Reduction of <i>wnt1</i> expression domain through AP regenerative rescaling is not influenced by <i>bmp4</i> inhibition.

(A) FISH to detect wnt1 expression in regenerating tail fragments at 0, 18, and 96 hours after amputations conducted after 14 days of either control or bmp4 RNAi. Arrows indicate anterior-most wnt1+ cell detected along the dorsal midline for each timepoint and condition. Top panels show control animals undergoing early expansion of the dorsal midline wnt1 domain by 18 hours of regeneration followed by rescaling to reduce the domain to the tip of the animal by 96 hours. Bottom panel shows wnt1 expression dynamics in bmp4 RNAi, in which midline wnt1 expression was anterior expanded at the time of injury (0 hours), remained expanded at 18 hours of regeneration, and then restricted posteriorly by 96 hours, similar to control RNAi conditions. Therefore, BMP pathway modulation is unlikely to be responsible for the normal restriction of wnt1 by 96 hours in regenerating tail fragments. Scale bars represent 150 μm. (B) Graph showing the quantification of the length of the wnt1 domain relative to length of tail fragment. ****p0.05; N ≥ 3 animals. Box plots shows median values (middle bars) and first to third interquartile ranges (boxes); whiskers indicate 1.5× the interquartile ranges and dots are data points from individual animals. (PDF)