Previous studies have identified a number of pathogenesis-related (PR) proteins in the xylem sap (e.g. PR1a, PR5; [ 25, 52]).
NPR1 is involved in the regulation of the transcription of a number of pathogenesis-related (PR) genes (Pieterse et al. 1998; Zhang et al. 1999).
Overexpression of the Arabidopsis ATAF2 gene in transgenic lines led to repression of a number of pathogenesis-related protein genes, whereas their levels were increased in ATAF2 knock-out lines [ 77].
The observation that a number of pathogenesis-related (PR) genes are induced during leaf senescence has lead to the suggestion that the senescence program might have incorporated features of the pathogen-defense response to protect the senescing leaf against opportunistic pathogens [ 73].
Since defects in vacuolar function result in a number of abnormal pathogenesis-related phenotypes, we visualized the vacuolar integrity by using the fluorescent dyes FM4-64 and CMAC.
In addition, it is a well characterised model, having been used to study skeletal muscle regeneration in a number of contexts including pathogenesis of the dystrophinopathies, angiogenesis, exercise and pharmacodynamics (Grounds et al., 2005; Morgan et al., 1989; Roberts and McGeachie, 1990; Roberts and McGeachie, 1992a; Roberts and McGeachie, 1992b; Roberts and McGeachie, 1994).
In each of these studies, significant changes were seen to occur in the rice transcriptome in response to infection, with a number of genes encoding pathogenesis-related functions seen to be differentially expressed [ 13, 14].
SAR requires the accumulation of SA, and this is associated with an increased expression of a large number of pathogenesis-related genes (PR genes) in both local and systemic tissues.
Whereas some pathogenesis-related proteins, chitinases, non-specific lipid transfer proteins, an allergen protein, and a gene encoding alpha-hydroxynitrile lyase (TC48696) were repressed in their mRNA expression following water-deficit treatment, a larger number of pathogenesis-related proteins exhibited increased mRNA expression (Additional file 4, Table 19).
These findings have a number of implications for viral pathogenesis.
Of these, the cytokines IL-1 and TNFα have been the focus of a number of studies investigating the pathogenesis of IVD degeneration, herniation and sciatic pain [ 11- 20].
