|
six1/six4 genes are required for full MMP specification. RNA in situ hybridization of Δsix1a;4a mutants (left column) or Δsix1a;4a;Δsix1b;4b mutants (right column) fixed at (A-J) 24 hpf or (K-N) 36 hpf. Arrowheads point to MMPs and MMP-like cells. For all MMP markers tested, Δsix1a;4a-/- embryos show wild-type expression. Compared to controls, Δsix1a;4a;Δsix1b;4b mutants show normal (A, B) lbx2, (C, D) pax3a, and (E, F) pax3b gene expression at 24 hpf (A-F). However, Δsix1a;4a;Δsix1b;4b mutants lack lbx1a and met gene expression in MMPs at (G-J) 24 hpf and (K-N) 36 hpf. At 24 hpf, arrowhead color is assigned based on somite count: arrowheads pointing to somite 2 are red, somite 4 is gray, and somite 5 is light blue. At 36 hpf, arrowhead color is assigned based on stream shape and corresponds to that described in Figures 1 and S1. Expression of met in lateral line primordia is indicated by white arrows.
|
