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Hexameric architecture of CstF supported by CstF-50 homodimerization domain structure.

ABSTRACT: The Cleavage stimulation Factor (CstF) complex is composed of three subunits and is essential for pre-mRNA 3'-end processing. CstF recognizes U and G/U-rich cis-acting RNA sequence elements and helps stabilize the Cleavage and Polyadenylation Specificity Factor (CPSF) at the polyadenylation site as required for productive RNA cleavage. Here, we describe the crystal structure of the N-terminal domain of Drosophila CstF-50 subunit. It forms a compact homodimer that exposes two geometrically opposite, identical, and conserved surfaces that may serve as binding platform. Together with previous data on the structure of CstF-77, homodimerization of CstF-50 N-terminal domain supports the model in which the functional state of CstF is a heterohexamer.

SUBMITTER: Moreno-Morcillo M

PROVIDER: S-EPMC3039141 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Hexameric architecture of CstF supported by CstF-50 homodimerization domain structure.

Moreno-Morcillo María M Moreno-Morcillo María M Minvielle-Sébastia Lionel L Mackereth Cameron C Fribourg Sébastien S

RNA (New York, N.Y.) 20110113 3

The Cleavage stimulation Factor (CstF) complex is composed of three subunits and is essential for pre-mRNA 3'-end processing. CstF recognizes U and G/U-rich cis-acting RNA sequence elements and helps stabilize the Cleavage and Polyadenylation Specificity Factor (CPSF) at the polyadenylation site as required for productive RNA cleavage. Here, we describe the crystal structure of the N-terminal domain of Drosophila CstF-50 subunit. It forms a compact homodimer that exposes two geometrically opposi ...[more]

PMID: 21233223

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