Figure 10. Decreased SCN activation and increased vSPVZ activation by light in Rai1 haplo-insufficient mice.

(A) Illustration of anatomical delimitation (white dashed lines) of SCN and vSPVZ regions at bregma ~ −0.71 mm and ~ −0.83 mm used to count c-FOS-positive (c-FOS⁺) cells in B and C. SCN contour is readably visible by the marked density of cells within the SCN. DAPI staining in black labels cell nuclei. The vSPVZ contour was defined following published coordinates (Paxinos and Franklin, 2013). Note that top photo in A is identical to top-left photo in B with DAPI in blue on black background allowing visualization of c-FOS immunofluorescence in red in the ventral retinorecipient SCN core (B) Example of representative immunofluorescence staining of four sections (upper two panels at −0.71 mm, lower 2–0.83 mm) of two wild-type (left) and two Rai1^+/- heterozygous (right panels) mice. White horizontal bars in each photo of Panels A and B mark 100 μm. (C) A 1-hr-light pulse (LP) produced a smaller c-FOS immunoreactivity response in the SCN of Rai1^+/- mice compared to wild-type littermates. This is reflected by a reduced number of c-FOS-positive cells (left panel; **p<0.005; t-tests). In the vSPVZ, a 1-hr-light pulse produced a larger response in c-FOS immunoreactivity in Rai1+/- mice (right panel; *p<0.05; t-test; n = 6 and 7 in Rai1^+/- and Rai1^+/+ mice). Two control groups did not receive a light pulse (CTRL: n = 3/genotype). Note the different scaling for the SCN and vSPVZ panels. c-FOS immunoreactivity was averaged for the −0.71 and −0.83 mm sections within animals.

DOI: http://dx.doi.org/10.7554/eLife.23292.020