Affinage

RILPL1

RILP-like protein 1 · UniProt Q5EBL4

Length
403 aa
Mass
47.1 kDa
Annotated
2026-04-28
15 papers in source corpus 12 papers cited in narrative 11 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

RILPL1 is a phospho-Rab effector protein that functions as a critical downstream mediator of LRRK2 kinase signaling at centrosomes and lysosomes, linking Parkinson's disease-associated kinase hyperactivation to defects in ciliogenesis, centrosome cohesion, and lysosomal positioning. At the mother centriole, LRRK2-phosphorylated RAB8A and RAB10 recruit RILPL1 to subdistal appendages, where the phospho-Rab/RILPL1 complex displaces CDK5RAP2 to disrupt centrosome cohesion and blocks CP110 uncapping by preventing TTBK2 recruitment, thereby inhibiting primary ciliogenesis (PMID:31428781, PMID:33653948, PMID:35776681, PMID:35721463). At lysosomes, LRRK2-phosphorylated RAB12 recruits RILPL1 to bind the integral membrane protein TMEM55B via a defined TBM motif and to couple with dynein–dynactin through p150Glued, driving perinuclear lysosomal clustering and opposing JIP4-mediated kinesin-dependent tubule extension on damaged lysosomes (PMID:37086089, PMID:38091401, PMID:40990465, PMID:41314214). CGG repeat expansion in the RILPL1 5′ UTR causes oculopharyngodistal myopathy type 4 (OPDM4), with both toxic polyglycine protein aggregates and RNA foci contributing to pathogenesis (PMID:35148830).

Mechanistic history

Synthesis pass · year-by-year structured walk · 9 steps
  1. 2012 High

    Establishing that RILPL1 localizes to the mother centriole and primary cilium and functions in ciliary membrane protein homeostasis resolved where the protein acts and provided the first cellular phenotype for its depletion.

    Evidence Live-cell microscopy, siRNA depletion, 3D culture assays in epithelial cells

    PMID:23264467

    Open questions at the time
    • Upstream regulators of RILPL1 centriolar localization unknown
    • Mechanism of protein removal from ciliary membrane not defined
    • Whether RILPL1 and RILPL2 have distinct versus redundant roles at cilia unclear
  2. 2019 High

    Demonstrating that LRRK2-phosphorylated RAB8A and RAB10 are recruited to centrosomal RILPL1, causing centrosome cohesion deficits and ciliogenesis defects, established RILPL1 as the key effector linking pathogenic LRRK2 signaling to centrosomal dysfunction.

    Evidence Phospho-RAB antibodies, RNAi/KO, LRRK2 inhibitor treatment in patient-derived cells and LRRK2-mutant mouse astrocytes

    PMID:31428781

    Open questions at the time
    • Precise molecular mechanism of centrosome cohesion loss not identified
    • Whether ciliogenesis block is direct or secondary to cohesion defects unclear
  3. 2021 High

    Ordering the ciliogenesis block mechanistically — phospho-Rab10/RILPL1 prevents TTBK2 recruitment and CP110 uncapping at the mother centriole — defined RILPL1's position in the early ciliogenesis pathway and explained how it blocks cilium initiation rather than maintenance.

    Evidence Live-cell imaging, Rab10 KO and RILPL1 KO rescue, R1441C LRRK2 knock-in MEFs

    PMID:33653948

    Open questions at the time
    • How RILPL1 physically occludes TTBK2 binding not resolved
    • Whether other centriolar capping factors are affected unknown
  4. 2022 High

    Identifying CDK5RAP2 displacement as the specific mechanism of RILPL1-mediated centrosome cohesion loss distinguished this from linker-protein disruption models and pinpointed the downstream target at the centrosome.

    Evidence Co-IP, immunofluorescence, siRNA, patient iPSC-derived models

    PMID:35721463 PMID:35776681

    Open questions at the time
    • Whether RILPL1 competes directly with CDK5RAP2 for a binding site or acts indirectly not distinguished
    • Structural basis of the interaction unknown
  5. 2022 Medium

    Discovering that CGG repeat expansion in the RILPL1 5′ UTR causes oculopharyngodistal myopathy type 4 linked a repeat expansion disease to the RILPL1 locus, with evidence for dual toxicity from polyglycine protein inclusions and RNA foci.

