Fig. 7.

Maternal IMC is recycled into developing daughters after their emergence. (A) The entire IMC of one parasite was photobleached (yellow), whereas that of its sister was not (providing an internal control). Time-lapse imaging reveals comparable fluorescence of the daughter IMCs elongating within bleached versus unbleached mothers but, after emergence (308 min), daughters maturing from the unbleached mother are brighter than those from the bleached mother. During the maturation phase, cytoplasmic fluorescence is evident in daughters from the unbleached control parent (filled arrowhead) but not the bleached parent (open arrowhead). (B) Quantification of IMC fluorescence in daughters from unbleached control parasites (solid symbols) versus bleached parasites (open symbols). Panels are based on independent experiments, corresponding to images in Fig. 7A (left; see also supplementary material Movie 4) and Fig. 3A (right; supplementary material Movie 3). Color coding indicates IMC initiation (blue), elongation (aqua), emergence (magenta) and maturation (red). Note that fluorescence is comparable in daughters emerging from bleached versus unbleached mothers through the elongation stage but diverges after emergence, as daughters maturing from unbleached controls remain bright, whereas those from bleached mothers continue to grow without accumulating additional fluorescence. Transient cytoplasmic fluorescence is observed in daughters maturing from unbleached controls (gray) but not bleached mothers (yellow). Filled and open diamonds indicate the fluorescence of parental parasites before bleaching. (C) Cartoon showing de novo synthesis of the IMC during elongation and salvage of the maternal IMC during maturation. Scale bar: 5 µm.