This is confirmed by Alpha-1-antichymotrypsin's role as a protease inhibitor in the defence against degradation by proteases in the lower respiratory airways [25].
The differentially modulated proteins could be grouped into the following five different functional classes: photosynthesis and energy metabolism, carbohydrate metabolism, protein biosynthesis and degradation, defence responses and secondary metabolism.
To that respect, it should be noted that activation of plant defence genes by pectin degradation products is well documented [41], [42].
More than 26 cellular pathways, ranging from DNA replication to transcription, metabolism, protein degradation, plant defence, and developmental regulation, have been found to be redundantly regulated by all light signals [35].
Protein spots were characterized by LC-MS/MS analysis and found to be involved in photosynthesis and energy metabolism, carbohydrate metabolism, protein degradation and defence.
Though the above mentioned protease genes induced by PPV infection are known to function in the protein degradation, plant defence responses and hypersensitive reactions [ 45- 47], their exact roles in PPV infection are to be elucidated.
Hyphal deformations of Aspergillus due to the presence of the bacteria were observed, coinciding with altered expression of genes related to lipid and cell wall degradation, cell defence and nitrogen deficiency.
In plants, beta-glycosidases serve a number of diverse and important functions, including bioactivation of defence compounds, cell wall degradation in endosperm during seed germination, activation of phytohormones, and lignifications [ 73].
The other three criteria dealing with the level of induced defence responses and pectin degradation were ranked based on the statistical classes given at 6 dpi for the aggressive isolates and at 12 dpi for the weak and non-aggressive isolates (Figs. 4B, 4C & 5B).
Indeed, since most birds are likely to have a relapse infection, the low tGSH in old P. relictum infected birds can be a result of a more rapid decline of the antioxidant defences (or indirectly via degradation of other cellular mechanisms affecting GSH synthesis) compared to uninfected ageing birds.
