Figure 1. Naegleria has flagellate and mitotic microtubule arrays composed of distinct tubulins.

(A) The evolutionary relationships between Naegleria and other eukaryotes are shown using a cladogram (branch lengths are meaningless) modified from Velle and Fritz-Laylin.¹⁵

(B) Amoebae from a growing population (left) or flagellates from a differentiated population (right) were fixed and stained with antibodies (anti-α-tubulin clone DM1A, green) and tubulin Tracker (fluorescent docetaxel, cyan) to detect microtubules and Alexa Fluor 488 conjugated Phalloidin to label F-actin (magenta). Maximum intensity projections of cells are shown.

(C) The evolutionary relationship of γ-, α-, and β-tubulins from the species in (A) are shown using a cladogram (using the color scheme from A; see Data S2 for the full tree). The tree is rooted on gamma tubulins, and shows mitotic (green) and flagellate (blue) tubulins from Naegleria (closed circles) and Acrasis (open circles).

(D) The fold changes in tubulin mRNA in amoebae compared with flagellates (top) or flagellates compared with amoebae (bottom) were calculated from data reported in Fritz-Laylin and Cande (from 3 experimental replicates encompassing 6 technical replicates).¹⁶ Each point represents one experimental replicate, and lines denote the average ± standard deviation (SD). Tubulins are labeled with JGI identification numbers.

See also Figure S1, Data S1, S2, S3, S4, S5, and S6, and Tables S2 and S3.