Purpose: Arrestin is expressed in the retinal photoreceptor cells and pinealocytes. We investigated whether it is also expressed in any other tissues in adult mice. Methods: We constructed a fusion gene which has well characterized a mouse or a bovine arrestin promoter and a Lac-Z reporter gene. Three lines of transgenic mice having a fusion gene were generated. The expression of β-Gal as well arrestin, phosducin, and opsin was studied with color reaction and immunostaining with antibody probes. Results: In addition to the photoreceptor cells and pinealocytes, β-GAL was expressed at high levels in very small number of well defined cell types in the areas of habenula commissura, amygdala, and superior colliculus of those transgenic animals. Immunocytochemistry with antibody probes indicated that arrestin and phosducin were expressed at high levels and opsin was expressed at very low levels. The pattern of expression of these proteins is similar to that of pinealocytes and not that of retinal photoreceptor cells. Conclusion: We found new cell types in brain which express arrestin, phosducin, and opsin. If these cells secrete melatonin, it is highly probable that diurnal cycle of the brain cells is controlled by melatonin secreted from those cells. In contrast, melatonin in peripheral blood from pinealocytes regulates the cycle in the rest of the body.
|Journal||Investigative Ophthalmology and Visual Science|
|Publication status||Published - 1996 Feb 15|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience