Two isoforms of chicken melanopsins show blue light sensitivity.
Melanopsin is a vertebrate non-visual opsin and functions as a circadian photoreceptor in mammalian retinas. Here we found the expression of two kinds of melanopsin genes in the chicken pineal gland and identified the presence of five isoforms derived from these two genes. Reconstitution of the recombinant proteins with 11-cis-retinal revealed that at least two of these melanopsin protein isoforms can function as blue-sensitive photopigments with absorption maxima at 476-484nm. These values are consistent with maximal sensitivities of action spectra determined from the physiological and behavioral studies on mammalian melanopsins. The melanopsin isoforms found in this study may function as pineal circadian photoreceptors.
Torii
Masaki
M
Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Kojima
Daisuke
D
Okano
Toshiyuki
T
Nakamura
Atsushi
A
Terakita
Akihisa
A
Shichida
Yoshinori
Y
Wada
Akimori
A
Fukada
Yoshitaka
Y
D000818:Animals; D001483:Base Sequence; D002645:Chickens / Q000235:genetics* / Q000378:metabolism*; D002940:Circadian Rhythm; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D015870:Gene Expression; D008297:Male; D018462:Photobiology; D020419:Photoreceptor Cells, Vertebrate / Q000378:metabolism / Q000528:radiation effects; D010802:Phylogeny; D010870:Pineal Gland / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D017299:Rod Opsins / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects*; D013053:Spectrophotometry; D000099210:Melanopsin
D017931:DNA Primers; D018076:DNA, Complementary; D020033:Protein Isoforms; D011994:Recombinant Proteins; D017299:Rod Opsins; D000099210:Melanopsin