Figure 4.

CRY expression in cry^b and cry deletion strains. Brains were dissected from cry deletion strains cry^ΔI2 and cry^ΔA2, cry^b mutant flies, and cry B2 (precise excision) flies collected at CT19 on the third day of DD, immunostained with CRY (GP23) and PER or PDF antisera, and imaged via confocal microscopy. A minimum of four cry^ΔI2, four cry^ΔA2, and six cry^b brains were analyzed with similar results. A. A 2μm z-stack projection through the left hemisphere of a cry^ΔI2 fly is shown. Colocalization of PER (green) and CRY (red) immunofluorescence is seen in the merged image as yellow. Arrows indicate PER and/or CRY immunostaining in oscillator neurons, which are labeled as in panel A of Fig. 3. B. A compressed stack of 6−8 1μm optical sections through the Pars Intercerebralus is shown. A merged image of CRY (green) and PER (red) immunofluorescence is shown. C. A compressed stack of 3−6 1μm optical sections through the lateral protocerebrum of cry B2 and cry^ΔA2 flies is shown. Colocalization of PDF (green) and CRY (red) immunofluorescence in s-LN_vs is seen in the merged image as yellow. D. A compressed stack of 3−4 2μm optical sections from the right brain hemispheres of cry^b flies is shown. Colocalization of CRY (green) and PER (red) immunofluorescence in the merged image is shown as yellow. Arrows indicate PER and/or CRY immunostaining in oscillator neurons, which are labeled as in panel A of Fig. 3.