De novo formation of basal bodies during cellular differentiation of Naegleria gruberi: progress and hypotheses.

Under defined laboratory conditions, Naegleria gruberi undergo an amoeba-to-flagellate differentiation. During this differentiation, N. gruberi changes its shape from an amorphous amoeba to a regular shaped flagellate and forms de novo a flagellar apparatus, which is composed of two basal bodies, two flagella, a flagellar rootlet, and cytoplasmic microtubules. The entire process is accomplished within 2h after initiation of differentiation and more than 95% of cells in the population undergo this differentiation. This rapid and synchronous differentiation of N. gruberi provides us with a unique system in which we can study the process of de novo basal body assembly. In this review, I summarize recent findings associated with de novo basal body assembly and propose a hypothesis to explain how N. gruberi assemble two basal bodies per cell, which is what happens in the majority of cells.