Medaka spalt acts as a target gene of hedgehog signaling.
In vertebrates, pattern formation in the eye, central nervous system, somites, and limb depends on hedgehog activity, but a general target gene controlled by hedgehog in all these signaling centers has remained largely elusive. The medaka fish gene spalt encodes a zinc-finger transcription factor, which is expressed in all known hedgehog signaling centers of the embryo and in the organizer region at the midbrain-hindbrain boundary. We show that the spalt expression domains expand in response to ectopic hedgehog activity and narrow in the presence of protein kinase A activity, an antagonist of hedgehog signaling, indicating that spalt is a hedgehog target gene. Our results also suggest a signaling mechanism for anterior-posterior patterning of the vertebrate brain that controls spalt expression at the midbrain-hindbrain boundary in a protein kinase A dependent manner likely to involve an unknown member of the hedgehog family.
Koster
R
R
SFB 271 Junior Group, c/o Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
Stick
R
R
Loosli
F
F
Wittbrodt
J
J
D000595:Amino Acid Sequence; D000818:Animals; D019521:Body Patterning / Q000235:genetics*; D002490:Central Nervous System / Q000196:embryology; D003001:Cloning, Molecular; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D004268:DNA-Binding Proteins / Q000235:genetics; D029721:Drosophila Proteins; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D005796:Genes / Q000235:genetics; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000235:genetics*; D008636:Mesencephalon / Q000196:embryology; D008969:Molecular Sequence Data; D009474:Neurons / Q000737:chemistry; D009990:Oryzias; D051762:PAX2 Transcription Factor; D011506:Proteins / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D012249:Rhombencephalon / Q000196:embryology; D017422:Sequence Analysis, DNA; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics*
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; D051762:PAX2 Transcription Factor; D011506:Proteins; D012333:RNA, Messenger; D015534:Trans-Activators; D014157:Transcription Factors; C085793:salm protein, Drosophila; D017868:Cyclic AMP-Dependent Protein Kinases