Fig. 6.

Homology models of KAI2 sequences. Models are shown in ribbon representation with the residues that influence the active site cavity shown in stick representation. Cavities are depicted as a transparent surface. Oxygen, nitrogen and sulphur atoms are coloured red, blue and yellow respectively. a The crystal structure of Arabidopsis thaliana KAI2 in complex with karrikin (KAR ₁) is shown in navy blue (PDB code 4JYM). Residue numbers correspond to the unified numbering scheme as in Fig. 5; they are –1 relative to those of A. thaliana KAI2. b–d Liverwort KAI2A homology models are shown in royal blue; b Lejeuneaceae sp. c Lunularia cruciata, d Ptilidium pulcherrimum. e–h Liverwort KAI2B models are shown in turquoise; e Riccia berychiana, f Calypogeia fissa, g Lunularia cruciata, h Marchantia polymorpha. i–l Charophyte KAI2 models are shown in purple; i Klebsormidium subtile, j Chara vulgaris, k Coleochaete scutata, l Coleochaete irregularis. m–o Moss KAI2E/F models are shown in green; m Sphagnum recurvatum KAI2E, n Timmia austriaca KAI2F, o Tetraphis pellucida KAI2F