Figure 2.

Phylogenetic analysis of plant and algal Gα proteins. Maximum likelihood phylogenetic tree of Gα proteins from all available plant and algal sequences, excluding eudicots. A, Phylogenetic tree from publicly available genomes. Monomeric GTPase (ARF) sequence from Arabidopsis is used as outgroup. Many nodes are collapsed and labeled with triangles to improve readability. The total number of sequences in each collapsed node is mentioned in their respective tip label inside the curly bracket. Tree scale, 0.3 amino acid substitution per site. B, Phylogenetic tree constructed using the Gα sequences from publicly available genomes and transcriptomes. Human Gα sequences are used as outgroup. The branch length of jgi_Chloropicon_primus is plotted as 0.5 instead of the actual value 3.0526289 to improve the view of the tree. Tree scale 0.1 amino acid substitution per site. In both trees, each plant lineage is highlighted and labeled in different colors. Bootstrap support values >40% are shown at each node (1,000 bootstrap replicates). Star marks the gene duplication events inferred from the tree topology. Clades of Gα gene tree conflicting with the species tree are labeled in red.