The role of MAPK signaling in patterning and establishing axial symmetry in the gastropod Haliotis asinina

摘要: Gastropods are members of the Spiralia, a diverse group invertebrates that share common early developmental program, which includes spiral cleavage and larval trochophore stage. The program results in division embryo into four quadrants. Specification dorsal (D) quadrant is intimately linked with body plan organization equally cleaving gastropods occurs when one vegetal macromeres makes contact overlying micromeres receives an inductive signal activates MAPK signaling cascade. Following induction 3D macromere, begins to gastrulate assumes bilateral pattern. Here we inhibit activation U0126 examine its effect on formation patterning trochophore, using suite territory-specific markers. head (pretrochal) region appears maintain quadri-radial symmetry U0126-treated embryos, supporting role for establishing dorsoventral polarity this region. Posterior (posttrochal) structures – musculature, shell foot fail develop inhibited trochophores. Inhibition specification by alternative method monensin treatment yields similar abnormal However, genes normally expressed ectodermal (shell foot) detected U0126- monensin-perturbed larvae patterns suggest has latent manifested even absence D specification.