title: Expression of budding yeast FKBP12 confers rapamycin susceptibility to the unicellular red alga Cyanidioschyzon merolae.
abstract: The target of rapamycin (TOR) is serine/threonine protein kinase that is highly conserved among eukaryotes and can be inactivated by the antibiotic rapamycin through the formation of a ternary complex composed of rapamycin and two proteins, TOR and FKBP12. Differing from fungi and animals, plant FKBP12 proteins are unable to form the ternary complex, and thus plant TORs are insensitive to rapamycin. This has led to a poor understanding of TOR functions in plants. As a first step toward the understanding of TOR function in a rapamycin-insensitive unicellular red alga, Cyanidioschyzon merolae, we constructed a rapamycin-susceptible strain in which the Saccharomyces cerevisiae FKBP12 protein (ScFKBP12) was expressed. Treatment with rapamycin resulted in growth inhibition and decreased polysome formation in this strain. Binding of ScFKBP12 with C. merolae TOR in the presence of rapamycin was demonstrated in vivo and in vitro by pull-down experiments. Moreover, in vitro kinase assay showed that inhibition of C. merolae TOR kinase activity was dependent on ScFKBP12 and rapamycin.
authors: Chemical Resources Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama 332-0012, Japan.
authors: Sousuke
authors: S
authors: Imamura
authors: Aiko
authors: A
authors: Ishiwata
authors: Satoru
authors: S
authors: Watanabe
authors: Hirofumi
authors: H
authors: Yoshikawa
authors: Kan
authors: K
authors: Tanaka
mesh_terms: D020418:Algal Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology*; D003001:Cloning, Molecular; D004352:Drug Resistance, Microbial; D015870:Gene Expression; D000461:Rhodophyta / Q000166:cytology / Q000187:drug effects* / Q000235:genetics* / Q000254:growth & development; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D020123:Sirolimus / Q000494:pharmacology*; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D022061:Tacrolimus Binding Protein 1A / Q000235:genetics*
chemical_list: D020418:Algal Proteins; D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D029701:Saccharomyces cerevisiae Proteins; D058570:TOR Serine-Threonine Kinases; D022061:Tacrolimus Binding Protein 1A; D020123:Sirolimus
keywords: Cyanidioschyzon merolae; DMSO; FKBP12; His-tag; Rapamycin; Red alga; TOR kinase; dimethyl sulfoxide; histidine-tag; kDa; kilodalton