| 2009 |
LARP6 binds the conserved 5' stem-loop (5'SL) in the 5'UTR of type I collagen mRNAs (COL1A1 and COL1A2) in a sequence-specific manner with Kd ~1.4 nM, using a bipartite RNA binding domain (La motif + RRM) that contacts two single-stranded regions of the stem-loop. In the cytoplasm, LARP6 does not associate with polysomes; overexpression blocks ribosomal loading on collagen mRNAs, while knockdown also decreases polysomal loading. LARP6 activity is required for focal synthesis of collagen polypeptides at discrete ER regions. |
Cloning and biochemical binding assays (Kd determination), siRNA knockdown, polysome fractionation, collagen-GFP reporter imaging |
Journal of molecular biology |
High |
19917293
|
| 2014 |
LARP6 requires synergy between its La motif (LaM) and RRM1, as well as the interdomain linker, for sequence-specific recognition of the collagen 5'SL RNA. Crystal/NMR structures of the LaM and RRM1 of human LARP6 revealed considerable structural variation from the prototypic La protein and an unprecedented fold for the RRM1; mutagenesis guided by the structures confirmed that neither domain alone is sufficient. |
X-ray crystallography/NMR structure determination, mutagenesis, RNA binding assays |
Nucleic acids research |
High |
25488812
|
| 2014 |
Five specific nucleotides within the single-stranded regions of the collagen 5'SL are critical for high-affinity LARP6 binding (mutation of individual nucleotides abolishes binding). T133 in the La domain is critical for protein folding, and loop 3 in the RRM is critical for 5'SL binding. Loop 3 also mediates interaction of LARP6 with the protein translocation channel SEC61; a LARP6 mutant that binds 5'SL but cannot interact with SEC61 acts as a dominant negative suppressor of collagen synthesis, indicating LARP6 targets collagen mRNAs to SEC61 translocons for coordinated translation. |
Gel mobility shift assay, mutagenesis, co-immunoprecipitation, dominant-negative overexpression |
RNA biology |
High |
25692237
|
| 2014 |
LARP6 associates with collagen mRNAs at the ER membrane independently of translation (collagen mRNAs remain ER-associated even when translation is inhibited). Knockdown of LARP6 or depolymerization of nonmuscle myosin filaments releases collagen mRNAs from the ER membrane and causes hypermodification, poor secretion, and cytosolic accumulation of collagen polypeptides, indicating LARP6 and nonmuscle myosin cooperate to partition collagen mRNAs to the ER membrane prior to signal peptide synthesis for coordinated translation initiation. |
Subcellular fractionation, siRNA knockdown, nonmuscle myosin depolymerization, pulse-chase secretion assay |
PloS one |
High |
25271881
|
| 2013 |
FKBP3 (FK506 binding protein 3, also called FKBP25) interacts with LARP6 and co-precipitates collagen mRNAs. FK506 (tacrolimus) weakens the FKBP3–LARP6 interaction and reduces pull-down of collagen mRNAs with FKBP3, leading to aberrant translation of collagen mRNAs and prevention of collagen synthesis and fibrosis in vivo. |
Co-immunoprecipitation, pull-down of RNA, in vivo fibrosis model |
PloS one |
Medium |
23755290
|
| 2016 |
LARP6 is phosphorylated at S451 by the PI3K/Akt pathway in lung fibroblasts, and this phosphorylation is a prerequisite for phosphorylation at other serines (hierarchical order). S451A dominant-negative mutant drastically reduces collagen secretion and induces hypermodification of collagen α2(I) polypeptides, establishing Akt-mediated phosphorylation of LARP6 as critical for regulating translation and folding of collagen polypeptides. |
Mass spectrometry phosphorylation mapping, PI3K/Akt pathway inhibitors, dominant-negative overexpression, pulse-chase secretion assay, mutagenesis |
Scientific reports |
High |
26932461
|
| 2017 |
mTORC1 phosphorylates LARP6 on S348 and S409. The S348A/S409A double mutant acts as a dominant negative in collagen biosynthesis, retards secretion, and causes excessive posttranslational modifications. mTORC1 phosphorylation of LARP6 promotes its interaction with the accessory protein STRAP (needed for coordinated translation of collagen mRNAs) and releases LARP6 from the ER membrane, enabling a new round of translation. |
mTORC1 inhibitor (rapamycin), raptor knockdown, dominant-negative overexpression, co-immunoprecipitation with STRAP, subcellular fractionation |
Scientific reports |
High |
28112218
|
| 2014 |
IGF-1 increases LARP6 expression and the level of COL1A1 and COL1A2 mRNA bound to LARP6 via PI3K/Akt/p70S6k signaling. Mutation of the 5'SL of Col1a1 mRNA (which inhibits LARP6 binding) or sequestration of LARP6 with a decoy RNA abolishes IGF-1-stimulated collagen type I synthesis, confirming that LARP6 binding to collagen mRNAs is essential for IGF-1's effect on collagen production. |
