Ks1, an epithelial cell-specific gene, responds to early signals of head formation in Hydra.
As a molecular marker for head specification in Hydra, we have cloned an epithelial cell-specific gene which responds to early signals of head formation. The gene, designated ks1, encodes a 217-amino acid protein lacking significant sequence similarity to any known protein. KS1 contains a N-terminal signal sequence and is rich in charged residues which are clustered in several domains. ks1 is expressed in tentacle-specific epithelial cells (battery cells) as well as in a small fraction of ectodermal epithelial cells in the gastric region subjacent to the tentacles. Treatment with the protein kinase C activator 12-O-tetradecanoylphorbol-13-acetate (TPA) causes a rapid increase in the level of ks1 mRNA in head-specific epithelial cells and also induces ectopic ks1 expression in cells of the gastric region. Sequence elements in the 5'-flanking region of ks1 that are related to TPA-responsive elements may mediate the TPA inducibility of ks1 expression. The pattern of expression of ks1 suggests that a ligand-activated diacyglycerol second messenger system is involved in head-specific differentiation.
Zoological Institute, University Munich, FRG.
R
R
Weinziger
L M
LM
Salgado
C N
CN
David
T C
TC
Bosch
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004847:Epithelial Cells; D015870:Gene Expression / Q000187:drug effects; D005786:Gene Expression Regulation; D006257:Head / Q000502:physiology*; D006829:Hydra / Q000235:genetics* / Q000502:physiology; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D011493:Protein Kinase C / Q000502:physiology; D011506:Proteins / Q000235:genetics*; D012038:Regeneration / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D036341:Intercellular Signaling Peptides and Proteins; C090508:KSI protein, Hydra vulgaris; D011506:Proteins; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate