Mapping and characterization of a retinoic acid-responsive enhancer of midkine, a novel heparin-binding growth/differentiation factor with neurotrophic activity.
MK is a gene that is activated by retinoic acid in embryonal carcinoma (EC) cells and is expressed temporarily during the mid-gestation period of mouse embryogenesis. Midkine, the product of the gene is a novel heparin-binding growth/differentiation factor with neurite outgrowth and neurotrophic activities. The regulatory DNA element in the retinoic acid-induced expression of the MK gene has been investigated. The 1.9 kb 5'-flanking region of the MK gene can mediate retinoic acid-responsive gene expression in F9 and HM-1 EC cells. Analysis of this region by deletion mutagenesis in F9 EC cells shows that there is a retinoic acid-responsive enhancer (designated as REM1) around 900 bp upstream from the transcription start site. This enhancer is composed of two sequence elements, which are located between -1006 and -895 and between -901 and -794. The core element of the upstream region (-971 to -955), whose deletion abolished the retinoic acid responsiveness, contained a sequence highly homologous to a binding site for retinoic acid receptors. Binding of a retinoic acid receptor heterodimer to this core element was verified by gel shift assay. Thus, retinoic acid and the receptor complex can directly induce the expression of a growth/differentiation factor gene.
Matsubara
S
S
Department of Biochemistry, Faculty of Medicine, Kagoshima University.
Take
M
M
Pedraza
C
C
Muramatsu
T
T
D000818:Animals; D001483:Base Sequence; D018236:Carcinoma, Embryonal / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D002454:Cell Differentiation / Q000187:drug effects; D002874:Chromosome Mapping; D016207:Cytokines / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D005091:Exons; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005815:Genetic Code; D051379:Mice; D000078792:Midkine; D008969:Molecular Sequence Data; D009414:Nerve Growth Factors / Q000235:genetics*; D014176:Protein Biosynthesis; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D016207:Cytokines; D009414:Nerve Growth Factors; D000078792:Midkine; D014212:Tretinoin