paper results2

The authors first cloned melanopsin cDNA in rat cells to show that the protein sequence is nearly identical to that of mice. Then they generated specific antibodies targeting melanopsin to show the subset of cells that contained the protein. Tau-lacZ targeting shows the projections of melanopsin positive cells to the SCN and other regions of the brain. Lastly, they used a combination of immunofluorescence and Lucifer Yellow to show that intrinsically photosensitive RGC’s were melanopsin positive. Figure 3 shows that the authors targeted the tau-lacZ gene locus RGC’s and used immunofluorescence in mice. The structure of melanopsin positive cells was similar to that in rats. X-gal labeling not only showed retinal labeling of axons, cell bodies and dendrites, but it also showed B-galactosidase activity in parts of the brain such as the SCN, the olivary pretectal nucleus, the dorsal lateral geniculate, and other parts of the brain. This finding suggested that melanopsin positive cells are involved with processing information that is relayed to the brain.