Figure 6. PER-T610A/S613A displays prolonged expression in the small LN_vs.

Brains from male per⁰¹ flies expressing the indicated transgene were stained with anti-PER (green; UP1140) and anti-PDF (blue; HH74). Small ventral lateral neurons (LN_vs) are shown in each panel. ZT time points are indicated at the top of each set of panels. (A–F, O–R) Wild type PER (per13.2) accumulates in the nucleus of small LN_vs starting at approximately ZT22, is highly expressed and nuclear by ZT0, and is largely absent by ZT8. (I–N, S–V) PER-T610A/S613A exhibits prolonged expression during the day, ZT2-14, and is turned-over at ∼ZT14, much later than wild type PER. Additionally, the double mutant protein appears to accumulate slightly slower than wild type (compare time points at ZT22 and ZT24) (W) Diagram depicting the highest levels of PER-13.2 (dark blue) and PER-T610A/S613A (dark green) throughout the day.