Fig. 4From: Evolutionary characterization and transcript profiling of β-tubulin genes in flax (Linum usitatissimum L.) during plant developmentSimilarity tree of plant β-tubulins. Maximum likelihood analysis was performed on the complete β-tubulin sets of flax, aspen, cotton, Arabidopsis, Medicago, barley, rice and maize. Accession numbers are listed in Additional file 2. The β-tubulin of the green alga C. reinhardtii was used as an outgroup. Close circles indicate flax tubulins. Open circles indicate the nodes of the four tubulin classes. Grey background indicates monocot tubulin cladesBack to article page