Characterization of the promoter of Grapevine vein clearing virus

Abstract

Grapevine vein clearing virus (GVCV) is a recently discovered DNA virus in grapevine that is closely associated with the grapevine vein clearing syndrome observed in vineyards in Missouri and surrounding states. The genome sequence of GVCV indicates that it belongs to the genus Badnavirus in the family Caulimoviridae. To identify the GVCV promoter, we cloned portions of the GVCV large intergenic region in front of a GFP gene present in an Agrobacterium tumefaciens binary vector. GFP expression was assessed by ELISA 3 days after agroinfiltration of Nicotiana benthamiana leaves. We found that the GVCV DNA segment between nts 7332 and 7672 directed expression of GFP and this expression was stronger than expression using the Cauliflower mosaic virus 35S promoter. It was revealed by 59 and 39 RACE that transcription was initiated predominantly at nt 7571 and terminated at nt 7676.

A Natural Reservoir and Transmission Vector of Grapevine Vein Clearing Virus

“…NC015784) contains a double-stranded, circular DNA molecule of 7,753 bp. Three open reading frames (ORFs) are predicted on the plus-strand of the genome whose functions have not yet been fully characterized, except for the analogous annotation on the basis of functional motifs (Zhang et al 2015). Nucleotide diversity within a GVCV population is in a range of 0.15 to 2.00% (Howard and Qiu 2017), and GVCV populations show diverse genetic variations among Vitis spp.…”