Cerberus-like is a secreted BMP and nodal antagonist not essential for mouse development

Mouse cerberus-like (cer-I) is a member of the Cerberus/Dan family of secre ted factors. As other members of this family of proteins, Cer-l functions i n the extracellular space, inhibiting signaling molecules. Here we show tha t the neural-inducing and mesoderm-inhibiting activities of Cer-l result fr om specific binding to BMP and Nodal molecules, respectively. These propert ies resemble the ones from the related factor Xenopus Cerberus, However, Xe nopus Cerberus in addition to BMP4 and Nodal also binds to and inhibits Wnt proteins, We show that Cer-l does not directly inhibit Wnt signals. A null allele of the mouse Cer-l gene was generated by targeted inactivation in E S cells. Homozygous embryos show no anterior patterning defects, are born a live, and are fertile, Since mouse Cer-I and Xenopus Cerberus differ in bio chemical activities, we propose the existence of additional members of this family of inhibitors, which may compensate for the loss of cer-I, genesis 26: 265-270, 2000, (C) 2000 Wiley-Liss, Inc.