Mapping FLS2 function to structure: LRRs, kinase and its working bits.
The plasma membrane-localised FLAGELLIN SENSING 2 (FLS2) receptor is an important component of plant immunity against potentially pathogenic bacteria, acting to recognise the conserved flg22 peptide of flagellin. FLS2 shares the common structure of transmembrane receptor kinases with a receptor-like ectodomain composed of leucine-rich repeats (LRR) and an active intracellular kinase domain. Upon ligand binding, FLS2 dimerises with the regulatory LRR-receptor kinase BRI1-associated kinase 1, which in turn triggers downstream signalling cascades. Although lacking crystal structure data, recent advances have been made in our understanding of flg22 recognition based on structural and functional analyses of FLS2. These studies have revealed critical regions/residues of FLS2 and post-translational modifications that regulate the abundance and activity of this receptor. In this review, we present the current knowledge on the structural mechanism of the FLS2-flg22 interaction and subsequent receptor-mediated signalling.
The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH, UK. robatzek@tsl.ac.uk
Silke
S
Robatzek
Lennart
L
Wirthmueller
D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000276:immunology / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000502:physiology; D020134:Catalytic Domain; D005408:Flagellin / Q000276:immunology; D006031:Glycosylation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000382:microbiology; D057865:Plant Immunity; D011485:Protein Binding; D011494:Protein Kinases / Q000737:chemistry* / Q000502:physiology; D011499:Protein Processing, Post-Translational; D017433:Protein Structure, Secondary; D051192:Receptors, Pattern Recognition / Q000737:chemistry* / Q000502:physiology; D015398:Signal Transduction / Q000276:immunology
D029681:Arabidopsis Proteins; D051192:Receptors, Pattern Recognition; D005408:Flagellin; D011494:Protein Kinases; C411853:FLS2 protein, Arabidopsis