[Obtaining marker-free transgenic soybean plants with optimal frequency by constructing three T-DNAs binary vector].

Area of Science:

• Plant Biotechnology
• Molecular Biology
• Genetics

Context:

• Transgenic crops require efficient methods for marker gene removal to facilitate environmental release and regulatory approval.
• The development of novel binary vectors is essential for improving the efficiency and safety of genetic modification in crops.

Purpose:

• To construct and evaluate a novel binary vector (pNB35SVIP1) with three T-DNAs for the efficient generation of marker-free transgenic soybean plants.
• To assess the co-transformation efficiency of the bar and VIP1 genes and the frequency of marker gene elimination in transgenic soybean.

Summary:

• A binary vector containing one bar gene and two VIP1 gene expression cassettes was constructed and used to transform soybean (Glycine max) via Agrobacterium EHA101.
• Transgenic soybean plants were obtained with an efficiency of 0.83%-3.16%, achieving a co-transformation efficiency of 86.4%.
• Analysis of T1 progenies revealed marker-free plants at a frequency of 7.6%, with significant rates of alien gene loss (22.7%) and gene silencing (bar gene: 27.3%, VIP1 gene: 37.1% in marker-free plants).

Impact:

• The study demonstrates the potential of the three T-DNA plasmid as an ideal vector for generating marker-free genetically modified organisms.
• This approach can accelerate the environmental release and commercialization of transgenic crops by simplifying regulatory processes.
• Findings contribute to the development of safer and more efficient plant genetic engineering strategies.