Evidence for indirect control of phospholipase C (PLC-beta) by retinoids in Drosophila phototransduction.
Mol Vis
; 7: 216-21, 2001 Sep 21.
Article
en En
| MEDLINE
| ID: mdl-11590363
ABSTRACT
PURPOSE:
To determine how retinoids regulate the phospholipase C (PLC) gene in the Drosophila visual system.METHODS:
Western blotting, activity analyses and immunocytochemistry were applied to Drosophila reared on various diets.RESULTS:
Western blots and activity analyses showed that retinoid deprivation decreases PLC, the product of the norpA gene, by approximately 1/3 to 1/2 in Drosophila. Immunocytochemistry using standard and confocal fluorescence microscopy confirmed the expectation that PLC is localized to the photoreceptive rhabdomeres. Rhabdomeres of flies that were retinoid deprived, or reared on other diets devoid of chromophore precursors, fluoresced brightly. These observations are consistent with earlier morphometric analyses showing that retinoid deprivation decreases the size of rhabdomeres. In a separate control, rhabdomeric PLC was shown to be virtually eliminated by retinoid deprivation in transgenic Drosophila where the norpA coding sequence was driven by the opsin promoter.CONCLUSIONS:
PLC is decreased by retinoid deprivation. Retinoid control of PLC is indirect, as expected, since the norpA promoter is so different from the promoter for rhodopsin's gene. PLC is not eliminated by deprivation but decreases in proportion to the associated decrease in rhabdomere size which, in turn, is caused by the opsin decrease. By contrast, opsin is controlled by retinoids both translationally by chromophore availability and transcriptionally. The fact that PLC is eliminated by retinoid deprivation when opsin's promoter drives the PLC gene is important evidence substantiating retinoid control via opsin's promoter.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Fosfolipasas de Tipo C
/
Retinoides
/
Visión Ocular
/
Deficiencia de Vitamina A
/
Células Fotorreceptoras de Invertebrados
/
Isoenzimas
Límite:
Animals
Idioma:
En
Revista:
Mol Vis
Asunto de la revista:
BIOLOGIA MOLECULAR
/
OFTALMOLOGIA
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos