Figure 4. Relationship between formation of cellular components and cell-cycle regulated gene expression.

Right: summary of functions of upregulated genes as suggested by GO analysis. Left: Representation of procyclic T. brucei cells progressing through the cell cycle. K: the kinetoplast (organelle containing the mtDNA, which consists of many circular DNA molecules). N: Nucleus. B: Basal body (blue rectangle) and pro-basal body (red rectangle). In light pink is the mitochondrion; in green is the old flagellum, which emerges from the posterior end of the cell (left) but is tethered to the dorsal side of the cell along its length. In late G1 phase the probasal body (small red rectangle) matures into a new basal body which will localize the base of the new flagellum, and the kinetoplast is already in S-phase. In S-phase, the new flagellum (orange) begins to elongate, anchored to the old flagellum by a mobile flagellar connector structure (orange circle) [34], while the kinetoplasts and basal bodies separate. After DNA replication an intranuclear mitotic spindle forms (pink line) and cells enter mitosis. Before cytokinesis, the Chromosomal Passenger Complex relocates from the spindle to the cell anterior (pink circle, bottom panel) where it moves with the cytokinetic furrow from anterior to posterior (dotted line) [48].