A chloroplast protein binds a viroid RNA in vivo and facilitates its hammerhead-mediated self-cleavage.

ABSTRACT: Viroids, small single-stranded circular RNAs (246-401 nucleotides), do not have mRNA capacity and must recruit host proteins to assist in the steps of their biological cycle. The nature of these cellular factors is poorly understood due to a lack of reliable experimental approaches. Here, to screen for host proteins interacting with viroid RNAs in vivo, we UV-irradiated avocado leaves infected with avocado sunblotch viroid (ASBVd), the type member of chloroplast viroids containing hammerhead ribozymes. This resulted in the detection of several ASBVd-host protein adducts. Tandem mass spectrometry analysis of the most abundant cross-linked species identified the protein component as two closely related chloroplast RNA-binding proteins (PARBP33 and PARBP35) of a family whose members previousl

SUBMITTER: Daros JA 

PROVIDER: S-EPMC125856 | biostudies-literature | 2002 Feb

REPOSITORIES: biostudies-literature