Opposing effects on TSC-22 expression by BMP and receptor tyrosine kinase signals in the developing feather tract.
TSC-22 (transforming growth factor-beta-stimulated clone 22) belongs to a family of leucine zipper transcription factors that includes sequences from invertebrates and vertebrates. The single Drosophila family member, encoded by the bunched gene, serves to integrate opposing bone morphogenic protein (BMP) and epidermal growth factor (EGF) signals during oogenesis. Similarly, mammalian TSC-22 expression is regulated by several families of secreted signaling molecules in cultured cells. Here, we show that chick TSC-22 is dynamically expressed in the condensing feather bud, as well as in many tissues of the chick embryo. BMP-2/4, previously shown to inhibit bud development, repress TSC-22 expression during feather bud formation in vivo. Noggin, a BMP antagonist, promotes TSC-22 expression. EGF, TGF-alpha, and fibroblast growth factor all promote both feather bud development and TSC-22 expression; each can promote ectopic feather buds that are regularly spaced between existing feather buds. Thus, TSC-22 is a candidate to integrate small imbalances in receptor tyrosine kinase and BMP signaling during feather tract development to generate stable and reproducible morphogenetic responses.
Dohrmann
Cord E
CE
Cutaneous Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Charlestown, Massachusetts 02129, USA.
Noramly
Selina
S
Raftery
Laurel A
LA
Morgan
Bruce A
BA
D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000494:pharmacology; D002352:Carrier Proteins; D002642:Chick Embryo; D046508:Culture Techniques; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005241:Feathers / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000494:pharmacology; D017403:In Situ Hybridization; D016350:Leucine Zippers; D051379:Mice; D011506:Proteins / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D016211:Transforming Growth Factor alpha / Q000494:pharmacology; D000099176:Noggin Protein
D019485:Bone Morphogenetic Proteins; D002352:Carrier Proteins; D004815:Epidermal Growth Factor; D005346:Fibroblast Growth Factors; D011506:Proteins; D020794:Receptor Protein-Tyrosine Kinases; D012097:Repressor Proteins; D016211:Transforming Growth Factor alpha; D000099176:Noggin Protein; C490983:Tgfb1i4 protein, mouse