Table 2.

Model of antiviral response of Chelidonium majus latex based on in vitro studies, which represents preformed immediate defense response with exuding latex. 1st line of defense-after mechanical damage (e.g., herbivore bite) the latex exudes and due its stickiness clots and stops or kills the herbivore. 2nd line of defense-cell wall damage is the prerequisite for the possibility of viral infection. Thereafter it can be stopped by oxidative burst and antiviral response (3rd line of defense). Abbreviations: PPO–polyphenol oxidase; LOX-lipoxygenase; POX-peroxidase; MLP-major latex protein; GRP-glycine-rich protein. According to [74].

Line of Defense	Type of Action	Predominant Proteins and Compounds
1st	Mechanical damage	PPO, LOX (latex stickiness, different chemicals)
2nd	Oxidative burst	POX, LOX et al.
3rd	Antiviral activity	MLP, GRP (RNase/DNase activity, nucleic acid binding)