TY - JOUR
T1 - La-related protein 1 (LARP1) represses terminal oligopyrimidine (TOP) mRNA translation downstream of mTOR complex 1 (mTORC1)
AU - Fonseca, Bruno D.
AU - Zakaria, Chadi
AU - Jia, Jian Jun
AU - Graber, Tyson E.
AU - Svitkin, Yuri
AU - Tahmasebi, Soroush
AU - Healy, Danielle
AU - Hoang, Huy Dung
AU - Jensen, Jacob M.
AU - Diao, Ilo T.
AU - Lussier, Alexandre
AU - Dajadian, Christopher
AU - Padmanabhan, Niranjan
AU - Wang, Walter
AU - Matta-Camacho, Edna
AU - Hearnden, Jaclyn
AU - Smith, Ewan M.
AU - Tsukumo, Yoshinori
AU - Yanagiya, Akiko
AU - Morita, Masahiro
AU - Petroulakis, Emmanuel
AU - González, Jose L.
AU - Hernández, Greco
AU - Alain, Tommy
AU - Damgaard, Christian K.
N1 - Publisher Copyright:
© 2015 by The American Society for Biochemistry and Molecular Biology, Inc. Published in the U.S.A.
PY - 2015/6/26
Y1 - 2015/6/26
N2 - The mammalian target of rapamycin complex 1 (mTORC1) is a critical regulator of protein synthesis. The best studied targets of mTORC1 in translation are the eukaryotic initiation factorbinding protein 1 (4E-BP1) and ribosomal protein S6 kinase 1 (S6K1). In this study, we identify the La-related protein 1 (LARP1) as a key novel target of mTORC1 with a fundamental role in terminal oligopyrimidine (TOP) mRNA translation. Recent genome-wide studies indicate that TOP and TOP-like mRNAs compose a large portion of the mTORC1 translatome, but the mechanism by which mTORC1 controls TOP mRNA translation is incompletely understood. Here, we report that LARP1 functions as a key repressor of TOP mRNA translation downstream of mTORC1. Our data show the following: (i) LARP1associates with mTORC1 via RAPTOR;(ii)LARP1 interacts with TOP mRNAs in an mTORC1-dependent manner; (iii) LARP1 binds the 5'TOP motif to repress TOP mRNA translation; and (iv) LARP1 competes with the eukaryotic initiation factor (eIF) 4G for TOP mRNA binding. Importantly, from a drug resistance standpoint, our data also show that reducing LARP1 protein levels by RNA interference attenuates the inhibitory effect of rapamycin, Torin1, and amino acid deprivation on TOP mRNA translation. Collectively, our findings demonstrate that LARP1 functions as an important repressor of TOP mRNA translation downstream of mTORC1.
AB - The mammalian target of rapamycin complex 1 (mTORC1) is a critical regulator of protein synthesis. The best studied targets of mTORC1 in translation are the eukaryotic initiation factorbinding protein 1 (4E-BP1) and ribosomal protein S6 kinase 1 (S6K1). In this study, we identify the La-related protein 1 (LARP1) as a key novel target of mTORC1 with a fundamental role in terminal oligopyrimidine (TOP) mRNA translation. Recent genome-wide studies indicate that TOP and TOP-like mRNAs compose a large portion of the mTORC1 translatome, but the mechanism by which mTORC1 controls TOP mRNA translation is incompletely understood. Here, we report that LARP1 functions as a key repressor of TOP mRNA translation downstream of mTORC1. Our data show the following: (i) LARP1associates with mTORC1 via RAPTOR;(ii)LARP1 interacts with TOP mRNAs in an mTORC1-dependent manner; (iii) LARP1 binds the 5'TOP motif to repress TOP mRNA translation; and (iv) LARP1 competes with the eukaryotic initiation factor (eIF) 4G for TOP mRNA binding. Importantly, from a drug resistance standpoint, our data also show that reducing LARP1 protein levels by RNA interference attenuates the inhibitory effect of rapamycin, Torin1, and amino acid deprivation on TOP mRNA translation. Collectively, our findings demonstrate that LARP1 functions as an important repressor of TOP mRNA translation downstream of mTORC1.
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U2 - 10.1074/jbc.M114.621730
DO - 10.1074/jbc.M114.621730
M3 - Article
C2 - 25940091
AN - SCOPUS:84941313390
VL - 290
SP - 15996
EP - 16020
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 26
ER -