Isolation and characterization of melanopsin (Opn4) from the Australian marsupial Sminthopsis crassicaudata (fat-tailed dunnart).

ABSTRACT: Melanopsin confers photosensitivity to a subset of retinal ganglion cells and is responsible for many non-image-forming tasks, like the detection of light for circadian entrainment. Recently, two melanopsin genes, Opn4m and Opn4x, were described in non-mammalian vertebrates. However, only one form, Opn4m, has been described in the mammals, although studies to date have been limited to the placentals and have not included the marsupials. We report here the isolation and characterization of an Opn4 gene from an Australian marsupial, the fat-tailed dunnart (Sminthopsis crassicaudata), and present evidence which suggests that the Opn4x gene was lost before the placental/marsupial split. In situ hybridization shows that the expression of Opn4 in the dunnart eye is restricted to a subset of gang

SUBMITTER: Pires SS 

PROVIDER: S-EPMC3227130 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature