FEATURES

FAMILY

DESCRIPTION

Also known as LARP1_HUMAN, LARP1, KIAA0731, LARP. RNA-binding protein that regulates the translation of specific target mRNA species downstream of the mTORC1 complex, in function of growth signals and nutrient availability (PubMed:20430826, PubMed:23711370, PubMed:24532714, PubMed:25940091, PubMed:28650797, PubMed:28673543, PubMed:29244122). Interacts on the one hand with the 3' poly-A tails that are present in all mRNA molecules, and on the other hand with the 7-methylguanosine cap structure of mRNAs containing a 5' terminal oligopyrimidine (5'TOP) motif, which is present in mRNAs encoding ribosomal proteins and several components of the translation machinery (PubMed:23711370, PubMed:25940091, PubMed:28650797, PubMed:29244122, PubMed:26206669, PubMed:28379136). The interaction with the 5' end of mRNAs containing a 5'TOP motif leads to translational repression by preventing the binding of EIF4G1 (PubMed:25940091, PubMed:28650797, PubMed:29244122, PubMed:28379136). When mTORC1 is activated, LARP1 is phosphorylated and dissociates from the 5' untranslated region (UTR) of mRNA (PubMed:25940091, PubMed:28650797). Does not prevent binding of EIF4G1 to mRNAs that lack a 5'TOP motif (PubMed:28379136). Interacts with the free 40S ribosome subunit and with ribosomes, both monosomes and polysomes (PubMed:20430826, PubMed:24532714, PubMed:25940091, PubMed:28673543). Under normal nutrient availability, interacts primarily with the 3' untranslated region (UTR) of mRNAs encoding ribosomal proteins and increases protein synthesis (PubMed:23711370, PubMed:28650797). Associates with actively translating ribosomes and stimulates translation of mRNAs containing a 5'TOP motif, thereby regulating protein synthesis, and as a consequence, cell growth and proliferation (PubMed:20430826, PubMed:24532714). Stabilizes mRNAs species with a 5'TOP motif, which is required to prevent apoptosis (PubMed:20430826, PubMed:23711370, PubMed:25940091, PubMed:28673543)., (Microbial infection) Positively regulates the replication of dengue virus (DENV). Interacts with PABPC1/PABP (PubMed:20430826, PubMed:24532714, PubMed:25940091, PubMed:23711370, PubMed:28650797). Interacts with EIF4A1 (PubMed:24532714). Interacts with RPTOR (PubMed:24532714, PubMed:25940091, PubMed:28650797). Recruited to the active mTORC1 complex via interaction with RPTOR (PubMed:25940091, PubMed:28650797). Inhibition of mTORC1 activity strongly reduces interaction with RPTOR and the mTORC1 complex (PubMed:25940091, PubMed:28650797). Identified in a complex with mRNA, PABPC1, EIF4E and EIF4G1 (PubMed:20430826, PubMed:28650797). Found in a complex with PABPC1 and SHFL (PubMed:26735137).

EXTERNAL LINKS

LARP1

La-related protein 1

LARP1

Molecular Synopsis