Biotech Updates

GE Tomatoes Over-expressing of Snakin-2 and Extensin-like Protein Genes Show Enhanced Tolerance to Pathogen

April 20, 2011

Scientists Vasudevan Balaji and Christine Smart of Cornell University evaluated the over-expression of two defense proteins (snakin-2 and extensin-like protein) in genetically engineered tomato that confer resistance to bacterial pathogen, Clavibacter michiganensis subsp. michiganensis (Cmm). The pathogen causes bacterial canker and wilt disease that devastate tomato production worldwide. Snakin-2 (SN2) has broad spectrum anti-microbial activity while extensin-like protein (ELP) is involved in plant response to pathogen attack and wounding.

Tomato cultivar known as Mountain Fresh was transformed to contain the SN2 and ELP genes through Agrobacterium tumefaciens. Over-expression of the proteins was confirmed through polymerase chain reaction. Transgenic lines with high levels of SN2 or ELP exhibited increased tolerance to Cmm manifested by late development of wilt symptoms and reduced canker lesions compared to the non-GE lines. Transgenic lines over-expressing SN2 or ELP also exhibited significantly lower bacterial populations than non-transgenic lines.

The researchers concluded that over-expression of SN2 and ELP limits Cmm invasiveness, and could be used for other biotechnological applications involving antibacterial activity.

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