Rilpl1, without commonly known aliases from the provided references, is a gene involved in multiple biological processes. It functions as a phospho-Rab effector protein, playing a role in the recruitment of proteins to the lysosome. It is associated with pathways related to lysosomal function, as well as cellular processes like ciliogenesis and centrosome cohesion [1,3,4]. Its biological importance extends to the context of diseases such as Parkinson's disease and oculopharyngodistal myopathy (OPDM), highlighting its significance in both neurodegenerative and neuromuscular disease research. Genetic models, such as knockout (KO) mouse models, can be valuable for studying Rilpl1's functions in vivo.

In mouse fibroblasts, brain, and lung, the Parkinson's-related VPS35[D620N] mutation reduces RILPL1 levels, and this reduction can be reversed by LRRK2 inhibition and proteasome inhibitors. Knockout of Rilpl1 in mouse models enhances phosphorylation of Rab substrates, demonstrating its role in regulating Rab protein phosphorylation in the context of Parkinson's-related pathways [1]. In the context of OPDM, GGC repeat expansions in the promoter region of Rilpl1 have been identified as a novel genetic cause in some Chinese Han families, designated as OPDM type 4. However, analysis of muscle samples showed no significant differences in RILPL1 mRNA or protein levels between OPDM patients and controls [2].

In conclusion, Rilpl1 has essential functions in regulating lysosomal protein recruitment, Rab protein phosphorylation, and is associated with centrosome cohesion and ciliogenesis. Through KO mouse models, its role in Parkinson's-related pathways has been revealed. In the area of OPDM, although Rilpl1's GGC repeat expansions are associated with the disease, the exact mechanism remains to be further explored. The study of Rilpl1 using genetic models contributes to understanding the pathogenesis of these diseases and may provide potential targets for treatment.

References:

1. Pal, Prosenjit, Taylor, Matthew, Lam, Pui Yiu, Pfeffer, Suzanne R, Alessi, Dario R. 2023. Parkinson's VPS35[D620N] mutation induces LRRK2-mediated lysosomal association of RILPL1 and TMEM55B. In Science advances, 9, eadj1205. doi:10.1126/sciadv.adj1205. https://pubmed.ncbi.nlm.nih.gov/38091401/

2. Zeng, Yi-Heng, Yang, Kang, Du, Gan-Qin, Wang, Zhi-Qiang, Wang, Ning. 2022. GGC Repeat Expansion of RILPL1 is Associated with Oculopharyngodistal Myopathy. In Annals of neurology, 92, 512-526. doi:10.1002/ana.26436. https://pubmed.ncbi.nlm.nih.gov/35700120/

3. Fdez, Elena, Madero-Pérez, Jesús, Lara Ordóñez, Antonio J, Wade-Martins, Richard, Hilfiker, Sabine. 2022. Pathogenic LRRK2 regulates centrosome cohesion via Rab10/RILPL1-mediated CDK5RAP2 displacement. In iScience, 25, 104476. doi:10.1016/j.isci.2022.104476. https://pubmed.ncbi.nlm.nih.gov/35721463/

4. Lara Ordónez, Antonio Jesús, Fernández, Belén, Fdez, Elena, Civiero, Laura, Hilfiker, Sabine. . RAB8, RAB10 and RILPL1 contribute to both LRRK2 kinase-mediated centrosomal cohesion and ciliogenesis deficits. In Human molecular genetics, 28, 3552-3568. doi:10.1093/hmg/ddz201. https://pubmed.ncbi.nlm.nih.gov/31428781/