Progesterone receptor membrane component 1 facilitates Ca²⁺ signal amplification between endosomes and the endoplasmic reticulum.

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.

SUBMITTER: Gunaratne GS 

PROVIDER: S-EPMC10685313 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature