Fertile transgenic barley generated by direct DNA transfer to protoplasts

Area of Science:

• Plant Biotechnology
• Molecular Biology
• Genetics

Background:

• Barley (Hordeum vulgare L.) is a vital cereal crop.
• Efficient genetic transformation methods are crucial for crop improvement.
• Protoplast-based transformation offers a potential route for barley genetic engineering.

Purpose of the Study:

• To establish a polyethylene glycol (PEG)-mediated transformation protocol for barley protoplasts.
• To generate transgenic barley plants expressing the neomycin phosphotransferase (NPT II) gene.
• To assess the stability and heritability of the introduced gene.

Main Methods:

• Isolation of embryogenic barley protoplasts.
• Polyethylene glycol (PEG)-mediated direct DNA uptake of a plasmid containing the NPT II gene.
• Selection of transformed cells using the antibiotic G418.
• Regeneration of shoots and plantlets from selected calli.
• Analysis of gene expression and integration using NPT II ELISA and Southern hybridization.

Main Results:

• Development of embryogenic calli and shoots from PEG-treated barley protoplasts.
• Approximately 50% of morphogenic calli expressed the foreign NPT II gene.
• Twelve transgenic plantlets were successfully established in soil.
• Stable integration of the transgene was confirmed by Southern hybridization.
• The foreign gene was transmitted and expressed in the progeny of most transgenic plants, although inactivation was observed in one line.

Conclusions:

• PEG-mediated direct DNA uptake is an effective method for generating transgenic barley plants.
• The NPT II gene can be stably integrated and heritably expressed in barley.
• This transformation system provides a valuable tool for genetic studies and crop improvement in barley.