CSAR1 exhibits dynamic localization through the Toxoplasma cell cycle. (A) Late in mitosis (monitored by GFP-tubulin signal; green), in 68% of vacuoles examined, CSAR1^3xHA signal (magenta) is bright and confined to the maternal cytosol (see Fig. S3, below). In 32% of these vacuoles, CSAR1^3xHA has begun to concentrate at the residual body (lower panel; yellow arrowhead). (B and C) As the vacuoles with CSAR1-residual body signal tend to contain larger daughter buds on average (B), we assume this relocalization of CSAR1 is occurring in parasites that have progressed further in mitosis, and which we therefore refer to in C as “Very late mitosis.” P value is from 2-tailed unpaired Student’s t test. Normality tested by Shapiro-Wilk test. (C) Gallery of representative images of CSAR1^3xHA localization during cell cycle in parasites untreated with IAA during the second division cycle (2 → 4 parasites).