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The PML nuclear bodies-associated protein TTRAP regulates ribosome biogenesis in nucleolar cavities upon proteasome inhibition.

ABSTRACT: TRAF and TNF receptor-associated protein (TTRAP) is a multifunctional protein that can act in the nucleus as a 5'-tyrosyl DNA phosphodiesterase and in the cytoplasm as a regulator of cell signaling. In this paper we show that in response to proteasome inhibition TTRAP accumulates in nucleolar cavities in a promyelocytic leukemia protein-dependent manner. In the nucleolus, TTRAP contributes to control levels of ribosomal RNA precursor and processing intermediates, and this phenotype is independent from its 5'-tyrosyl DNA phosphodiesterase activity. Our findings suggest a previously unidentified function for TTRAP and nucleolar cavities in ribosome biogenesis under stress.

SUBMITTER: Vilotti S

PROVIDER: S-EPMC3278732 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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The PML nuclear bodies-associated protein TTRAP regulates ribosome biogenesis in nucleolar cavities upon proteasome inhibition.

Vilotti S S Biagioli M M Foti R R Dal Ferro M M Lavina Z Scotto ZS Collavin L L Del Sal G G Zucchelli S S Gustincich S S

Cell death and differentiation 20110916 3

TRAF and TNF receptor-associated protein (TTRAP) is a multifunctional protein that can act in the nucleus as a 5'-tyrosyl DNA phosphodiesterase and in the cytoplasm as a regulator of cell signaling. In this paper we show that in response to proteasome inhibition TTRAP accumulates in nucleolar cavities in a promyelocytic leukemia protein-dependent manner. In the nucleolus, TTRAP contributes to control levels of ribosomal RNA precursor and processing intermediates, and this phenotype is independen ...[more]

PMID: 21921940

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