Human La-related Protein 1, LARP1 ELI

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).