Mark W. Hankins

TL;DR: The rod–cone and melanopsin systems together seem to provide all of the photic input for these accessory visual functions such as pupillary light reflex and circadian photo-entrainment.

TL;DR: It is indicated that light signals for irradiance detection are dissociated from pattern vision at the retinal ganglion cell level, and animals that cannot detect light for NIF functions are still capable of image formation.

TL;DR: It is shown that heterologous expression of human melanopsin in a mouse paraneuronal cell line (Neuro-2a) is sufficient to render these cells photoreceptive and that melanopigment functions as a bistable pigment in this system, having an intrinsic photoisomerase regeneration function that is chromatically shifted to longer wavelengths.

TL;DR: The discovery of this remarkable new photoreceptor system is outlined, the structure of melanopsin is reviewed, and a working model of melanOPSin phototransduction is concluded.

TL;DR: This work addresses the deficit in individual contribution of each photoreceptor class to irradiance responses using mice expressing human red cone opsin, and reveals an unexpectedly important role for rods in retinal circuitry upstream of mRGCs.