RRC ID 12690
著者 Sato K, Yamashita T, Ohuchi H, Shichida Y.
タイトル Vertebrate ancient-long opsin has molecular properties intermediate between those of vertebrate and invertebrate visual pigments.
ジャーナル Biochemistry
Abstract VA/VAL opsin is one of the four kinds of nonvisual opsins that are closely related to vertebrate visual pigments in the phylogenetic tree of opsins. Previous studies indicated that among these opsins, parapinopsin and pinopsin exhibit molecular properties similar to those of invertebrate bistable visual pigments and vertebrate visual pigments, respectively. Here we show that VA/VAL opsin exhibits molecular properties intermediate between those of parapinopsin and pinopsin. VAL opsin from Xenopus tropicalis was expressed in cultured cells, and the pigment with an absorption maximum at 501 nm was reconstituted by incubation with 11-cis-retinal. Light irradiation of this pigment caused cis-to-trans isomerization of the chromophore to form a state having an absorption maximum in the visible region. This state has the ability to activate Gi and Gt types of G proteins. Therefore, the active state of VAL opsin is a visible light-absorbing intermediate, which probably has a protonated retinylidene Schiff base as its chromophore, like the active state of parapinopsin. However, this state was apparently photoinsensitive and did not show reverse reaction to the original pigment, unlike the active state of parapinopsin, and instead similar to that of pinopsin. Furthermore, the Gi activation efficiency of VAL opsin was between those of pinopsin and parapinopsin. Thus, the molecular properties of VA/VAL opsin give insights into the mechanism of conversion of the molecular properties from invertebrate to vertebrate visual pigments.
巻・号 50(48)
ページ 10484-90
公開日 2011-12-6
DOI 10.1021/bi201212z
PMID 22066464
MeSH Animals Cells, Cultured GTP-Binding Proteins / metabolism HEK293 Cells Humans Retinaldehyde / chemistry Retinaldehyde / radiation effects Rod Opsins / chemistry* Rod Opsins / radiation effects Xenopus* Xenopus Proteins / chemistry* Xenopus Proteins / radiation effects
IF 2.865
引用数 19
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
ツメガエル・イモリ X. tropicalis