Phylogenetic conservation of a limb-specific, cis-acting regulator of Sonic hedgehog ( Shh).
Polarized expression of the Sonic hedgehog ( Shh) gene in the posterior mesenchyme is essential for pattern formation in the appendages of higher vertebrates, from teleost fins to tetrapod limb buds. We report on a sequence in intron 5 of the Lmbr1 gene, which resides approximately 1 Mb from the Shh coding region in the mouse genome and is highly conserved among teleost fishes and throughout the tetrapod lineage. Positional cloning revealed that two mouse mutations, Hx and M100081, characterized by mirror-image digit duplication and ectopic anterior Shh expression, have base substitutions in this sequence. Absence of the conserved sequence in limbless reptiles and amphibians and a cis- trans test using the Hx and Shh KO alleles suggest that the sequence is a cis-acting regulator that controls the polarized expression of Shh.
Sagai
Tomoko
T
Mammalian Genetics Laboratory, National Institute of Genetics, Yata-1111, Mishima, Shizuoka-ken 411-8540, Japan.
Masuya
Hiroshi
H
Tamura
Masaru
M
Shimizu
Kunihiko
K
Yada
Yukari
Y
Wakana
Shigeharu
S
Gondo
Yoichi
Y
Noda
Tetsuo
T
Shiroishi
Toshihiko
T
D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D003433:Crosses, Genetic; D018507:Gene Expression Regulation, Developmental; D005809:Genes, Regulator / Q000235:genetics*; D005819:Genetic Markers; D016678:Genome; D053823:Hedgehog Proteins; D018878:Limb Buds / Q000196:embryology*; D008565:Membrane Proteins / Q000235:genetics; D051379:Mice / Q000235:genetics*; D008810:Mice, Inbred C57BL; D015778:Minor Histocompatibility Antigens / Q000235:genetics; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D017689:Polydactyly / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism
D005819:Genetic Markers; C083796:HX antigen; D053823:Hedgehog Proteins; C417920:Lmbr1 protein, mouse; D008565:Membrane Proteins; D015778:Minor Histocompatibility Antigens; D015534:Trans-Activators