Figure 8. The maintenance and regeneration of adult maxillary barbel taste buds are unaffected by 14 days of heat shock in the dn-fgfr1 line.

A) Representative in-tank temperature logs for the 14-day taste bud regeneration experiment. The heat-shock trace for each day is superimposed on the same temperature and time scale. The average peak temperature is shown in red (37.7°C). B) Gross morphology of dn-fgfr1 caudal fins at the 14-day endpoint. Caudal fin outgrowth was abolished; in some individuals, the fin margin shrank (arrows, right). All heat-shocked wild type siblings regenerated caudal fins normally (not shown). C) Heat-shock treatment reduced maxillary barbel regeneration approximately 50% compared to wild type controls (p < 0.0001) D) Gross morphology of wild type and dn-fgfr1 barbels at the 14 day endpoint. Black dotted lines indicate amputation planes. L = left, amputated barbel; R = right, unamputated barbel. E–L) To assay taste bud regeneration, all of the heat-shocked wild type and dn-fgfr1 barbels (amputated and unamputated) were stained for calretinin immunoreactivity; DAPI was used to mark nuclei. There was no difference in either the arrangement (E–H) or fine structure of calretinin-positive gustatory cells in the barbel epithelium (I–L) among any of the treatment groups.