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Modular assembly of chimeric phi29 packaging RNAs that support DNA packaging.

ABSTRACT: The bacteriophage phi29 DNA packaging motor is a protein/RNA complex that can produce strong force to condense the linear-double-stranded DNA genome into a pre-formed protein capsid. The RNA component, called the packaging RNA (pRNA), utilizes magnesium-dependent inter-molecular base-pairing interactions to form ring-shaped complexes. The pRNA is a class of non-coding RNA, interacting with phi29 motor proteins to enable DNA packaging. Here, we report a two-piece chimeric pRNA construct that is fully competent in interacting with partner pRNA to form ring-shaped complexes, in packaging DNA via the motor, and in assembling infectious phi29 virions in vitro. This is the first example of a fully functional pRNA assembled using two non-covalently interacting fragments. The results support the notion of modular pRNA architecture in the phi29 packaging motor.

SUBMITTER: Fang Y

PROVIDER: S-EPMC2504005 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Modular assembly of chimeric phi29 packaging RNAs that support DNA packaging.

Fang Yun Y Shu Dan D Xiao Feng F Guo Peixuan P Qin Peter Z PZ

Biochemical and biophysical research communications 20080602 4

The bacteriophage phi29 DNA packaging motor is a protein/RNA complex that can produce strong force to condense the linear-double-stranded DNA genome into a pre-formed protein capsid. The RNA component, called the packaging RNA (pRNA), utilizes magnesium-dependent inter-molecular base-pairing interactions to form ring-shaped complexes. The pRNA is a class of non-coding RNA, interacting with phi29 motor proteins to enable DNA packaging. Here, we report a two-piece chimeric pRNA construct that is f ...[more]

PMID: 18514064

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