High impact information on dkk1

• This may be due to differential WNT inhibition since dkk1, unlike frzb, inhibits Wnt3a signalling [1].
• Both the requirement of anterior explants for dkk1 function and their ability to respond to dkk1 terminate at late gastrula stage [1].
• Dickkopf1 (dkk1) encodes a secreted WNT inhibitor expressed in Spemann's organizer, which has been implicated in head induction in Xenopus [1].
• Embryos treated with retinoic acid (RA) are not rescued by dkk1 and RA affects the central nervous system (CNS) more posterior than dkk1, suggesting that WNTs and retinoids may act to pattern anterior and posterior CNS, respectively, during gastrulation [1].
• In the neural plate dkk1 is required for anteroposterior and dorsoventral patterning between mes- and telencephalon, where dkk1 promotes anterior and ventral fates [1].

Biological context of dkk1

• Wnts are antagonised by several extracellular inhibitors including the product of the dickkopf1 (dkk1) gene, which was identified in Xenopus embryos and is a member of a multigene family [2].

Anatomical context of dkk1

• Injection of inhibitory antiDkk1 antibodies reveals that dkk1 is not only sufficient but also required for prechordal plate formation but not for notochord formation [1].
• Zebrafish dkk1 is expressed in the dorsal marginal blastoderm and also in the dorsal yolk syncytial layer after mid-blastula transition [3].
• At late neurula stage expression occurs in the prechordal plate adjacent to the prospective forebrain and eyes and in a stripe corresponding to the forming somites. dkk-1 is part of a gene family with at least three family members which is conserved between species [4].

References