Mj. Han et Ws. Kim, THE EFFECTS OF RETINOIC ACID ON THE EPIDERMAL GROWTH-FACTOR RECEPTOR GENE-EXPRESSION IN THE DEVELOPING CHICK WING BUD, Molecules and cells, 6(3), 1996, pp. 252-258
The epidermal growth factor receptor (EGFR), a c-erbB protooncogene pr
oduct, is known to control cell growth and cell differentiation. EGFR
gene expression is also known to be regulated by retinoic acid (RA). I
n the present study, the temporal and spatial patterns of EGFR gene ex
pression in normal and RA-treated chick wing buds have been examined b
y in situ hybridization. In normal wing bud, a strong signal of EGFR g
ene expression was noted at the anterior and distal areas of epidermal
. and subepidermal tissues during Hamburger-Hamilton stages 18-26, whi
le the signal was weak in the posterior area. In the RA-treated wing b
ud, at 1 and 2 days after treatment (stages 24 and 26, respectively),
the area of EGFR gene expression expanded to the more posterior region
, while the expression of EGFR was suppressed in the RA-applied area i
mplying that EGFR gene expression was suppressed by RA treatment in th
e developing Chick wing bud. In the subepidermal area, EGFR gene was c
ontinuously expressed until stage 30. These results suggest that EGFR
might be involved in the tissue interactions for the patterning of dev
eloping chick wing bud.