Expression of an apoplast-directed, T-phylloplanin-GFP fusion gene confers resistance against Peronospora tabacina disease in a susceptible tobacco

Abstract

Tobaccos and certain other plants secrete phylloplanin glycoproteins to aerial surfaces where they appear to provide first-point-of-contact resistance against fungi/fungi-like pathogens. These proteins can be collected by water washing of aerial plant surfaces, and as shown for tobacco and a sunflower phylloplanins, spraying concentrated washes onto, e.g., turf grass aerial surfaces can provide resistance against various fungi/fungi-like pathogens, in the laboratory. These results suggest that natural-product, phylloplanins may be useful as broad-selectivity fungicides. An obvious question now is can a tobacco phylloplanin gene be introduced into a disease-susceptible plant to confer endogenous resistance. Here we demonstrate that introduction of a tobacco phylloplanin gene--as a fusion with the GFP gene--targeted to the apoplasm can increase resistance to blue mold disease in a susceptible host tobacco.

A Region Containing an as-1 Element of Dahlia Mosaic Virus (DaMV) Subgenomic Transcript Promoter Plays a Key Role in Green Tissue- and Root-Specific Expression in Plants

“…DaMV contains a circular double-stranded DNA of approximately 8 kb, with four single-stranded interruptions (Richins and Shepherd 1983) and six genes (http://dahlia.wsu.edu/ vectorcontrol/whatsknowndmv.htm). Generally, two major transcriptional promoters are present in most of the caulimovirus genome; these two promoters are the fulllength transcript (Flt) and the subgenomic transcript (Sgt) promoters, which have been studied previously in cauliflower mosaic virus (CaMV), figwort mosaic virus (FMV), peanut chlorotic streak virus (PClSV), strawberry vein mosaic virus (SVMV), and mirabilis mosaic virus (MMV) (Bhattacharyya et al 2002;Maiti et al 1997;Maiti and Shepherd 1998;Odell et al 1981;Pattanaik et al 2004;Dey and Maiti 1999;Sahoo et al 2009Sahoo et al , 2013Kroumova et al 2013;. Similarly, our recent data (Sahoo et al 2014b) also revealed that the DaMV genome possesses the Flt and Sgt promoters.…”

pSiM24 Is a Novel Versatile Gene Expression Vector for Transient Assays As Well As Stable Expression of Foreign Genes in Plants

“…The RB and LB are considered to be the only essential cis-elements for T-DNA transfer [54]. The promoter carried by the expression cassettes described here has been studied in transgenic plants (present study) and is also functional in plants such as tobacco [41]–[44], [55], Arabidopsis and corn (Sahoo and Maiti, Unpublished Data). It has been documented that the Mirabilis mosaic virus full-length transcript promoter is constitutive in nature, exhibiting 14 to 25 times stronger activity than CaMV35S in the tobacco protoplast transient system and transgenic tobacco plants, respectively [27], [34], [42].…”

“…It has been documented that the Mirabilis mosaic virus full-length transcript promoter is constitutive in nature, exhibiting 14 to 25 times stronger activity than CaMV35S in the tobacco protoplast transient system and transgenic tobacco plants, respectively [27], [34], [42]. The modified full-length transcript promoter (M24) of the Mirabilis mosaic virus with duplicated enhancer domains [27], [29], [41]–[44], [55] was used in the pSiM24 vector to evaluate gene expression in plants. In the pSiM24-GUS vector, the coding sequence of GUS was placed between the heterologous M24 promoter and the terminator sequence from the rbcSE9 gene (Figure 1) [43]–[44].…”

“…Suspensions of the A. tumefaciens strain GV3850 bearing pSiM24 and pSiM24-GUS constructs were prepared as previously described [35], and the infiltration procedure was conducted following a previously reported protocol [41]. Leaves of N. benthamiana were weighed and submerged in a suspension of A. tumefaciens strain GV3850 bearing pSiM24 or pSiM24-GUS plasmids.…”

“…Leaves of N. benthamiana were weighed and submerged in a suspension of A. tumefaciens strain GV3850 bearing pSiM24 or pSiM24-GUS plasmids. A vacuum level of 760 mm Hg was applied and released several times until the leaves became translucent [41]. Leaves were transferred into MS-media-containing plates and incubated at room temperature for two days.…”