RNA immunoprecipitation (RIP) + qPCR, 5'SL mutation, RNA decoy sequestration, PI3K/Akt pathway inhibitors |
The Journal of biological chemistry |
High |
24469459
|
| 2021 |
The La domain of LARP6 alone is necessary and sufficient for sequence-specific recognition of the collagen 5'SL RNA. A three-amino-acid RNK motif in the flexible loop connecting the second α-helix to the β-sheet of the La domain is critical for binding; mutation of any of these three residues abolishes binding. The RRM increases stability of the La domain–5'SL complex but does not make extensive contacts with 5'SL. The RNK motif is absent from other LARPs that cannot bind 5'SL. |
Mutagenesis, UV-crosslinking mapping, RNA binding assays, domain-deletion analysis |
Journal of molecular biology |
High |
34896113
|
| 2021 |
CRTH2 (a prostaglandin D2 receptor), trafficked to the ER membrane in fibroblasts in a caveolin-1-dependent manner, binds the collagen mRNA recognition motif of LARP6 and promotes degradation of collagen mRNA. CRTH2 deficiency increases collagen biosynthesis and exacerbates fibrosis in mice, which is rescued by LARP6 depletion, placing CRTH2 as an upstream negative regulator of LARP6 function. |
Co-immunoprecipitation, caveolin-1-dependent trafficking assay, CRTH2 and LARP6 knockdown/knockout mouse models, epistasis |
The EMBO journal |
High |
34223653
|
| 2024 |
In Xenopus multiciliated cells (MCCs), LARP6 co-localizes with DNAAF6 in biomolecular condensates (dynein axonemal particles) and the two proteins synergize to control ciliogenesis. LARP6 binds tubulin alpha 1c-like mRNA encoding α-tubulin, a major ciliary axoneme component; a DNAAF6 mutant that cannot bind LARP6 fails to restore α-tubulin protein expression at the apical side of MCCs, demonstrating that the LARP6–DNAAF6 interaction in condensates regulates α-tubulin production during ciliogenesis. |
Co-localization in Xenopus embryo MCCs, co-immunoprecipitation, RNA binding assay, DNAAF6 morphant rescue with wild-type vs. binding-deficient mutant |
The Journal of biological chemistry |
Medium |
38762183
|
| 2025 |
An intrinsically disordered N-terminal IDR of LARP6 restricts conformational flexibility of the adjacent La-module and forms auxiliary contacts with RNA, thereby narrowing RNA-binding selectivity. Deletion of the N-terminal IDR broadens LARP6 RNA footprints (iCLIP). This IDR-mediated selectivity is required for LARP6-driven cancer cell viability and invasion, as shown by mutagenesis and cellular functional assays. |
Mass spectrometry-based RNA interaction mapping in living cells, iCLIP, mutagenesis, cancer cell invasion/viability assays |
Nature communications |
High |
41714637
|
| 2026 |
LARP6 is upregulated in activated hepatic stellate cells (HSCs) in MASH/MetALD by JUNB transcriptional activation. eCLIP-ribosome profiling integration shows LARP6 interacts with >300 mature mRNAs including structural elements in COL1A1, COL1A2, and COL3A1 to regulate their translation. IP-mass spectrometry identified LARP6 protein-protein interactions with mRNA translation components and the actin cytoskeleton. |
eCLIP, ribosome profiling, IP-mass spectrometry, snRNA-seq, ATAC-seq, HSC-specific siRNA knockdown |
The Journal of clinical investigation |
High |
41746718
|
| 2025 |
Solution NMR structure of the La domain of human LARP6 in the RNA-bound state reveals a non-canonical binding interface integrating electrostatic and hydrophobic contacts with shape complementarity for 5'SL recognition. Chemical shift perturbation, solvent paramagnetic relaxation enhancement, intermolecular NOEs, and targeted mutagenesis identify this interface; the La domain alone discriminates 5'SL from homopolymeric or purely helical hairpin RNAs with low-nanomolar affinity, overturning the view that the RRM is required for recognition. |
Solution NMR structure determination, chemical shift perturbation, solvent PRE, intermolecular NOEs, mutagenesis, RNA binding assays |
bioRxivpreprint |
Medium |
bio_10.1101_2025.05.22.652967
|
| 2023 |
LARP6 binds ZNF267 mRNA and regulates its stability and translation in colorectal cancer cells. Reduced ZNF267 by LARP6 inhibits downstream SGMS2 expression, causing ceramide/sphingomyelin imbalance and enhanced autophagy, thereby suppressing CRC progression. |
RIP-seq, RIP-qPCR, stable overexpression/knockdown, mRNA stability assay, autophagy assay |
Journal of experimental & clinical cancer research |
Medium |
36691044
|
| 2025 |
In MDA-MB-231 triple-negative breast cancer cells, LARP6 directly binds mRNAs (iRIP-seq identifies CGACGAG binding motif) and regulates alternative splicing of >1000 events, with regulated genes enriched in DNA repair and cell cycle pathways, promoting cancer cell proliferation and invasion. |
iRIP-seq, RNA-seq, RT-qPCR, RIP-qPCR |
Scientific reports |
Medium |
40050364
|