|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Development, Vol 125, Issue 16 3123-3132, Copyright © 1998 by Company of Biologists
JOURNAL ARTICLES |
Y Yang, P Guillot, Y Boyd, MF Lyon and AP McMahon
Department of Molecular and Cellular Biology, The Biolabs, Harvard University, Cambridge, MA 02138, USA.
Patterning of the vertebrate limb along the anterior-posterior axis is controlled by the zone of polarizing activity (ZPA) located at the posterior limb margin. One of the vertebrate Hh family members, Shh, has been shown to be able to mediate the function of the ZPA. Several naturally occurring mouse mutations with the phenotype of preaxial polydactyly exhibit ectopic Shh expression at the anterior limb margin. In this study, we report the molecular characterization of a spontaneous mouse mutation, Doublefoot (Dbf). Dbf is a dominant mutation which maps to chromosome 1. Heterozygous and homozygous embryos display a severe polydactyly with 6 to 8 digits on each limb. We show here that Shh is expressed normally in Dbf mutants. In contrast, a second Hh family member, Indian hedgehog (Ihh) which maps close to Dbf, is ectopically expressed in the distal limb bud. Ectopic Ihh expression in the distal and anterior limb bud results in the ectopic activation of several genes associated with anterior-posterior and proximal-distal patterning (Fgf4, Hoxd13, Bmp2). In addition, specific components in the Hedgehog pathway are either ectopically activated (Ptc, Ptc-2, Gli1) or repressed (Gli2). We propose that misexpression of Ihh, and not a novel Smoothened ligand as recently suggested (Hayes et al., 1998), is responsible for the Dbf phenotype. We consider that Ihh has a similar activity to Shh when expressed in the early Shh-responsive limb bud. To determine whether Dbf maps to the Ihh locus, which is also on chromosome 1, we performed an interspecific backcross. These results demonstrate that Dbf and Ihh are genetically separated by approximately 1.3 centimorgans, suggesting that Dbf mutation may cause an exceptionally long-range disruption of Ihh regulation. Although this leads to ectopic activation of Ihh, normal expression of Ihh in the cartilaginous elements is retained.
This article has been cited by other articles:
![]() |
J. Vierkotten, R. Dildrop, T. Peters, B. Wang, and U. Ruther Ftm is a novel basal body protein of cilia involved in Shh signalling Development, July 15, 2007; 134(14): 2569 - 2577. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Lu, G. Minowada, and G. R. Martin Increasing Fgf4 expression in the mouse limb bud causes polysyndactyly and rescues the skeletal defects that result from loss of Fgf8 function Development, January 1, 2006; 133(1): 33 - 42. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Liu, B. Wang, and L. A. Niswander Mouse intraflagellar transport proteins regulate both the activator and repressor functions of Gli transcription factors Development, July 1, 2005; 132(13): 3103 - 3111. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. L. Wise and D. D. Pravtcheva Oligosyndactylism Mice Have an Inversion of Chromosome 8 Genetics, December 1, 2004; 168(4): 2099 - 2112. [Abstract] [Full Text] [PDF] |
||||
![]() |
H Thiele, C McCann, S van't Padje, G C Schwabe, H C Hennies, G Camera, J Opitz, R Laxova, S Mundlos, and P Nurnberg Acropectorovertebral dysgenesis (F syndrome) maps to chromosome 2q36 J. Med. Genet., March 1, 2004; 41(3): 213 - 218. [Full Text] [PDF] |
||||
![]() |
O. Krebs, C. M. Schreiner, W. J. Scott Jr, S. M. Bell, D. J. Robbins, J. A. Goetz, H. Alt, N. Hawes, E. Wolf, and J. Favor Replicated anterior zeugopod (raz): a polydactylous mouse mutant with lowered Shh signaling in the limb bud Development, December 15, 2003; 130(24): 6037 - 6047. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Topol, X. Jiang, H. Choi, L. Garrett-Beal, P. J. Carolan, and Y. Yang Wnt-5a inhibits the canonical Wnt pathway by promoting GSK-3-independent {beta}-catenin degradation J. Cell Biol., September 1, 2003; 162(5): 899 - 908. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. G. McFadden, J. McAnally, J. A. Richardson, J. Charite, and E. N. Olson Misexpression of dHAND induces ectopic digits in the developing limb bud in the absence of direct DNA binding Development, January 7, 2002; 129(13): 3077 - 3088. [Abstract] [Full Text] [PDF] |
||||
![]() |
J Charite, D. McFadden, and E. Olson The bHLH transcription factor dHAND controls Sonic hedgehog expression and establishment of the zone of polarizing activity during limb development Development, January 6, 2000; 127(11): 2461 - 2470. [Abstract] [PDF] |
||||
![]() |
C Tribioli and T Lufkin The murine Bapx1 homeobox gene plays a critical role in embryonic development of the axial skeleton and spleen Development, January 12, 1999; 126(24): 5699 - 5711. [Abstract] [PDF] |
||||
![]() |
K. Lewis, G Drossopoulou, I. Paton, D. Morrice, K. Robertson, D. Burt, P. Ingham, and C Tickle Expression of ptc and gli genes in talpid3 suggests bifurcation in Shh pathway Development, January 6, 1999; 126(11): 2397 - 2407. [Abstract] [PDF] |
||||