CKIδ is required for centrosome translocation to the IS. (A) Still images from time-lapse videos showing conjugate formation between Jurkat cells transfected with GFP-centrin1 (green) and SEE-pulsed Raji cells (blue). Control (EV; top; Videos 1 and 2) and CKIδ-depleted Jurkat cells (shdelta; bottom; Videos 3 and 4) are shown. Bar, 10 µm. The percentages next to panels indicate the frequency of the particular phenotype. The plots below depict the distance between the centrosome and the IS as a function of time; time 0 is when the conjugate forms. Tracks are symbol- and color-matched to individual cells. The shdelta cell (orange) polarizes its centrosome with a delay. (B) Summary of the time-lapse data collected. (C) Distribution of the time required for centrosome polarization to the IS in control (EV) and CKIδ-depleted (shdelta) cells. Median values are marked by horizontal lines.