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Structural and functional insights into the human Upf1 helicase core.

ABSTRACT: Nonsense-mediated mRNA decay (NMD) is an mRNA surveillance pathway that recognizes and degrades aberrant mRNAs containing premature stop codons. A critical protein in NMD is Upf1p, which belongs to the helicase super family 1 (SF1), and is thought to utilize the energy of ATP hydrolysis to promote transitions in the structure of RNA or RNA-protein complexes. The crystal structure of the catalytic core of human Upf1p determined in three states (phosphate-, AMPPNP- and ADP-bound forms) reveals an overall structure containing two RecA-like domains with two additional domains protruding from the N-terminal RecA-like domain. Structural comparison combined with mutational analysis identifies a likely single-stranded RNA (ssRNA)-binding channel, and a cycle of conformational change coupled to ATP binding and hydrolysis. These conformational changes alter the likely ssRNA-binding channel in a manner that can explain how ATP binding destabilizes ssRNA binding to Upf1p.

SUBMITTER: Cheng Z

PROVIDER: S-EPMC1782376 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature

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Structural and functional insights into the human Upf1 helicase core.

Cheng Zhihong Z Muhlrad Denise D Lim Meng Kiat MK Parker Roy R Song Haiwei H

The EMBO journal 20061207 1

Nonsense-mediated mRNA decay (NMD) is an mRNA surveillance pathway that recognizes and degrades aberrant mRNAs containing premature stop codons. A critical protein in NMD is Upf1p, which belongs to the helicase super family 1 (SF1), and is thought to utilize the energy of ATP hydrolysis to promote transitions in the structure of RNA or RNA-protein complexes. The crystal structure of the catalytic core of human Upf1p determined in three states (phosphate-, AMPPNP- and ADP-bound forms) reveals an ...[more]

PMID: 17159905

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