Genome wide analysis of Adrenal Gland tissue from Gata6 conditional knockout versus Control Adrenal tissue

Transcription factor GATA6 is expressed in the fetal and adult adrenal cortex and has been implicated in steroidogenesis. To characterize the role of GATA6 in adrenocortical development and function, we generated mice in which Gata6 was conditionally deleted using Cre-LoxP recombination with Sf1-cre. The adrenal glands of adult Gata6 conditional knockout (cKO) mice were small and had a thin cortex with thickened capsule. Cytomegalic changes were evident in the adrenal glands of fetal and adult cKO mice, and chromaffin cells were ectopically located at the periphery of the glands. The secretion of corticosterone in response to exogenous ACTH was blunted in cKO mice. Cells expressing gonadal-like markers, including Gata4, Amhr2, and Tcf21, accumulated in the adrenal capsule and subcapsule of cKO mice, suggesting aberrant adrenocortical progenitor/stem cell differentiation. Gonadectomy triggered the overexpression of sex steroidogenic differentiation markers, such as Lhcgr and Cyp17, in the adrenal glands of male and female cKO mice. Nulliparous female and orchiectomized male cKO mice lacked an adrenal X-zone. Microarray hybridization identified Pik3c2g as a novel X-zone marker that is downregulated in the adrenal glands of nulliparous female Gata6 cKO mice. Our findings offer genetic proof of the longstanding hypothesis that GATA6 regulates the differentiation of steroidogenic progenitors into corticoid-producing cells. 3 replicates from both conditional knockout of Gata6 in the adrenal gland and control adrenal glands from non-knockout mice were compared