Crop Biotech Update

Scientists Conduct Functional Characterization of Powdery Mildew Susceptibility Gene in Eggplant

January 18, 2017

Scientists from Wageningen University and Research Centre and partners conducted a functional characterization of the powdery mildew (PM) susceptibility gene SmMLO1 in eggplant to help other researchers in developing PM resistant eggplant varieties.

Eggplant, an important vegetable, can be a host of fungal species that can cause powdery mildew disease. Some copies of the Mildew Locus (MLO) gene family are PM susceptibility factors because their loss of function leads to mlo resistance. In a previous study conducted by Valentina Bracuto and colleagues, MLO homolog from eggplant, SmMLO1, was successfully isolated. Though SmMLO1 is closely related to MLO susceptibility genes present in other species, it exhibits a unique non-synchronous amino acid substitution particularly in protein position 422.

The follow up study showed that transgenic overexpression of SmMLO1 in tomato compromised resistance to the PM pathogen, which indicates that SmMLO1 is a PM susceptibility factor in eggplant. Furthermore, PM susceptibility returned during expression of a synthetic gene, s-SmMLO1, encoding a protein identical to SmMLO1, except for the presence of T at position 422. This shows that the amino acid change does not affect the protein role as PM susceptibility factor.

Read the research article in Transgenic Research.