The neural tube is patterned along dorsal/ventral axis and anterior/posterior axis. The key players in the ventral patterning of neural tube are Sonic hedgehog (Shh) and retinoic acid (RA). They are secreted by the notochord and later by floor plate.
High Shh specifies motor neurons in the ventral neural tube and ventral interneurons. Wnt and bone morphogenic proteins (BMPs) on the other hand are secreted by the roof plate, and specify dorsal interneurons by antagonizing ventralizing activity of Shh.
Researchers found that Wnt signaling is also active in the ventral neural tube.
The evidence above would predict which of the following?
Select ALL that apply.