Characterization of Glucocorticoid-Induced Changes in Gene Expression in the Embryonic Pituitary Gland.. Gallus gallus

We have previously shown that corticosterone (CORT) can induce premature differentiation of somatotrophs in the chicken embryo. CORT induction of GH mRNA is indirect, in that protein synthesis inhibition blocks its inducing effect. In this study, we used a custom chicken microarray to analyze global gene expression in the embryonic pituitary gland and to identify potential direct targets of CORT that may regulate its induction of somatotroph differentiation. Our microarray analysis revealed 25 direct early targets of CORT. Keywords: Duration of corticosterone treatment on gene expression levels Overall design: Four biological replicates each of the twelve treatment groups from cultured chicken embryonic day 11 pituitary cells amplified antisense RNA were analyzed using DEL-MAR 14K Integrated Systems Microarray in a reference design. Each experimental sample was labeled with Cy3 and hybridized with an aliquot of the Cy5 reference pool, which was generated from all forty-eight RNA samples.