Progesterone receptor membrane component 1 facilitates Ca2+ signal amplification between endosomes and the endoplasmic reticulum.
J Biol Chem
; 299(12): 105378, 2023 Dec.
Article
em En
| MEDLINE
| ID: mdl-37866635
ABSTRACT
Membrane contact sites (MCSs) between endosomes and the endoplasmic reticulum (ER) are thought to act as specialized trigger zones for Ca2+ signaling, where local Ca2+ released via endolysosomal ion channels is amplified by ER Ca2+-sensitive Ca2+ channels into global Ca2+ signals. Such amplification is integral to the action of the second messenger, nicotinic acid adenine dinucleotide phosphate (NAADP). However, functional regulators of inter-organellar Ca2+ crosstalk between endosomes and the ER remain poorly defined. Here, we identify progesterone receptor membrane component 1 (PGRMC1), an ER transmembrane protein that undergoes a unique heme-dependent dimerization, as an interactor of the endosomal two pore channel, TPC1. NAADP-dependent Ca2+ signals were potentiated by PGRMC1 overexpression through enhanced functional coupling between endosomal and ER Ca2+ stores and inhibited upon PGRMC1 knockdown. Point mutants in PGMRC1 or pharmacological manipulations that reduced its interaction with TPC1 were without effect. PGRMC1 therefore serves as a TPC1 interactor that regulates ER-endosomal coupling with functional implications for cellular Ca2+ dynamics and potentially the distribution of heme.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Endossomos
/
Receptores de Progesterona
/
Sinalização do Cálcio
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Retículo Endoplasmático
Limite:
Humans
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article