title: Local Dkk1 crosstalk from breeding ornaments impedes regeneration of injured male zebrafish fins.
abstract: Precise spatiotemporal regulation of signaling activators and inhibitors can help limit developmental crosstalk between neighboring tissues during morphogenesis, homeostasis, and regeneration. Here, we find that the secreted Wnt inhibitor Dkk1b is abundantly produced by dense regions of androgen-regulated epidermal tubercles (ETs) on the surfaces of adult male zebrafish pectoral fins. High-speed videos and amputation experiments reveal that pectoral fins and their ETs are used for male spawning. Formation and vigorous turnover of ETs involve Dkk1b induction and maintenance, whereas Dkk1b is typically restricted from the regeneration blastema after an amputation injury. When amputation occurs through a region containing ETs, a Dkk1b-enriched wound epidermis forms and blastema formation is disrupted, compromising regeneration. Thus, homeostatic signaling by key breeding ornaments can interfere with injury-activated tissue regeneration. Our findings help explain sexually dimorphic fin regeneration in zebrafish and have implications for how regenerative potential might decline as development progresses or during species evolution.
authors.affiliation: Department of Cell Biology and Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Junsu
authors.initials: J
authors.lastname: Kang
authors.forename: Gregory
authors.initials: G
authors.lastname: Nachtrab
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Poss
mesh_terms: D000728:Androgens / Q000494:pharmacology; D058500:Animal Fins / Q000293:injuries / Q000502:physiology*; D000818:Animals; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006706:Homeostasis; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D062326:Re-Epithelialization; D012727:Sex Characteristics; D012737:Sex Factors; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism; D060449:Wnt Signaling Pathway; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000728:Androgens; D036341:Intercellular Signaling Peptides and Proteins; D051153:Wnt Proteins; D029961:Zebrafish Proteins; C501128:dkk1b protein, zebrafish