Ultrastructural localization of TcKAPs by transmission electron microscopy. A-D-G-J: ultrastructural analyses of the kinetoplast in the different developmental stages of T. cruzi. The kinetoplast of intermediate forms (G) is larger than the bar-shaped kinetoplast of epimastigotes (A) and amastigotes (D). The trypomastigotes (J) present a more relaxed kDNA organization, contained within a rounded kinetoplast. TcKAP4 (B-E-H-K) was distributed throughout the kinetoplast DNA network in epimatigotes (B) and amastigotes (E-arrow). In intermediate forms (H) and in trypomastigotes (K), TcKAP4 was distributed mainly at the periphery of the kDNA. The same result was observed for TcKAP6 (C-F-I-L). A homogenous distribution for all kinetoplast was observed in epimastigotes (C) and amastigotes (F-arrows), while a more peripherical distribution was seen in intermediate forms (I) and trypomastigotes (L). Bars = 0.25 μm. k = kinetoplast, n = nucleus, bb = basal body.