Asymmetric expression of Notch/Delta/Serrate is associated with the anterior-posterior axis of feather buds.
We studied the roles of Notch, Delta, and Serrate in vertebrate epithelial appendage morphogenesis using feather as a model and found the following. (1) C-Notch-1, C-Delta-1, and C-Serrate-1 are not expressed at the early placode stage and are therefore not involved in the determination of bud versus interbud compartments. (2) From symmetric short buds to asymmetric long buds, C-Delta-1 and C-Serrate-1 are expressed in the posterior bud mesenchyme in a nested fashion, while C-Notch-1 is expressed as a stripe perpendicular to the anterior-posterior (A-P) axis and positioned posterior to the midpoint. (3) Epithelial-mesenchymal recombination with rotation led to the disappearance of these genes followed by their reappearance with new positions appearing to predict their new morphological orientation. (4) Conditions leading to branched buds (e.g., recombination of later buds) show polarized staining patterns before branching occurs. (5) Conditions leading to symmetrical round buds (e.g., treated with the protein kinase A agonist forskolin) suppress expression of all three genes. These results lead us to hypothesize that Notch, Delta, and Serrate are involved in establishing the A-P asymmetry of feather buds.
Chen
C W
CW
School of Medicine, University of Southern California, HMR 204, 2011 Zonal Avenue, Los Angeles, California 90033, USA.
Jung
H S
HS
Jiang
T X
TX
Chuong
C M
CM
D000818:Animals; D002135:Calcium-Binding Proteins; D002642:Chick Embryo; D005576:Colforsin / Q000494:pharmacology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000819:agonists; D005241:Feathers / Q000196:embryology* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D009024:Morphogenesis; D009924:Organ Culture Techniques; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D000072099:Serrate-Jagged Proteins; D015398:Signal Transduction; D012867:Skin / Q000196:embryology* / Q000378:metabolism; D014157:Transcription Factors
D002135:Calcium-Binding Proteins; D036341:Intercellular Signaling Peptides and Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D000072099:Serrate-Jagged Proteins; D014157:Transcription Factors; C064045:delta protein; D005576:Colforsin; D017868:Cyclic AMP-Dependent Protein Kinases