Expression of IGF-II and H19 mRNA in the neonatal rat during normal maturation and after dexamethasone administration.
In this study, the expression of IGF-II and H19 was examined in the liver, skeletal muscle and choroid plexus of the neonatal rat during normal maturation and after the administration of dexamethasone. If the two genes share common regulatory elements as postulated by an enhancer competition system, their patterns of expression should remain similar throughout maturation and after treatment with dexamethasone. In the liver, down-regulation of IGF-II and H19 during maturation and after dexamethasone administration was shown. This is consistent with the hypothesis that IGF-II and H19 are regulated by common enhancers. In the secretory cells of the choroid plexus, where expression of IGF-II is known to be biallelic, IGF-II was expressed in both untreated and dexamethasone-treated animals, regardless of age, whereas H19 expression was not detectable. This is consistent with the postulate that only one gene from each allele can be engaged by the enhancers. In skeletal muscle, H19 continues to be expressed in the adult after IGF-II is switched off suggesting that IGF-II can also be regulated independently of H19.
Senior
P V
PV
Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria, Australia.
Tucci
J
J
Blythe
N L
NL
Beck
F
F
D000818:Animals; D000831:Animals, Newborn; D002831:Choroid Plexus / Q000166:cytology / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D008099:Liver / Q000378:metabolism; D009124:Muscle Proteins / Q000235:genetics*; D018482:Muscle, Skeletal / Q000378:metabolism; D062085:RNA, Long Noncoding; D012333:RNA, Messenger / Q000235:genetics*; D022661:RNA, Untranslated; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar
C094335:H19 long non-coding RNA; D009124:Muscle Proteins; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D022661:RNA, Untranslated; D007335:Insulin-Like Growth Factor II; D003907:Dexamethasone