proliferation, cell fate specification and differentiation in the developing central nervous system (CNS), but the role of Rb in the developing mouse retina has not been studied, because Rb-deficient embryos die before the retinas are fully formed. We combined several genetic approaches to explore the role of Rb in(More)
Joubert syndrome related disorders (JSRDs) have broad but variable phenotypic overlap with other ciliopathies. The molecular etiology of this overlap is unclear but probably arises from disrupting common functional module components within primary cilia. To identify additional module elements associated with JSRDs, we performed homozygosity mapping followed(More)
High acuity, color vision in humans is initiated in cones by a receptor/G-protein-linked phototransduction cascade. G-protein-linked receptors are rapidly deactivated by receptor phosphorylation and the binding of a member of the "arrestin" family of proteins. Divergence in amino acid sequence at the carboxyl terminus of S-antigen (rod photoreceptor(More)
Nanosecond, megavolt-per-meter, pulsed electric fields induce phosphatidylserine (PS) externalization, intracellular calcium redistribution, and apoptosis in Jurkat T-lymphoblasts, without causing immediately apparent physical damage to the cells. Intracellular calcium mobilization occurs within milliseconds of pulse exposure, and membrane phospholipid(More)
Arrestins are proteins that arrest the activity of G protein-coupled receptors (GPCRs). While it is well established that normal inactivation of photoexcited rhodopsin, the GPCR of rod phototransduction, requires arrestin (Arr1), it has been controversial whether the same requirement holds for cone opsin inactivation. Mouse cone photoreceptors express two(More)
The retinas of mice null for the neural retina leucine zipper transcription factor (Nrl-/-) contain no rods but are populated instead with photoreceptors that on ultrastructural, histochemical, and molecular criteria appear cone like. To characterize these photoreceptors functionally, responses of single photoreceptors of Nrl-/- mice were recorded with(More)
Arylalkylamine N-acetyltransferase (AA-NAT, E. C. 2.3.1.87) is the enzyme that catalyzes the transfer of an acetyl group from acetyl-CoA to serotonin to form N-acetylserotonin (NAS) in the indoleamine biosynthetic pathway. Bovine pineal AA-NAT, partially purified on an anion exchange column, displayed an 8-fold higher enzymatic activity in pineals from(More)