Ascidian arrestin (Ci-arr), the origin of the visual and nonvisual arrestins of vertebrate.
Arrestin is one of the key proteins for the termination of G protein signaling. Activated G protein-coupled receptors (GPCRs) are specifically phosphorylated by G protein-coupled receptor kinases (GRKs) and then bind to arrestins to preclude the receptor/G protein interaction, resulting in quenching of the following signal transduction. Vertebrates possess two types of arrestin; visual arrestin expressed exclusively in photoreceptor cells in retinae and pineal organs, and beta-arrestin, which is expressed ubiquitously. Unlike visual arrestin, beta-arrestin contains the clathrin-binding domain at the C-terminus, responsible for the agonist-induced internalization of GPCRs. Here, we isolated a novel arrestin gene (Ci-arr) from the primitive chordate, the ascidian Ciona intestinalis larvae. The deduced amino acid sequence suggests that Ci-Arr be closely related to vertebrate arrestins. Interestingly, this arrestin has the feature of both visual and beta-arrestin. Whereas the expression of Ci-arr was restricted to the photoreceptors in the larvae similarly to visual arrestin, the gene product, containing the clathrin-binding domain, promoted the GPCR internalization in HEK293tsA201 cells similarly to beta-arrestin. The phylogenetic tree shows that Ci-Arr is branched from a common root of visual and beta-arrestins. Southern analysis suggests that the Ciona genome contains only one gene for the arrestin family. These results suggest that the visual and beta-arrestin genes were generated by the duplication of the prototypical arrestin gene like Ci-arr in the early evolution of vertebrates.
Nakagawa
Masashi
M
Department of Life Science, Graduate School of Science, Himeji Institute of Technology, Kamigori, Akoh-Gun, Hyogo, Japan. nakagawa@sci.himeji-tech.ac.jp
Orii
Hidefumi
H
Yoshida
Norihiro
N
Jojima
Eri
E
Horie
Takeo
T
Yoshida
Reiko
R
Haga
Tatsuya
T
Tsuda
Motoyuki
M
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D019393:Arrestin / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology; D019390:Arrestins / Q000235:genetics*; D002460:Cell Line; D003001:Cloning, Molecular; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D007668:Kidney / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D014561:Urochordata / Q000235:genetics*; D014714:Vertebrates
D000318:Adrenergic beta-Agonists; D019393:Arrestin; D019390:Arrestins; D018343:Receptors, Adrenergic, beta-2; D007545:Isoproterenol