title: Contribution of the zinc finger to zinc and DNA binding by a suppressor of posttranscriptional gene silencing.
abstract: The zinc finger C(36)-X1-C(38)-X7-C(46)-X6-H(53) of the nuclearly localized C2 protein of Tomato yellow leaf curl virus China is involved in pathogenicity and suppression of posttranscriptional gene silencing (PTGS). Here, we demonstrate that the zinc finger is indispensable for the C2 protein to bind zinc and DNA. Mutation of cysteine residue C(36), C(38), or C(46) reduced the zinc and DNA binding capacity of C2 protein. When expressed from potato virus X, all three mutants, C2-C(36)R, C2-C(38)N, and C2-C(46)I, tagged with a green fluorescent protein (GFP) were still capable of transporting GFP into but aggregated abnormally in nuclei. Our data establish that zinc- and DNA-binding activity correlates with C2-mediated pathogenesis and PTGS suppression.
authors.affiliation: Horticulture Research International, East Malling, West Malling, Kent ME19 6BJ, United Kingdom.
authors.forename: Rene
authors.initials: R
authors.lastname: Van Wezel
authors.forename: Huanting
authors.initials: H
authors.lastname: Liu
authors.forename: Zirong
authors.initials: Z
authors.lastname: Wu
authors.forename: John
authors.initials: J
authors.lastname: Stanley
authors.forename: Yiguo
authors.initials: Y
authors.lastname: Hong
mesh_terms: D004247:DNA / Q000378:metabolism*; D017791:Geminiviridae / Q000472:pathogenicity*; D018551:Solanum lycopersicum / Q000821:virology*; D034622:RNA Interference; D013329:Structure-Activity Relationship; D014764:Viral Proteins / Q000737:chemistry / Q000502:physiology*; D015032:Zinc / Q000378:metabolism*; D016335:Zinc Fingers
chemical_list: D014764:Viral Proteins; D004247:DNA; D015032:Zinc