Identical origin of adrenal cortex and gonad revealed by expression profiles of Ad4BP/SF-1.
BACKGROUND
Ad4BP/SF-1 was originally identified as a steroidogenic tissue-specific transcription factor. Recent gene disruption studies with the mammalian Ftz-F1 gene encoding Ad4BP/SF-1 clearly revealed the essential function of the factor for adrenal and gonadal differentiation.


RESULTS
In this study, we examined the early development of these tissues using Ad4BP/SF-1 as the marker. In rat foetuses of 11.5 days post-coitum (d.p.c.), a cell population designated adrenogenital primordium was firstly observed on symmetrical lines extending from the dorsal aorta to the dorsal coelomic epithelia of the primitive urogenital ridges. From 12.5 d.p.c., the rostral half of the adreno-genital primordium started to separate into two distinct cell populations. Judging from the distribution of primordial germ cells, the cell population on the dorsal aortal side is a primordium for the adrenal cortex whereas that on the coelomic epithelial side is for the gonads. At 13.5 d.p.c., these two primordia have separated completely.


CONCLUSIONS
These observations clearly identified a novel adreno-genital primordium from which both the adrenal cortex and the gonads originate. An RT-PCR study conducted to detect adrenal- and gonad-specific mRNAs supported the above observations.
Hatano
O
O
Department of Anatomy, Nara Medical University, Japan.
Takakusu
A
A
Nomura
M
M
Morohashi
K
K
D000302:Adrenal Cortex / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D000818:Animals; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D051717:Fushi Tarazu Transcription Factors; D018507:Gene Expression Regulation, Developmental; D005819:Genetic Markers; D006066:Gonads / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D018398:Homeodomain Proteins; D007150:Immunohistochemistry; D008297:Male; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018160:Receptors, Cytoplasmic and Nuclear; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D054339:Steroidogenic Factor 1; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D017931:DNA Primers; D004268:DNA-Binding Proteins; D051717:Fushi Tarazu Transcription Factors; D005819:Genetic Markers; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D054339:Steroidogenic Factor 1; D014157:Transcription Factors