Fig. 5: Azolla–cyanobacterial symbiosis.
From: Fern genomes elucidate land plant evolution and cyanobacterial symbioses
a, The cyanobiont phylogeny largely mirrors the host species phylogeny, indicating a convincing cospeciation pattern between the two partners. All nodes received a maximum likelihood bootstrap support of 100%, and for the host phylogeny, all nodes also received a local posterior probability of 1.0 from the ASTRAL119 analysis. Both the nuclear and the plastome data sets gave the same topology for the host, and the branch lengths shown here were from the plastome tree. Scale bars represent 0.01 substitutions per site. b, The CSP genes were lost in the Azolla and Salvinia genomes (empty boxes), whereas orthologues can be found in other fern transcriptomes (red boxes). *Arabidopsis lacks the CSP genes and does not have AM symbiosis. c, Cyanobionts have a large effect on the Azolla transcriptome. d, The Azolla transcriptome responds to nitrogen starvation more significantly when cyanobionts are absent than when they are present. PC, principal component. e, Candidate genes involved in nutrient transport and communication with cyanobionts.
