Weinziger, Ruth; Salgado, Luis M.; David, Charles N.; Bosch, Thomas C. G.
Ks1, an epithelial cell-specific gene, responds to early signals of head formation in Hydra.
In: Development, Vol. 120: pp. 2511-2517
As a molecular marker for head specification in
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 diacylglycerol second
messenger system is involved in head-specific differentiation.