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Essential requirement for JPT2 in NAADP-evoked Ca2+ signaling.

ABSTRACT: Nicotinic acid adenine dinucleotide phosphate (NAADP) is a second messenger that releases Ca2+ from acidic organelles through the activation of two-pore channels (TPCs) to regulate endolysosomal trafficking events. NAADP action is mediated by NAADP-binding protein(s) of unknown identity that confer NAADP sensitivity to TPCs. Here, we used a "clickable" NAADP-based photoprobe to isolate human NAADP-binding proteins and identified Jupiter microtubule-associated homolog 2 (JPT2) as a TPC accessory protein required for endogenous NAADP-evoked Ca2+ signaling. JPT2 was also required for the translocation of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus through the endolysosomal system. Thus, JPT2 is a component of the NAADP receptor complex that is essential for TPC-dependent Ca2+ signaling and control of coronaviral entry.

SUBMITTER: Gunaratne GS

PROVIDER: S-EPMC8315109 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Essential requirement for JPT2 in NAADP-evoked Ca2+ signaling.

Gunaratne Gihan S GS Brailoiu Eugen E He Shijun S Unterwald Ellen M EM Patel Sandip S Slama James T JT Walseth Timothy F TF Marchant Jonathan S JS

Science signaling 20210323 675

Nicotinic acid adenine dinucleotide phosphate (NAADP) is a second messenger that releases Ca2+ from acidic organelles through the activation of two-pore channels (TPCs) to regulate endolysosomal trafficking events. NAADP action is mediated by NAADP-binding protein(s) of unknown identity that confer NAADP sensitivity to TPCs. Here, we used a "clickable" NAADP-based photoprobe to isolate human NAADP-binding proteins and identified Jupiter microtubule-associated homolog 2 (JPT2) as a TPC ...[more]

PMID: 33758061

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