Development of Visible Markers for Transgenic Plants and their Availability for Environmental Risk Assessment

Abstract

Monitoring of transgenic plants in the field is important, but risk assessment has entailed laborious use of invisible marker genes. Here, we assessed three easily visible marker transgenes Ð green fluorescent protein (GFP), R, and Nicotiana tabacum homeobox (NTH) 15 genes Ð for their potential use as marker genes for monitoring genetically modified plants. Transgenic Arabidopsis thaliana plants for each of these genes were visibly distinguished from wild-type plants. We determined the germination rate, 3-week fresh weight, time to first flowering, and seed weight of the transgenic plants to evaluate whether the expression of these marker genes affected the growth of the host. Introduction of GFP gene had no effect on the evaluated parameters, and we then used the GFP gene as a marker to assess the outcrossing frequency between transgenic and two Arabidopsis species. Our results showed that the hybridization frequency between transgenic plants and Arabidopsis thaliana was 0.24%, and between transformants and Arabidopsis lyrata it was 2.6% under experimental condition. Out-crossing frequency was decreased by extending the distance between two kinds of plants. Thus, the GFP gene is a useful marker for assessing the whereabouts of transgenes/transformants in the field. We also demonstrated that the GFP gene is possibly applicable as a selection marker in the process of generation of transgenic plants.

Anthocyanin production by over-expression of grape transcription factor gene VlmybA2 in transgenic tobacco and Arabidopsis

“…A versatile gene for anthocyanin production could be a good candidate for a simple and non-destructive visual marker for plant transformation (Ludwig et al 1990;Lloyd et al 1992;Mooney et al 1995;Goldsbrough et al 1996), and may replace controversial antibiotic marker genes. As VlmybA2 shows higher potential than other anthocyanin regulatory genes previously tested (Ludwig et al 1990;Lloyd et al 1992;Mooney et al 1995;Goldsbrough et al 1996;Deluc et al 2006), its potential should be exploited in the genetically modified plant production process, starting from the efficient recovery of regenerants during transformation up to the monitoring of transgenic plants at field level for risk assessment (Tamaoki et al 2006). by a grant to T.K.…”

Biotechnologies and Strategies for Grapevine Improvement

“…In the NCBI taxonomy web portal for V. vinifera, there are 29,971 listed unique coding genes, and the information about these genes and the metabolic pathways in which they are involved are available at the TIGR site [176]. A consensus map was developed based on the genetic maps [177][178][179][180][181] and physical maps [182] previously developed. Other facilities are also available for different genomic and transcriptomic analyses, such as the grape BAC library from the French national resources center for plant genomics [183]; 14,000 transcripts from V. vinifera and 1700 transcripts from other Vitis species were released by The GeneChip® Vitis vinifera genome array (Affymetrix).…”

Grapevine Improvement through Biotechnology

“…Genetic maps have been produced [33,[61][62][63][64], and physical maps are being produced in several laboratories [65] with a consensus map in progress. A grape BAC library is available from the French National Resources Center for Plant Genomics (CNRGV).…”

“…A versatile gene for anthocyanin production could be a good candidate for a simple and nondestructive visual marker during plant transformation [59,60] and may replace controversial antibiotic marker genes. As VlmybA2 shows higher potential than other anthocyanin regulatory genes previously tested, its potential should be exploited in the genetically modified plant production process starting from the efficient recovery of transformants during transformation up to the monitoring of transgenic plants at the field level for risk assessment [61].…”