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Golgi anti-apoptotic proteins are highly conserved ion channels that affect apoptosis and cell migration.

ABSTRACT: Golgi anti-apoptotic proteins (GAAPs) are multitransmembrane proteins that are expressed in the Golgi apparatus and are able to homo-oligomerize. They are highly conserved throughout eukaryotes and are present in some prokaryotes and orthopoxviruses. Within eukaryotes, GAAPs regulate the Ca(2+) content of intracellular stores, inhibit apoptosis, and promote cell adhesion and migration. Data presented here demonstrate that purified viral GAAPs (vGAAPs) and human Bax inhibitor 1 form ion channels and that vGAAP from camelpox virus is selective for cations. Mutagenesis of vGAAP, including some residues conserved in the recently solved structure of a related bacterial protein, BsYetJ, altered the conductance (E207Q and D219N) and ion selectivity (E207Q) of the channel. Mutation of residue Glu-207 or -178 reduced the effects of GAAP on cell migration and adhesion without affecting protection from apoptosis. In contrast, mutation of Asp-219 abrogated the anti-apoptotic activity of GAAP but not its effects on cell migration and adhesion. These results demonstrate that GAAPs are ion channels and define residues that contribute to the ion-conducting pore and affect apoptosis, cell adhesion, and migration independently.

SUBMITTER: Carrara G

PROVIDER: S-EPMC4416878 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Golgi anti-apoptotic proteins are highly conserved ion channels that affect apoptosis and cell migration.

Carrara Guia G Saraiva Nuno N Parsons Maddy M Byrne Bernadette B Prole David L DL Taylor Colin W CW Smith Geoffrey L GL

The Journal of biological chemistry 20150224 18

Golgi anti-apoptotic proteins (GAAPs) are multitransmembrane proteins that are expressed in the Golgi apparatus and are able to homo-oligomerize. They are highly conserved throughout eukaryotes and are present in some prokaryotes and orthopoxviruses. Within eukaryotes, GAAPs regulate the Ca(2+) content of intracellular stores, inhibit apoptosis, and promote cell adhesion and migration. Data presented here demonstrate that purified viral GAAPs (vGAAPs) and human Bax inhibitor 1 form ion channels ...[more]

PMID: 25713081

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Golgi anti-apoptotic proteins are highly conserved ion channels that affect apoptosis and cell migration.

Publications

Golgi anti-apoptotic proteins are highly conserved ion channels that affect apoptosis and cell migration.

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