The primary structure of iodopsin, a chicken red-sensitive cone pigment.
A purified iodopsin was digested by CNBr or several proteolytic enzymes into fragments, the amino acid sequences of which were determined. A partial sequence of the C-terminal fragment was utilized for synthesizing an oligonucleotide probe which identified the iodopsin cDNA (1339 bases). The deduced amino acid sequence (362 residues) had 80%, 42%, or 43% homology to that of human red-sensitive cone pigment, cattle or chicken rhodospin, respectively. Although the hydropathy profile implies that iodopsin, like rhodopsin, has 7 transmembrane alpha-helical segments, iodopsin may have a hydrophilic pocket near the seventh segment on the basis of the unexpected cleavages in the middle of the segment VII by chymotrypsin under nondenaturing conditions.
Kuwata
O
O
Department of Biophysics, Faculty of Science, Kyoto University, Japan.
Imamoto
Y
Y
Okano
T
T
Kokame
K
K
Kojima
D
D
Matsumoto
H
H
Morodome
A
A
Fukada
Y
Y
Shichida
Y
Y
Yasuda
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002645:Chickens; D003488:Cyanogen Bromide; D004247:DNA; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes; D010446:Peptide Fragments / Q000737:chemistry; D011487:Protein Conformation; D012168:Retinal Pigments / Q000737:chemistry* / Q000235:genetics; D012243:Rhodopsin / Q000737:chemistry; D017299:Rod Opsins; D012689:Sequence Homology, Nucleic Acid
D015345:Oligonucleotide Probes; D010446:Peptide Fragments; D012168:Retinal Pigments; D017299:Rod Opsins; C034941:iodopsin; D004247:DNA; D012243:Rhodopsin; D003488:Cyanogen Bromide