|Moran-diez, Maria - Texas A&m University|
|Horowitz, Benjamin - Israel Institute Of Technology|
|Mukherjee, Prasun - Texas A&m University|
|Kenerley, Charles - Texas A&m University|
Submitted to: Fungal Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/19/2015
Publication Date: 2/14/2015
Citation: Crutcher, F.K., Moran-Diez, M.E., Liu, J., Horowitz, B.A., Mukherjee, P.K., Kenerley, C.M. 2015. A paralog of the proteinaceous elicitor sm1 affects colonization of maize roots by Trichoderma virens. Fungal Biology. 119(6):476-486. Interpretive Summary: Small proteins produced by certain fungi, called biocontrol agents, have previously been found to provide resistance to plants from microorganisms that cause plant disease (i.e., plant pathogens). Identification of these proteins can greatly increase our understanding of how biocontrol agents control disease; this could lead to new options to control plant pathogens. One such protein was identified and characterized. It was found that although this protein had no role in initiating plant resistance to pathogens, it was involved in the physical interaction between the biocontrol agent and the plant. When physical contact between the plant and the biocontrol agent was lost, there was an increased production of another closely related protein in the biocontrol agent known to stimulate plant defenses. We concluded that these closely related proteins work together to benefit both the plant and the biocontrol fungus. The study of how plants interact with beneficial organisms could lead to more effective biocontrol agents, giving farmers alternative options to pesticides.
Technical Abstract: The biocontrol agent, Trichoderma virens, has the ability to protect plants from pathogens by eliciting plant defense responses, involvement in mycoparasitism, or secreting antagonistic secondary metabolites. SM1, an elicitor of induced systemic resistance (ISR), was found to have three paralogs within the T. virens genome. The paralog sm2 is highly expressed in the presence of plant roots. Gene deletion mutants of sm2 were generated and compared with the wild type for the ability to interact with plant roots. Wild-type and sm2 deletion mutants similarly elicited ISR in maize against Colletotrichum graminicola, but deletion strains had a significantly lowered ability to colonize maize roots. Understanding the roles of elicitor protein families can increase our understanding of plant-microbe interactions and provide approaches to controlling plant diseases.