Biotech Updates

Overexpression of Soybean SAMT gene Confers Resistance to Soybean Cyst Nematode

November 27, 2013

Salicylic acid is plays an important function in turning on plant defense mechanisms during pathogen attack. Salicylic acid methyltransferase (SAMT) regulates the amount of salicylic acid by converting salicylic acid to methyl salicylate University of Tennessee scientist Jungyu Lin and colleagues reported that SAMT gene from soybean (GmSAMT1) plays a significant function in the plant's defense against soybean cyst nematode. The researchers isolated full-length cDNAs of GmSAMT1 from a nematode-resistant soybean line and from a nematode-susceptible soybean line. The two cDNAs encode proteins of identical sequences. The GmSAMT1 cDNA was expressed in Escherichia coli. Analysis confirmed that E. coli-expressed GmSAMT1 function as salicylic acid methyltransferase.

To verify the function of GmSAMT1 in soybean defense against soybean cyst nematode, genetically engineered hairy roots overexpressing GmSAMT1 were developed and tested for soybean cyst nematode resistance. Overexpression of GmSAMT1 in nematode-susceptible backgrounds significantly decreased the development of soybean cyst nematode, which implies that overexpression of GmSAMT1 in the GE hairy root system could confer resistance to soybean cyst nematode. It was also found that overexpression of GmSAMT1 in GE hairy roots has an effect in the expression of selected genes involved in salicylic acid production and salicylic acid signal transduction.

Read more results at Plant Biotechnology Journal: