Fig. 4. PACRG AB RNAi induction causes loss of outer-doublet microtubules. (A) Transmission electron microscopy images of TbPACRG AB non-induced cells (a) and RNAi-induced cells 72 hours after induction (b-d). Note the loss of variable numbers of outer-doublet microtubules in b-d. (B) Drawing of relevant structures in a T. brucei flagellum. Numbers refer to the convention of numbering outer doublets according to their position relative to the central pair and PFR. (C) Graph of frequency of loss of specific outer-doublet microtubules. Bar, 200 nm.