Variegated expression of a mouse steroid 21-hydroxylase/beta- galactosidase transgene suggests centripetal migration of adrenocortical cells

• Published in: Molecular endocrinology (Baltimore, Md.) Vol. 10; no. 5; pp. 585 - 598
• Main Authors: Morley, S D, Viard, I, Chung, B C, Ikeda, Y, Parker, K L, Mullins, J J
• Format: Journal Article
• Language: English
• Published: United States 01.05.1996
• Subjects: Adrenal Cortex - cytology; Adrenal Cortex - enzymology; Adrenal Cortex Neoplasms - enzymology; Adrenal Glands - embryology; Adrenal Glands - enzymology; Animals; Base Sequence; beta-Galactosidase - genetics; Cell Movement; Female; Gene Expression; Genes, Reporter; Male; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Molecular Sequence Data; Pedigree; Promoter Regions, Genetic; RNA, Messenger - analysis; Steroid 21-Hydroxylase - genetics; Tissue Distribution
• ISSN: 0888-8809
• DOI: 10.1210/me.10.5.585

5'-Flanking sequences (6.4 kb) of the mouse steroid 21-hyrodxylase (21-OHase) A gene linked to a LacZ reporter gene directed appropriate cell-specific expression in cultured Y1 adrenocortical tumor cells and in the adrenal cortex of transgenic mice. The transgene expression initiated at the same stage of adrenal development as the endogenous 21-OHase gene (embryonic day 11.5). Although the endogenous 21-OHase gene is expressed throughout the adrenal cortex, the 21-OHase/beta-gal transgene showed a strikingly variegated pattern of adrenocortical expression in all 10 transgene-expressing mouse lines examined. This presents as radial stripes of beta-gal staining transcending the classical zonal structure of the adrenal cortex but paralleling the columnar arrangement of cells of the zona fasciculata on the centripetal organization of the adrenocortical blood supply. To the extent that the variegated pattern of 21-OHase/beta-gal transgene expression depicts adrenocortical cell lineage, these results suggest that all cells within an individual stripe have a common clonal origin; the radial pattern of clonally derived cells argues that cellular migration maintains the adult adrenocortical cell population. Adrenal glands of developing embryos also exhibited a variegated pattern of 21-OHase/beta-gal transgene expression. However, this presented as islands of beta-gal reporter staining within the developing gland, suggesting that the rapid embryonic adrenal growth phase, which precedes the establishment of the classic adrenocortical zonal structure, may be governed by cellular mechanisms distinct from those responsible for maintenance of the adult adrenocortical cell population.