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Transpupillary Two-Photon In Vivo Imaging of the Mouse Retina
Published on: February 13, 2021
TTF-1 expression in PACAP-expressing retinal ganglion cells
Young June Son1, Jeong Woo Park, Byung Ju Lee
1Department of Biological Sciences, College of Natural Sciences, University of Ulsan, Ulsan 680-749, Korea.
Molecules and Cells
|April 28, 2007
Summary
Thyroid transcription factor 1 (TTF-1) is found in retinal ganglion cells (RGCs) that produce pituitary adenylate cyclase-activating polypeptide (PACAP). This suggests TTF-1 regulates PACAP expression in these specific RGCs, impacting the mammalian central clock.
Area of Science:
- Neuroscience
- Molecular Biology
- Chronobiology
Background:
- Mammalian circadian rhythms are regulated by the suprachiasmatic nucleus (SCN).
- Light input to the SCN triggers retinal ganglion cells (RGCs) to release pituitary adenylate cyclase-activating polypeptide (PACAP).
- Thyroid transcription factor 1 (TTF-1) was previously identified as a regulator of PACAP gene expression in the rat hypothalamus.
Purpose of the Study:
- To investigate the expression of TTF-1 in PACAP-synthesizing RGCs.
- To determine if TTF-1 is specifically localized within PACAP-producing RGCs.
Main Methods:
- Fluorescence in situ hybridization (FISH) was used to detect TTF-1 expression in retinal cells.
- Double FISH experiments were performed to co-localize TTF-1 and PACAP expression.
Main Results:
- TTF-1 was highly expressed in RGCs in the superior retina, with lower expression in the inferior retina.
- TTF-1 expression was exclusively found in RGCs that also produce PACAP.
Conclusions:
- TTF-1 is specifically expressed in PACAP-producing RGCs.
- These findings indicate a regulatory role for TTF-1 in PACAP-expressing RGCs.
- This implicates TTF-1 in the light-induced regulation of the mammalian central clock via PACAP signaling.
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