Correlated Expression of gfp and Bt cry1Ac Gene Facilitates Quantification of Transgenic Hybridization between Brassicas

B.-C. Shen; C. N. Stewart; M.-Q. Zhang; Y.-T. Le; Z.-X. Tang; X.-C. Mi; W. Wei; K.-P. Ma

doi:10.1055/s-2006-924277

Plant Biology, Inhaltsverzeichnis

Plant Biol (Stuttg) 2006; 8(5): 723-730
DOI: 10.1055/s-2006-924277

Short Research Paper

Georg Thieme Verlag Stuttgart KG · New York

Correlated Expression of gfp and Bt cry1Ac Gene Facilitates Quantification of Transgenic Hybridization between Brassicas

B.-C. Shen¹ ^, ² , C. N. Stewart³ Jr. , M.-Q. Zhang² , Y.-T. Le¹ , Z.-X. Tang¹ , X.-C. Mi¹ , W. Wei¹ , K.-P. Ma¹

¹Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Science, Beijing 100093, China
²Key Laboratory of Eco-physiology and Genetic Improvement for Sugarcane, Ministry of Agriculture, Fujian Agricultural and Forestry University, Fuzhou 350002, China
³Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996-4561, USA

Abstract

Gene flow from transgenic oilseed rape (Brassica napus) might not be avoidable, thus, it is important to detect and quantify hybridization events with its relatives in real time. Data are presented showing the correlation between genetically linked green fluorescent protein (GFP) with Bacillus thuringiensis (Bt) cry1Ac gene expression in hybrids formed between transgenic B. napus “Westar” and a wild Chinese accession of wild mustard (B. juncea) and hybridization between transgenic B. napus and a conspecific Chinese landrace oilseed rape. Hybrids were obtained either by spontaneous hybridization in the field or by hand-crossing in a greenhouse. In all cases, transgenic hybrids were selected by GFP fluorescence among seedlings originating from seeds harvested from B. juncea and the Chinese oilseed rape plants. Transgenicity was confirmed by PCR detection of transgenes. GFP fluorescence was easily and rapidly detected in the hybrids under greenhouse and field conditions. Results showed that both GFP fluorescence and Bt protein synthesis decreased as either plant or leaf aged, and GFP fluorescence intensity was closely correlated with Bt protein concentration during the entire vegetative lifetime in hybrids. These findings allow the use of GFP fluorescence as an accurate tool to detect gene-flow in time in the field and to conveniently estimate Bt cry1Ac expression in hybrids on-the-plant.

Key words

Brassica napus - Brassica juncea - GFP-Meter - transgene monitoring - Bt protein concentration - hybridization frequency.

Volltext

Referenzen

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W. Wei

Laboratory of Quantitative Vegetation Ecology
Institute of Botany
Chinese Academy of Science

Beijing 100093

China

eMail: weiwei@ibcas.ac.cn

Editor: R. Mendel