Differential regulation of IGFBP-2 and IGFBP-5 gene expression by vitamin A status in Japanese quail.
To investigate the involvement of the insulin-like growth factor (IGF) system in vitamin A (VA)-supported growth, we examined the effects of VA status on IGF binding protein (IGFBP)-2 and -5 gene expression in Japanese quail. VA deficiency caused a reduction in IGFBP-2 mRNA only in lung, without effect in other tissues. However, the expression of IGFBP-5 mRNA was more sensitive to the change of VA status. IGFBP-5 mRNA levels were significantly reduced by VA depletion in a tissue-specific manner, which preceded the decrease in body weight. A single injection of retinoic acid or retinol to VA-deficient quail did not affect the levels of IGFBP-2 mRNA, but it rapidly induced the expression of IGFBP-5 mRNAs in some tissues. These results are the first to show that gene expression of some IGFBPs in vivo are under the control of VA status and suggest a possible involvement of the IGF system in mediating the physiological actions of VA in the growth of Japanese quail.
Fu
Z
Z
Laboratory of Nutritional Biochemistry, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113 - 8657, Japan.
Noguchi
T
T
Kato
H
H
D000375:Aging / Q000378:metabolism; D000818:Animals; D003370:Coturnix / Q000502:physiology*; D004032:Diet; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics / Q000502:physiology*; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000096:biosynthesis* / Q000235:genetics; D018975:Insulin-Like Growth Factor Binding Protein 5 / Q000096:biosynthesis* / Q000235:genetics; D023282:Nuclease Protection Assays; D009752:Nutritional Status / Q000502:physiology*; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D014018:Tissue Distribution; D014801:Vitamin A / Q000502:physiology*
D018971:Insulin-Like Growth Factor Binding Protein 2; D018975:Insulin-Like Growth Factor Binding Protein 5; D012333:RNA, Messenger; D014801:Vitamin A