    Evidence Long-read WGS, RP-PCR, immunofluorescence, and muscle biopsy in OPDM4 families identified by two independent groups

    PMID:35148830 PMID:35700120

    Open questions at the time
    • No functional mutagenesis of the RILPL1 protein itself in this disease context
    • Whether expansion affects endogenous RILPL1 protein expression or function not tested
    • Animal model for OPDM4 not established
  6. 2023 High

    Establishing a Rab12–RILPL1 axis at lysosomes expanded the RILPL1 effector repertoire beyond centrosomal Rab8/10 and demonstrated that LRRK2-phosphorylated Rab12 recruits RILPL1 to drive perinuclear lysosomal clustering.

    Evidence RAB12 KO and RILPL1 KO, phospho-mimetic/dead Rab12 mutants, Co-IP, immunofluorescence

    PMID:37086089

    Open questions at the time
    • Motor protein mechanism driving clustering not identified at this point
    • Physiological consequence of perinuclear clustering unclear
  7. 2023 High

    Identifying TMEM55B as the lysosomal receptor for RILPL1 and showing that VPS35[D620N] drives LRRK2-dependent lysosomal RILPL1 recruitment (with subsequent proteasomal degradation reducing RILPL1 levels) connected the Parkinson's-linked retromer pathway to RILPL1-dependent lysosomal regulation.

    Evidence Lysosomal proteomics, Co-IP, RILPL1-TMEM55B interface mutagenesis, KO mice, LRRK2/proteasome inhibitor rescue

    PMID:38091401

    Open questions at the time
    • Structural basis of the RILPL1–TMEM55B interaction not yet resolved at atomic level
    • Functional consequence of RILPL1 proteasomal degradation on lysosomal dynamics in vivo not fully characterized
  8. 2024 High

    Revealing that RILPL1 binds p150Glued to engage dynein–dynactin and opposes JIP4-driven kinesin-mediated tubule extension on damaged lysosomes defined the motor-coupling mechanism by which RILPL1 controls lysosomal positioning and tubulation.

    Evidence Lysosomal proteomics, Co-IP of RILPL1–p150Glued, live imaging of LYTL tubule dynamics, KO cells, LLOMe damage model

    PMID:40990465

    Open questions at the time
    • Whether RILPL1–dynein coupling is direct or requires additional adaptors not established
    • Relative contributions of Rab10 vs Rab12 in lysosomal RILPL1 recruitment not dissected
  9. 2025 High

    Solving the crystal structure of the TMEM55B–RILPL1 TBM complex at atomic resolution defined the binding interface as backbone hydrogen bonding across tandem RING-like Zn²⁺-stabilized β-sandwich domains, anchored by two conserved glutamate residues, and revealed that the same TMEM55B groove binds multiple effectors (JIP3, JIP4, OCRL, WDR81, TBC1D9B).

    Evidence X-ray crystallography of TMEM55B alone and in complex with RILPL1 TBM, mutagenesis, Co-IP/MS

    PMID:41314214

    Open questions at the time
    • Structure of full-length RILPL1 and its simultaneous engagement of Rab and TMEM55B not determined
    • Competition dynamics between RILPL1 and other TBM-containing effectors on lysosomes not characterized in vivo

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key unresolved questions include the structural basis of full-length RILPL1 simultaneously engaging phospho-Rab proteins, TMEM55B, and dynactin; the physiological significance of RILPL1's lysosomal functions in neurodegeneration in vivo; and how RILPL1 loss affects ciliogenesis and lysosomal dynamics in dopaminergic neurons specifically relevant to Parkinson's disease.
  • No full-length RILPL1 structure available
  • No in vivo Parkinson's disease model with RILPL1 manipulation in dopaminergic neurons
  • Relationship between centrosomal and lysosomal RILPL1 pools not characterized

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0060090 molecular adaptor activity 5 GO:0008092 cytoskeletal protein binding 1
Localization
GO:0005815 microtubule organizing center 5 GO:0005764 lysosome 3 GO:0005929 cilium 1
Pathway
R-HSA-1852241 Organelle biogenesis and maintenance 6 R-HSA-162582 Signal Transduction 3 R-HSA-9609507 Protein localization 2 R-HSA-9612973 Autophagy 2

