Ralstonia solanacearum flg22, the causal agent of bacterial wilt, avoids perception by several plants2,3,4. This is probably due to allelic diversification in the flg22 sequence, which causes the development of polymorphisms that avoid recognition by FLS2/BAK5. In addition, this pathogen has acquired polymorphisms that enable it to evade plant PRRs (plant receptors) and induce virulence6.
FLS2 Acquires Binding Activity When Tomato Cells Express a Tag of FLS2:3*myc
FLS2 accumulates in extracts of tomato cells that express a tag of FLS2:3*myc, but does not in extracts from Arabidopsis or nontransformed tomato cells. This is likely due to the fact that expression of FLS2:3*myc results in the formation of tagged functional flg22 binding sites within cytosolic proteins.
TAMRA-flg22 Moves Long Distances via a Flagellin Perception System
In contrast to the default pathway, TAMRA-flg22 leaves endocytic pathways and enters vacuoles, where it binds to endosomes and MVBs. This is probably because TAMRA-flg22 dissociates from FLS2, which activates the flagellar movement protein Y-flg22 to move long distances through vacuoles and vascular tissue (Haupt et al., 2005; Carluccio et al., 2014).
125I-Y-flg22 Mobility Reduces With FLS2 Depletion
The mobility of 125I-Y-flg22 was reduced in Col and fls2 plants to the same extent as Na125I-flg22 (Fig. 3A, B).
125I-Tyr-flg22 Cross-Links to a 175-kD Polypeptide That Is Immunoprecipitated with Anti-FLS2 Antagonists
The immunoprecipitated polypeptide competed for binding of 125I-Tyr-flg22, and