BMP suppresses WNT to integrate patterning of orthogonal body axes in adult planarians.

Systems that coordinate long-range communication across axes are likely critical for enabling tissue restoration in regenerative animals. While individual axis pathways have been identified, there is not yet an understanding of how signal integration allows repatterning across 3-dimensions. Here, we report an unanticipated linkage between anteroposterior, dorsoventral, and mediolateral systems in planarians through BMP signaling. We find that dorsally expressed BMP restricts posterior and lateral identity by suppressing distinct Wnt signals in adult planarians. These results demonstrate that orthogonal axis information is not fully independent and suggest a potentially ancient role of integrated axis patterning in generating stable 3-dimensional adult forms.