Insulin-like growth factor I and II gene expression in Balb/C mouse liver during postnatal development.
We studied the developmental shift from IGF-II to IGF-I mRNA synthesis in Balb/C mouse liver. IGF-I mRNA levels were low at birth, increased with age to peak at weaning, and IGF-I gene expression again increased during puberty. IGF-II expression was high during early postnatal development, but became nondetectable at weaning. Thus in early life there is a reciprocal relationship of rising IGF-I and falling IGF-II mRNA. Northern analysis revealed four IGF-I mRNA transcripts ranging from 1.1-7.0 kb, with the 1.1 kb being the most prominent. Five IGF-II transcripts ranging from 1.7-4.0 kb were found, with the 4.0 kb being the most prominent. The pattern of Serum IGF-I and IGF-II values paralleled liver IGF-I and IGF-II mRNA levels.
Singh
J S
JS
Department of Pediatrics, University of California, School of Medicine, Davis.
Rall
L B
LB
Styne
D M
DM
D000375:Aging; D000818:Animals; D015152:Blotting, Northern; D015870:Gene Expression; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis*; D007335:Insulin-Like Growth Factor II / Q000096:biosynthesis*; D008099:Liver / Q000254:growth & development / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C / Q000254:growth & development; D012333:RNA, Messenger
D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II