Discovered in 1984, lipoxins ( LXS ) form , together with other metabolites of arachidonic acid autakoidów large group collectively eicosanoids . Of the three best known biosynthetic pathways lipoxins ( LXA4 and LXB4 ) , catalyzed by a two sequentially acting 12/15-lipoksygenazę 5 -i and the third initiated by aspirin acetylated cyclooxygenase- 2 and generates a 15- epimers of lipoxins ( 15R - LXA4 and B4) . Unlike other eicosanoids , lipoxins are mainly produced by two cooperating with each cell , such as neutrophils and platelets .

Phenomena characteristic of plant resistance are known. hypersensitivity reaction (called: hypersensitive Response, HR), leading to death of the cells in contact with the pathogen, and often developing in the following system acquired resistance (called: Systemic Acquired Resistance SAR). Both the occurrence of HR and SAR development are conditioned by activation of transcription of genes. Trails linking receptors with gene expression are the subject of the second part of the article.

Immune mechanisms of higher plants are characterized by high diversity. The consequence is sometimes in contact with the pathogen production of reactive oxygen species, cell wall modification, the local cell death with characteristics of apoptosis, production of phytoalexins and pathogenesis associated proteins (PR). Elicitors are compounds directly responsible for the induction of immune responses of plants. Among the effectors produced by micro-organisms can be distinguished elicitors specific to a particular strain of the pathogen and those commonly found in many pathogens.