Fig. 3. Dynamics of ER replication and segregation. Parasites expressing IMC1-YFP (green) and P30_L-mRFP-HDEL (red) were examined through the cell cycle using time-lapse microscopy. During interphase (top row), the nucleus is surrounded by the endoplasmic reticulum (ER), from which branches extend both apically and basally. The perinuclear ER expands with the nucleus, and ramifies to form extensive branches coincident with daughter scaffold formation (t=0'). Emanations from the ER associate with the developing IMC (arrowheads; +40'), enter into the developing daughters along with the nucleus (+70', +90'), and continue to segregate (+130') until the emergence of daughter parasites from the mother, leaving a small amount of material behind in the residual body (+170'). Scale bar: 5 µm.