4 research outputs found
ACBD5 and VAPB mediate membrane associations between peroxisomes and the ER
Peroxisomes (POs) and the endoplasmic reticulum (ER) cooperate in cellular lipid metabolism and form tight structural associations, which were first observed in ultrastructural studies decades ago. PO–ER associations have been suggested to impact on a diverse number of physiological processes, including lipid metabolism, phospholipid exchange, metabolite transport, signaling, and PO biogenesis. Despite their fundamental importance to cell metabolism, the mechanisms by which regions of the ER become tethered to POs are unknown, in particular in mammalian cells. Here, we identify the PO membrane protein acyl-coenzyme A–binding domain protein 5 (ACBD5) as a binding partner for the resident ER protein vesicle-associated membrane protein-associated protein B (VAPB). We show that ACBD5–VAPB interaction regulates PO–ER associations. Moreover, we demonstrate that loss of PO–ER association perturbs PO membrane expansion and increases PO movement. Our findings reveal the first molecular mechanism for establishing PO–ER associations in mammalian cells and report a new function for ACBD5 in PO–ER tethering
ACBD5 and VAPB mediate membrane associations between peroxisomes and the ER
This is the final version of the article. Available from the publisher via the DOI in this record.Peroxisomes (POs) and the endoplasmic reticulum (ER) cooperate in cellular lipid metabolism and form tight structural
associations, which were first observed in ultrastructural studies decades ago. PO–ER associations have been suggested
to impact on a diverse number of physiological processes, including lipid metabolism, phospholipid exchange, metabolite
transport, signaling, and PO biogenesis. Despite their fundamental importance to cell metabolism, the mechanisms
by which regions of the ER become tethered to POs are unknown, in particular in mammalian cells. Here, we identify
the PO membrane protein acyl-coenzyme A–binding domain protein 5 (ACBD5) as a binding partner for the resident
ER protein vesicle-associated membrane protein-associated protein B (VAPB). We show that ACBD5–VAPB interaction
regulates PO–ER associations. Moreover, we demonstrate that loss of PO–ER association perturbs PO membrane expansion
and increases PO movement. Our findings reveal the first molecular mechanism for establishing PO–ER associations
in mammalian cells and report a new function for ACBD5 in PO–ER tethering.This work was supported by grants from the Biotechnology and Biological
Sciences Research Council (BB/K006231/1 and BB/
N01541X/1 to M. Schrader). J. Metz and M. Schrader are supported
by a Wellcome Trust Institutional Strategic Support Award
(WT097835MF and WT105618MA) and L.F. Godinho by a fellowship
from Fundação para a Ciência e a Tecnologia, Portugal (SFRH/
BPD/90084/2012). M. Schrader and A.S. Azadi are supported by
Marie Curie Initial Training Network action PerFuMe (316723).
M. Islinger is supported by MEAMEDMA Anschubförderung, Medical
Faculty Mannheim, University of Heidelberg