Very abundant mRNA, excellent marker of immediate-early response to mesoderm induction. Transcribed from MBT to stage 14.
Expression is induced in animal caps by activin only.
The probe used in B through E probably cross reacts with both Mix.1 and Mix.2. Photo by Richard Harland. B. Section through Mix stained stage 9 embryo. Note both superficial and deep staining. C. D. E. C. Vegetal view of uncleared stage 9 embryo stained with Mix.