Assessment of endocytic traffic and Ocrl function in the developing zebrafish neuroepithelium

OCRL1 Deficiency Affects the Intracellular Traffic of ApoER2 and Impairs Reelin-Induced Responses

Lowe Syndrome (LS) is a rare X-linked disorder characterized by renal dysfunction, cataracts, and several central nervous system (CNS) anomalies. The mechanisms underlying the neurological dysfunction in LS remain unclear, albeit they share some phenotypic characteristics similar to the deficiency or dysfunction of the Reelin signaling, a relevant pathway with roles in CNS development and neuronal functions. In this study, we investigated the role of OCRL1, an inositol polyphosphate 5-phosphatase encoded by the OCRL gene, mutated in LS, focusing on its impact on endosomal trafficking and receptor recycling in human neuronal cells. Specifically, we tested the effects of OCRL1 deficiency in the trafficking and signaling of ApoER2/LRP8, a receptor for the ligand Reelin. We found that loss of OCRL1 impairs ApoER2 intracellular trafficking, leading to reduced receptor expression and decreased levels at the plasma membrane. Additionally, human neurons deficient in OCRL1 showed impairments in ApoER2/Reelin-induced responses. Our findings highlight the critical role of OCRL1 in regulating ApoER2 endosomal recycling and its impact on the ApoER2/Reelin signaling pathway, providing insights into potential mechanisms underlying the neurological manifestations of LS.

First person – Daniel Williams

First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping researchers promote themselves alongside their papers. Daniel Williams is first author on ‘ Assessment of endocytic traffic and Ocrl function in the developing zebrafish neuroepithelium’, published in JCS. Daniel conducted the research described in this article while a PhD Student in Professor Martin Lowe's lab at the School of Biosciences, Faculty of Biology, Medicine and Health, University of Manchester, UK. He then did a postdoc with Professor David Brough, University of Manchester, UK, investigating the regulation of the NLRP3 inflammasome. Daniel is now a postdoctoral research associate in the lab of Andrew Peden at the School of Biosciences, University of Sheffield, UK, studying the regulation of membrane contact site formation between endosomes and the endoplasmic reticulum.