title: The endoplasmic reticulum-localized protein TBL2 interacts with the 60S ribosomal subunit.
abstract: Transducin (beta)-like 2 (TBL2) is a poorly characterized protein comprising the N-terminal transmembrane region and the C-terminal WD40 domain. We previously showed that TBL2 is an endoplasmic reticulum (ER)-localized protein that interacts with PKR-like ER-resident kinase (PERK), and under ER stress, it mediates protein expression of activating transcription factor 4 (ATF4). However, further molecular characterization of TBL2 is useful to better understand the function of this molecule. Here, we show that TBL2 associates with the eukaryotic 60S ribosomal subunit but not with the 40S subunit. The association of TBL2 with the 60S subunit was ER stress independent while the TBL2-PERK interaction occurred upon ER stress. Immunoprecipitation analysis using TBL2 deletion mutants revealed that the WD40 domain was essential for the 60S subunit association. These results could provide an important clue to understanding how TBL2 is involved in the expression of specific proteins under ER stress conditions.
authors.affiliation: Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Tsukumo
authors.affiliation: Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan.
authors.forename: Satomi
authors.initials: S
authors.lastname: Tsukahara
authors.affiliation: Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan.
authors.forename: Aki
authors.initials: A
authors.lastname: Furuno
authors.affiliation: Biomedicinal Information Research Center, National Institute of Advanced Industrial Science and Technology, Koto-ku, Tokyo 135-0064, Japan.
authors.forename: Shun-ichiro
authors.initials: S
authors.lastname: Iemura
authors.affiliation: Biomedicinal Information Research Center, National Institute of Advanced Industrial Science and Technology, Koto-ku, Tokyo 135-0064, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Natsume
authors.affiliation: Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan. Electronic address: akihiro.tomida@jfcr.or.jp.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tomida
mesh_terms: D001665:Binding Sites; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D012270:Ribosomes / Q000378:metabolism*
chemical_list: C402405:TBL2 protein, human; D019204:GTP-Binding Proteins
keywords: 60S subunit; ER; Endoplasmic reticulum; PERK; Ribosome; TBL2