Showing papers by "Jose C. Florez published in 1995"
TL;DR: The production and mapping of one of these mutations in the mouse should accelerate the elucidation of the molecular events involved in the generation of circadian rhythms in mammals.
Abstract: Circadian rhythms are a cardinal feature of living organisms. The stereotypical organization of homeostatic, endocrine and behavioural variables around the 24-hour cycle constitutes one of the most conserved attributes among species. It is now well established that circadian rhythmicity is not a learned behaviour, but is genetically transmitted and therefore subject to genetic manipulations. Recent advances in the circadian field have demonstrated that circadian oscillations are cell autonomous, that the circadian mechanism operates through a negative feedback loop and that a growing number of genes is under circadian control. Furthermore, single-gene mutations have been isolated in mammals that have profound effects on circadian behaviour. The production and mapping of one of these mutations in the mouse, an organism about which there exists a wealth of genetic information, should accelerate the elucidation of the molecular events involved in the generation of circadian rhythms in mammals.
27 citations
TL;DR: Using two-dimensional gel analysis, this work has identified a 30 kDa cytosolic protein (p30) whose radiolabeling was consistently increased in parallel with increases in arylalkylamine N- acetyltransferase activity and melatonin production that were induced by forskolin and/or camptothecin.
Abstract: The synthesis of melatonin in Xenopus retinas, chick and quail retinal cell cultures, and Y79 human retinoblastoma cells is stimulated by cAMP through a protein synthesis-dependent mechanism. In Y79 retinoblastoma cells, combined treatment with the RNA synthesis inhibitor camptothecin and agents that elevate cAMP, such as forskolin, causes a synergistic elevation of melatonin. Using two-dimensional gel analysis we have identified a 30 kDa cytosolic protein (p30) whose radiolabeling was consistently increased in parallel with increases in arylalkylamine N-acetyltransferase activity and melatonin production that were induced by forskolin and/or camptothecin. Pulse-chase experiments suggest that the elevation in radiolabeling of p30 is due to increased synthesis. Three candidate proteins found in the mammalian pineal, protein 14-3-3, malate dehydrogenase, and recoverin, do not comigrate with p30.
9 citations