2ZI0

Crystal structure of Tav2b/siRNA complex

Summary for 2ZI0

• Entry DOI: 10.2210/pdb2zi0/pdb
• Descriptor: Protein 2b, RNA (5'-D(P*AP*GP*AP*CP*AP*GP*CP*AP*UP*UP*AP*UP*GP*CP*UP*GP*UP*CP*UP*UP*U)-3') (3 entities in total)
• Functional Keywords: rnai suppression, nucleus, suppressor of rna silencing, gene regulation-rna complex, gene regulation/rna
• Biological source: Tomato aspermy virus (TAV)
• Cellular location: Host nucleus (By similarity): Q8UYT3
• Total number of polymer chains: 4
• Total formula weight: 31585.88

Authors

Yuan, Y.A.,Chen, H.-Y. (deposition date: 2008-02-12, release date: 2008-07-22, Last modification date: 2024-10-16)

Primary citation

Chen, H.-Y.,Yang, J.,Lin, C.,Yuan, Y.A.
Structural basis for RNA-silencing suppression by Tomato aspermy virus protein 2b
Embo Rep., 9:754-760, 2008

PubMed Abstract: The 2b proteins encoded by cucumovirus act as post-transcriptional gene silencing suppressors to counter host defence during infection. Here we report the crystal structure of Tomato aspermy virus 2b (TAV2b) protein bound to a 19 bp small interfering RNA (siRNA) duplex. TAV2b adopts an all alpha-helix structure and forms a homodimer to measure siRNA duplex in a length-preference mode. TAV2b has a pair of hook-like structures to recognize simultaneously two alpha-helical turns of A-form RNA duplex by fitting its alpha-helix backbone into two adjacent major grooves of siRNA duplex. The conserved pi-stackings between tryptophan and the 5'-terminal base of siRNA duplex from both ends enhance the recognition. TAV2b further oligomerizes to form a dimer of dimers through the conserved leucine-zipper-like motif at its amino-terminal alpha-helix. Biochemical experiments suggest that TAV2b might interfere with the post-transcriptional gene silencing pathway by directly binding to siRNA duplex.

PubMed: 18600235
DOI: 10.1038/embor.2008.118

Experimental method

X-RAY DIFFRACTION (2.82 Å)