title: Regulation of primary plant metabolism during plant-pathogen interactions and its contribution to plant defense.
abstract: Plants are constantly exposed to microorganisms in the environment and, as a result, have evolved intricate mechanisms to recognize and defend themselves against potential pathogens. One of these responses is the downregulation of photosynthesis and other processes associated with primary metabolism that are essential for plant growth. It has been suggested that the energy saved by downregulation of primary metabolism is diverted and used for defense responses. However, several studies have shown that upregulation of primary metabolism also occurs during plant-pathogen interactions. We propose that upregulation of primary metabolism modulates signal transduction cascades that lead to plant defense responses. In support of this thought, we here compile evidence from the literature to show that upon exposure to pathogens or elicitors, plants induce several genes associated with primary metabolic pathways, such as those involved in the synthesis or degradation of carbohydrates, amino acids and lipids. In addition, genetic studies have confirmed the involvement of these metabolic pathways in plant defense responses. This review provides a new perspective highlighting the relevance of primary metabolism in regulating plant defense against pathogens with the hope to stimulate further research in this area.
authors.affiliation: Plant Biology Division, The Samuel Roberts Noble Foundation Ardmore, OK, USA.
authors.forename: Clemencia M
authors.initials: CM
authors.lastname: Rojas
authors.affiliation: Plant Biology Division, The Samuel Roberts Noble Foundation Ardmore, OK, USA ; National Institute of Plant Genome Research, Jawaharlal Nehru University Campus New Delhi, India.
authors.forename: Muthappa
authors.initials: M
authors.lastname: Senthil-Kumar
authors.affiliation: Plant Biology Division, The Samuel Roberts Noble Foundation Ardmore, OK, USA ; Boyce Thompson Institute for Plant Research Ithaca, NY, USA.
authors.forename: Vered
authors.initials: V
authors.lastname: Tzin
authors.affiliation: Plant Biology Division, The Samuel Roberts Noble Foundation Ardmore, OK, USA.
authors.forename: Kirankumar S
authors.initials: KS
authors.lastname: Mysore
keywords: avirulent pathogens; hypersensitive response; plant defense; primary metabolism; programmed cell death; virulent pathogens