Evidence

Reading pass · 11 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2012 RILPL1 localizes specifically to the distal end of the mother centriole and to the primary cilium. Depletion of RILPL1 (and RILPL2) causes accumulation of signaling proteins in the ciliary membrane and prevents proper epithelial cell organization in 3D culture, indicating RILPL1 regulates ciliary membrane protein concentration by promoting protein removal from the primary cilium. Live-cell microscopy, siRNA depletion, immunofluorescence, 3D culture assays Molecular biology of the cell High 23264467
2019 LRRK2-phosphorylated RAB8A and RAB10 are recruited to centrosome-localized RILPL1, causing centrosomal cohesion deficits in dividing cells and ciliogenesis defects. Both phenotypes depend on RAB8, RAB10, and RILPL1, and are reversed by LRRK2 kinase inhibition. Immunofluorescence, phospho-RAB antibodies, RNAi/KO, patient-derived peripheral cells, primary astrocytes from mutant LRRK2 mice, LRRK2 inhibitor treatment Human molecular genetics High 31428781
2021 LRRK2-phosphorylated Rab10 recruits RILPL1 to the mother centriole, where the phospho-Rab10/RILPL1 complex blocks CP110 uncapping by preventing TTBK2 recruitment, thereby inhibiting early ciliogenesis. RILPL1 overexpression alone recapitulates the CP110 retention phenotype. Live-cell fluorescence microscopy, genetic knockouts (Rab10 KO, RILPL1 KO), LRRK2 kinase inhibition, MEF cells from R1441C LRRK2 knock-in mice Proceedings of the National Academy of Sciences of the United States of America High 33653948
2022 RILPL1 localizes to the subdistal appendage of the mother centriole and mediates centrosomal accumulation of LRRK2-phosphorylated Rab10 (and Rab8), causing centrosome cohesion deficits and impairing cell polarization. The cohesion defects are specific to RILPL1 (not RILPL2) and require the GTP conformation and phosphorylation status of the Rab proteins. Immunofluorescence, scratch wound assays, transfection of dominant-active/inactive Rab mutants, LRRK2 kinase inhibition, siRNA knockdown Biology open High 35776681
2022 Pathogenic LRRK2-mediated centrosomal cohesion deficits require RILPL1 and phospho-Rab proteins; mechanistically, the phospho-Rab/RILPL1 complex causes centrosomal displacement of CDK5RAP2, a protein critical for centrosome cohesion, without disrupting proteinaceous linker proteins. Co-immunoprecipitation, immunofluorescence, siRNA knockdown, iPS cell-derived models, transfected cell lines iScience High 35721463
2023 LRRK2-phosphorylated Rab12 (at Ser106) binds RILPL1 with enhanced affinity, recruiting it to lysosomes and causing perinuclear lysosomal clustering. Knockout of RAB12 or RILPL1 abolishes the perinuclear clustering, demonstrating a Rab12-RILPL1 axis controlling lysosomal transport. RAB12 KO cells, RILPL1 KO, re-expression of phospho-mimetic/phospho-dead Rab12 mutants, immunofluorescence, Co-IP FASEB journal High 37086089
2023 The Parkinson's VPS35[D620N] mutation drives LRRK2-mediated lysosomal recruitment of phospho-Rabs, which recruit RILPL1 to the lysosomal surface where it binds the lysosomal integral membrane protein TMEM55B via conserved regions. VPS35[D620N] reduces RILPL1 protein levels via proteasomal degradation (reversed by LRRK2 inhibition and proteasome inhibitors), and RILPL1 knockout enhances phospho-Rab substrate levels. Lysosomal proteomics, Co-IP, mutagenesis of RILPL1-TMEM55B interface, knockout mouse models (brain, lung, fibroblasts), LRRK2 inhibitor and proteasome inhibitor treatment Science advances High 38091401
2025 Crystal structures of TMEM55B cytosolic domain (residues 80–166) alone and in complex with a C-terminal RILPL1 peptide (TMEM55B-binding motif, TBM) reveal that the RILPL1 TBM binds a shallow groove across two tandem RING-like Zn2+-stabilized β-sandwich domains of TMEM55B via backbone hydrogen bonding anchored by two glutamate residues. TMEM55B also independently forms complexes (via conserved TBM) with JIP3, JIP4, OCRL, WDR81, and TBC1D9B. X-ray crystallography, Co-immunoprecipitation, mass spectrometry, mutagenesis Structure (London, England : 1993) High 41314214
2024 RILPL1 is recruited to LRRK2-positive damaged lysosomes via phospho-Rab proteins and promotes retraction of lysosomal tubulation/sorting (LYTL) tubules by binding to p150Glued (a dynactin subunit), facilitating dynein-dependent transport of lysosomes and tubules toward the minus-end of microtubules, opposing JIP4-driven kinesin-mediated tubule extension. Lysosomal proteomics (LRRK2 kinase inhibition), live-cell fluorescence microscopy, Co-IP (RILPL1–p150Glued), overexpression, KO cells, LLOMe lysosomal damage model The Journal of cell biology High 40990465
2024 RAB12 cooperates with LRRK2 to inhibit primary ciliogenesis and regulate centrosome homeostasis in astrocytes by enhancing Rab10 phosphorylation and recruiting RILPL1; deletion of Rab12 in astrocytes prevents the ciliary and centrosomal deficits caused by LRRK2-G2019S. Cryo-EM structure of RAB12-LRRK2 complex, phosphoproteomics, astrocyte-specific Rab12 KO, immunofluorescence bioRxiv (preprint)preprint Medium bio_10.1101_2024.07.17.603999
2022 CGG repeat expansion in the 5′ UTR of RILPL1 causes oculopharyngodistal myopathy type 4 (OPDM4). The expanded repeat is translated into a toxic poly-glycine protein that co-localizes with p62 in intranuclear inclusions, and expanded repeat RNA also forms toxic RNA foci, suggesting dual protein and RNA gain-of-function mechanisms. Long-read whole-genome sequencing, RP-PCR, AL-PCR, methylation analysis, immunofluorescence, muscle biopsy American journal of human genetics Medium 35148830 35700120

