Merging nodes can be viewed as an abridging of the translation process. Structures of type (a), where ACT, REP, and are proteins and is some mRNA ( and are products of the same gene), are seen throughout Figure 1(a). When and are products of the patched or engrailed genes we propose that such structures can be replaced by a structure of type (b), where here is the result of having merged the and nodes of (a).