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Vaccinia virus N1L protein resembles a B cell lymphoma-2 (Bcl-2) family protein.

ABSTRACT: Poxviruses encode immuno-modulatory proteins capable of subverting host defenses. The poxvirus vaccinia expresses a small 14-kDa protein, N1L, that is critical for virulence. We report the crystal structure of N1L, which reveals an unexpected but striking resemblance to host apoptotic regulators of the B cell lymphoma-2 (Bcl-2) family. Although N1L lacks detectable Bcl-2 homology (BH) motifs at the sequence level, we show that N1L binds with high affinity to the BH3 peptides of pro-apoptotic Bcl-2 family proteins in vitro, consistent with a role for N1L in modulating host antiviral defenses.

SUBMITTER: Aoyagi M

PROVIDER: S-EPMC2222835 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature

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Vaccinia virus N1L protein resembles a B cell lymphoma-2 (Bcl-2) family protein.

Aoyagi Mika M Zhai Dayong D Jin Chaofang C Aleshin Alexander E AE Stec Boguslaw B Reed John C JC Liddington Robert C RC

Protein science : a publication of the Protein Society 20061122 1

Poxviruses encode immuno-modulatory proteins capable of subverting host defenses. The poxvirus vaccinia expresses a small 14-kDa protein, N1L, that is critical for virulence. We report the crystal structure of N1L, which reveals an unexpected but striking resemblance to host apoptotic regulators of the B cell lymphoma-2 (Bcl-2) family. Although N1L lacks detectable Bcl-2 homology (BH) motifs at the sequence level, we show that N1L binds with high affinity to the BH3 peptides of pro-apoptotic Bcl ...[more]

PMID: 17123957

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