What are the main dorsalizing and neuralizing factors in Xenopus? What are the main inducing factors controlling anteroposterior pattern? Solution Ques-12: Answer: The Xenopus dorsalizing factors such as “noggin” are responsible for formation of Spermann organizer in Xenopus embryos finally promote “dorsal & ventral cell fate inside the mesoderm”. The other cereberus like –neutralizing factors are going tot promote formation of neural development via Wnt signaling.