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Scotin, a novel p53-inducible proapoptotic protein located in the ER and the nuclear membrane.

ABSTRACT: p53 is a transcription factor that induces growth arrest or apoptosis in response to cellular stress. To identify new p53-inducible proapoptotic genes, we compared, by differential display, the expression of genes in spleen or thymus of normal and p53 nullizygote mice after gamma-irradiation of whole animals. We report the identification and characterization of human and mouse Scotin homologues, a novel gene directly transactivated by p53. The Scotin protein is localized to the ER and the nuclear membrane. Scotin can induce apoptosis in a caspase-dependent manner. Inhibition of endogenous Scotin expression increases resistance to p53-dependent apoptosis induced by DNA damage, suggesting that Scotin plays a role in p53-dependent apoptosis. The discovery of Scotin brings to light a role of the ER in p53-dependent apoptosis.

SUBMITTER: Bourdon JC

PROVIDER: S-EPMC2173124 | biostudies-literature | 2002 Jul

REPOSITORIES: biostudies-literature

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Scotin, a novel p53-inducible proapoptotic protein located in the ER and the nuclear membrane.

Bourdon J-C JC Renzing J J Robertson P L PL Fernandes K N KN Lane D P DP

The Journal of cell biology 20020722 2

p53 is a transcription factor that induces growth arrest or apoptosis in response to cellular stress. To identify new p53-inducible proapoptotic genes, we compared, by differential display, the expression of genes in spleen or thymus of normal and p53 nullizygote mice after gamma-irradiation of whole animals. We report the identification and characterization of human and mouse Scotin homologues, a novel gene directly transactivated by p53. The Scotin protein is localized to the ER and the nuclea ...[more]

PMID: 12135983

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