Fig 1.

Overall architecture of the ventral disc highlighting the overlap zone. (A) A schematic view of the Giardia cytoskeleton shows the median body (mb), the ventral disc MT (vdMT) and supernumerary MT (snMT) spiral arrays, the overlap zone (oz) of the ventral disc MTs, the lateral crest (lc), the basal bodies (bb), and the four flagellar pairs (ventral flagella [vfl], caudal flagella [cfl], posteriolateral flagella [pfl], and anterior flagella [afl]). mg, marginal groove; ba, bare area. (B) A scanning electron micrograph of the detergent-extracted cytoskeleton highlights the overlap zone, the cellular regions underlying the bare area, the marginal groove, and the lateral crest as viewed from the ventral side. (C) Negative staining of the detergent-extracted cytoskeleton shows the cytological positions of the anterior and ventral flagella relative to the ventral disc as seen from the dorsal side and highlights hallmark features, such as the regular and evenly spaced microtubules of the ventral disc overlapping one-quarter turn in the overlap zone.