Source papers

Stage 0 corpus · 15 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2019 RAB8, RAB10 and RILPL1 contribute to both LRRK2 kinase-mediated centrosomal cohesion and ciliogenesis deficits. Human molecular genetics 73 31428781
2021 Pathogenic LRRK2 regulates ciliation probability upstream of tau tubulin kinase 2 via Rab10 and RILPL1 proteins. Proceedings of the National Academy of Sciences of the United States of America 66 33653948
2022 The CGG repeat expansion in RILPL1 is associated with oculopharyngodistal myopathy type 4. American journal of human genetics 58 35148830
2012 The Rilp-like proteins Rilpl1 and Rilpl2 regulate ciliary membrane content. Molecular biology of the cell 51 23264467
2023 Parkinson's VPS35[D620N] mutation induces LRRK2-mediated lysosomal association of RILPL1 and TMEM55B. Science advances 30 38091401
2022 GGC Repeat Expansion of RILPL1 is Associated with Oculopharyngodistal Myopathy. Annals of neurology 28 35700120
2022 Pathogenic LRRK2 regulates centrosome cohesion via Rab10/RILPL1-mediated CDK5RAP2 displacement. iScience 18 35721463
2022 The LRRK2 signaling network converges on a centriolar phospho-Rab10/RILPL1 complex to cause deficits in centrosome cohesion and cell polarization. Biology open 18 35776681
2023 Pathogenic LRRK2 compromises the subcellular distribution of lysosomes in a Rab12-RILPL1-dependent manner. FASEB journal : official publication of the Federation of American Societies for Experimental Biology 14 37086089
2024 Opposing actions of JIP4 and RILPL1 provide antagonistic motor force to dynamically regulate membrane reformation during lysosomal tubulation/sorting driven by LRRK2. bioRxiv : the preprint server for biology 5 38903076
2023 A large pedigree study confirmed the CGG repeat expansion of RILPL1 Is associated with oculopharyngodistal myopathy. BMC medical genomics 5 37864208
2025 Structural basis for binding of RILPL1 to TMEM55B reveals a lysosomal platform for adaptor assembly through a conserved peptide motif. Structure (London, England : 1993) 2 41314214
2025 A case report of oculopharyngodistal myopathy with 126 CGG repeat expansions in RILPL1. Frontiers in genetics 0 40084170
2025 Structural basis for binding of RILPL1 to TMEM55B reveals a lysosomal platform for adaptor assembly through a conserved TBM motif. bioRxiv : the preprint server for biology 0 40894729
2025 JIP4 and RILPL1 utilize opposing motor force to dynamically regulate lysosomal tubulation. The Journal of cell biology 0 40990465