Cloning and expression of the Wnt antagonists Sfrp-2 and Frzb during chick development.
The Wnt genes are known to play fundamental roles during patterning and development of a number of embryonic structures. Receptors for Wnts are members of the Frizzled family of proteins containing a cysteine-rich domain (CRD) that binds the Wnt protein. Recently several secreted frizzled-related proteins (Sfrps) that also contain a CRD have been identified and some of these can both bind and antagonise Wnt proteins. In this paper we report the expression patterns of the chick homologues of Frzb, a known Wnt antagonist, and Sfrp-2. Both genes are expressed in areas where Wnts are known to play a role in development, including the neural tube, myotome, cartilage, and sites of epithelial-mesenchymal interactions. Initially, Sfrp-2 and Frzb are expressed in overlapping areas in the neural plate and neural tube, whereas later, they have distinct patterns. In particular Sfrp-2 is associated with myogenesis while Frzb is associated with chondrogenesis, suggesting that they play different roles during development. Finally, we have used the early Xenopus embryo as an in vivo assay to show that Sfrp-2, like Frzb, is a Wnt antagonist. These results suggest that Sfrp-2 and Frzb may function in the developing embryo by modulating Wnt signalling.
Ladher
R K
RK
Department of Craniofacial Development, Guy's, King's and St. Thomas' School of Dentistry, Guy's Tower, Floor 27, Guy's Hospital, London, SE1 9RT, United Kingdom. rladher@hgmp.mrc.ac.uk
Church
V L
VL
Allen
S
S
Robson
L
L
Abdelfattah
A
A
Brown
N A
NA
Hattersley
G
G
Rosen
V
V
Luyten
F P
FP
Dale
L
L
Francis-West
P H
PH
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002642:Chick Embryo; D003001:Cloning, Molecular; D017931:DNA Primers; D047108:Embryonic Development; D005136:Eye Proteins / Q000235:genetics*; D006023:Glycoproteins; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors; D017386:Sequence Homology, Amino Acid; D051153:Wnt Proteins; D014981:Xenopus; D029961:Zebrafish Proteins; D000099274:Frizzled-Related Proteins
D017931:DNA Primers; D005136:Eye Proteins; D006023:Glycoproteins; D047908:Intracellular Signaling Peptides and Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D051153:Wnt Proteins; D029961:Zebrafish Proteins; D000099274:Frizzled-Related Proteins