Deciphering the link between salicylic acid signaling and sphingolipid metabolism

Abstract

The field of plant sphingolipid biology has evolved in recent years. Sphingolipids are abundant in cell membranes, and genetic analyses revealed essential roles for these lipids in plant growth, development, and responses to abiotic and biotic stress. Salicylic acid (SA) is a key signaling molecule that is required for induction of defense-related genes and rapid and localized cell death at the site of pathogen infection (hypersensitive response) during incompatible host–pathogen interactions. Conceivably, while levels of SA rapidly increase upon pathogen infection for defense activation, they must be tightly regulated during plant growth and development in the absence of pathogens. Genetic and biochemical evidence suggest that the sphingolipid intermediates, long-chain sphingoid bases, and ceramides, play a role in regulating SA accumulation in plant cells. However, how signals generated from the perturbation of these key sphingolipid intermediates are transduced into the activation of the SA pathway has long remained to be an interesting open question. At least four types of molecules – MAP kinase 6, reactive oxygen species, free calcium, and nitric oxide – could constitute a mechanistic link between sphingolipid metabolism and SA accumulation and signaling.

Modifications of sphingolipid content affect tolerance to hemibiotrophic and necrotrophic pathogens by modulating plant defense responses in Arabidopsis

“…Collectively, our results suggested that AtDPL1 could be a negative and/or a positive regulator of the JA-and SA-regulated defense pathway, respectively. Whereas a relationship between SA signaling and sphingolipids has often been described (Sánchez-Rangel et al, 2015), our results highlight, to our knowledge for the first time, that sphingolipids could also play a key role in the JA signaling pathway.…”

“…Recently, it was shown that SA and its analog benzothiadiazole affect sphingolipid metabolism (Shi et al, 2015), including AtDPL1 gene expression (Wang et al, 2006). Since activation of the SA-dependent pathway is effective against biotrophic and hemibiotrophic pathogens, it has been postulated that sphingolipids played a key role in defense against such pathogens in an SA-dependent pathway (Sánchez-Rangel et al, 2015). However, whereas acd5, erh1, and the double mutant fah1/fah2 exhibited enhanced resistance to powdery mildew, they displayed a similar phenotype to wild-type plants upon infection with P. syringae pv maculicola or Verticillium longisporum (Wang et al, 2008;König et al, 2012).…”

Molecular Characterization of Rice OsLCB2a1 Gene and Functional Analysis of its Role in Insect Resistance

“…Likewise, a previous study revealed that BPH14 gene confers rice resistance to BPH (Du et al, 2009) and cotton photosynthesis-related gene ( GhPSAK1 ) enhanced SA signaling pathway in transgenic plants (Zhang et al, 2014). Sánchez-Rangel et al (2015) reviewed that sphingolipid played a key role in defense against pathogen in SA-dependent pathway.…”

Involvement of Arabidopsis Hexokinase1 in Cell Death Mediated byMyo-Inositol Accumulation

“…Indeed, how MI accumulation modulates SA biosynthesis and this only in LD conditions remains unknown. An interesting research axis concerns the alteration of ceramides homeostasis since relative accumulation of ceramides and their derivatives appear as key elements for the control of plant PCD via SA-signaling pathway (Sánchez-Rangel et al, 2015). Donahue et al (2010) reported elevated levels of ceramides and of hydroxyceramides in mips1, correlated with the decline of MI and of its derivative phosphatidylinositol.…”