Early Appearance of Nonvisual and Circadian Markers in the Developing Inner Retinal Cells of Chicken
Figure 4
Analysis of mRNA expression in primary cultures of chicken RGCs at E8 (a) and of HCs at E15 (b) and in the whole postnatal chicken retina. (a) Chicken embryonic retinas were dissected out at E8 and RGCs were purified and cultured. Expression of clock genes cryptochrome 1 (Cry 1), Clock, Bmal1, NPAS2, and Per 2 and clock-outputs: the melatonin synthesizing enzyme, arylalkylamine N-acetyltransferase (AA-NAT) mRNA was assessed by the reverse transcription- (RT-) polymerase chain reaction (PCR). Cry 1, Per2 Clock, Bmal1, and AA-NAT PCR products were found in RGC cultures whereas no detectable amplification was found for the NPAS2 transcript. (b) Chicken embryonic retinas were dissected out at E15, and HCs were purified and cultured. mRNA expression for clock genes cryptochromes 1 (Cry 1) and 2 (Cry 2), Bmal 1, and Clock and for the clock-outputs AA-NAT was assessed by RT-PCR from HCs at E15 (phase 2.5%) and samples from the whole postnatal retina (positive control). Positive amplification was found for the mRNAs of Cry 1, Per2, Bmal1, and AANAT whereas Cry2, NPAS2, and Clock amplifications products were not found in HC cultures.
