TAC42 is an essential TAC subunit.

(A) Left panels: IF analysis of procyclic T. brucei cells expressing HA-tagged TAC42 (red). DNA is stained with DAPI (blue). Bar, 5 μm. Inset: magnification of the kDNA region. Bar inset, 1 μm. Right panels: IF analysis of isolated flagella of T. brucei cells expressing HA-tagged TAC42. (B) Left graph: growth and loss of kDNA of the procyclic TAC42-RNAi cell line. Red lines depict percentage of cells still having the kDNA. Right graph: fluorescent intensities of kDNA networks were measured after TAC42 knock down. Red lines mark the median. (C) Left graph: growth and loss of kDNA in the bloodstream form TAC42-RNAi cell line. Right graph: growth and loss of kDNA of a TAC42-RNAi cell line from a bloodstream form T. brucei strain that contains a compensatory nuclear mutation (ATPase γ, L262P) that allows it to grow in the absence of kDNA (bloodstream-L262P) [27]. Insets: Northern blots confirming ablation of the TAC42 mRNA in the different RNAi cell lines. Ethidium bromide-stained gel showing the rRNA region is used as a loading control. (D) Transmission electron micrographs showing the kDNA region of uninduced (-Tet) and 2 days induced TAC42-RNAi cells (+Tet). Bar: 200 nm.