The relative contributions of nuclear flow and expression flow to pattern flow. Orthographic projections of the locations of ftz, hb, eve, gt, and Kr stripe borders in early stage 5 (blue lines) and late stage 5 (red lines) embryos. The stripe locations are taken from the earliest and latest applicable embryo cohort (5:4-8% to 5:75-100% for ftz and eve; 5:0-3% to 5:51-75% for hb, gt and Kr). The axes are labeled as in Figure 4. Our model of nuclear flow was used to predict the location of stripe borders in late embryos in the absence of changing expression levels (dotted black lines). The left panels compare the measured locations of the early and late stripe borders, and thus show the pattern flow. The center panels show the movement predicted to be due only to nuclear flow. The right panels show the residual movement (expression flow) that can be attributed to zones of up/down-regulation along stripe boundaries.
Keränen et al. Genome Biology 2006 7:R124 doi:10.1186/gb-2006-7-12-r124