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Trichoplein/mitostatin regulates endoplasmic reticulum-mitochondria juxtaposition.

ABSTRACT: Trichoplein/mitostatin (TpMs) is a keratin-binding protein that partly colocalizes with mitochondria and is often downregulated in epithelial cancers, but its function remains unclear. In this study, we report that TpMs regulates the tethering between mitochondria and endoplasmic reticulum (ER) in a Mitofusin 2 (Mfn2)-dependent manner. Subcellular fractionation and immunostaining show that TpMs is present at the interface between mitochondria and ER. The expression of TpMs leads to mitochondrial fragmentation and loosens tethering with ER, whereas its silencing has opposite effects. Functionally, the reduced tethering by TpMs inhibits apoptosis by Ca(2+)-dependent stimuli that require ER-mitochondria juxtaposition. Biochemical and genetic evidence support a model in which TpMs requires Mfn2 to modulate mitochondrial shape and tethering. Thus, TpMs is a new regulator of mitochondria-ER juxtaposition.

SUBMITTER: Cerqua C

PROVIDER: S-EPMC2966954 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Trichoplein/mitostatin regulates endoplasmic reticulum-mitochondria juxtaposition.

Cerqua Cristina C Anesti Vassiliki V Pyakurel Aswin A Liu Dan D Naon Deborah D Wiche Gerhard G Baffa Raffaele R Dimmer Kai S KS Scorrano Luca L

EMBO reports 20101008 11

Trichoplein/mitostatin (TpMs) is a keratin-binding protein that partly colocalizes with mitochondria and is often downregulated in epithelial cancers, but its function remains unclear. In this study, we report that TpMs regulates the tethering between mitochondria and endoplasmic reticulum (ER) in a Mitofusin 2 (Mfn2)-dependent manner. Subcellular fractionation and immunostaining show that TpMs is present at the interface between mitochondria and ER. The expression of TpMs leads to mitochondrial ...[more]

PMID: 20930847

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