Fig 6G. [doi:10.1242/dev.00946] Copyright: This image is from Zakin L; De Robertis EM, "Inactivation of mouse Twisted gastrulation reveals its role in promoting Bmp4 activity during forebrain development" Development 2004;131:413-424 and is displayed with the permission of The Company of Biologist Limited who owns the Copyright. [PMID:14681194]