Cloning and biological analysis of the zebrafish (Danio rerio) insulin-like growth factor binding protein-2 proximal promoter region.
Insulin-like growth factor binding protein 2 (IGFBP-2) plays an important role in the regulation of IGF's action and endocrinology in fish. To understand the molecular mechanism which controls transcription of the IGFBP-2 gene, we cloned and sequenced the IGFBP-2 proximal promoter region of the zebrafish IGFBP-2 gene and characterized its activity by firefly luciferase transient transfection expression assays. Different fragments of the zebrafish IGFBP-2 5'-flanking region were transfected into Hela and ZFL cells. In these cell lines, maximum promoter activity was located in the 900 base pairs (bp) of the zebrafish IGFBP-2 5' flanking region in the ZFL cell line and 318 bp of the zebrafish IGFBP-2 5' flanking region in the Hela cell line. The in vivo actions of the IGFBP-2 promoter on developmental stage expression were further investigated in transgenic zebrafish in which an IGFBP-2 (900-bp) promoter-driven green fluorescent protein encoding the GFP cDNA transgene was microinjected into zebrafish embryos. Morphological and RT-PCR studies of transgenic zebrafish indicated that the IGFBP-2 promoter-driven GFP transcripts appeared for the first time in the 32-cell stage. These results indicate that the IGFBP-2 promoter is active in a development-specific manner. These results suggest that the IGFBP-2 promoter plays an important role in teleost embryo growth.
Chen
Jyh-Yih
JY
Marine Research Station, Institute of Zoology, Academia Sinica, Ilan, Taiwan, Republic of China.
Chou
Ming-Jun
MJ
Gong
Hong-Yi
HY
Huang
Tzou-Chi
TC
Wu
Jen-Leih
JL
Kuo
Ching-Ming
CM
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D048888:Fireflies / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D014162:Transfection; D015027:Zebrafish / Q000235:genetics*
D018971:Insulin-Like Growth Factor Binding Protein 2