BIOMAT Database Logo BIOMAT Database Logo

Cloning of the functional promoter for human insulin-like growth factor binding protein-4 gene: endogenous regulation. 1997

B Dai, and S G Widen, and R Mifflin, and P Singh
Department of Anatomy and Neurosciences, University of Texas Medical Branch, Galveston 77555-1043, USA.

The majority of the colon cancers analyzed to-date express insulin-like growth factor binding protein (IGFBP)-4, and antisense inhibition of IGFBP-4 messenger RNA (mRNA) confers a growth advantage to the cells in response to endogenous and exogenous IGFs. We recently reported a significant up-regulation of IGFBP-4 expression in a human colon cancer cell line (CaCo2) on spontaneous differentiation of the cells in culture. This suggests that the expression of IGFBP-4 may be related to growth and differentiation of colon cancer cells. To study the endogenous factors involved in the transcriptional regulation of IGFBP-4, we have isolated and sequenced the human (h) IGFBP-4 promoter. The approximately 1.3 kilobase pair (kb) 5' flanking region of the IGFBP-4 gene is GC rich and possesses several potential regulatory elements. These elements include a typical TATA box with sequence TATAA, located -299 nt from the initiation ATG codon. The cap site is located 14 nt downstream of the TATA box as determined by primer extension analysis. A 1.4-kb DNA fragment including the 1.254 kb 5' flanking region of the hIGFBP-4 gene was subcloned into a luciferase reporter vector (pGL-2 basic) either in the sense (BP-4-S-pGL) (S) or antisense (BP-4-AS-pGL) (AS) (negative control) orientation, relative to the luciferase coding sequence in the vector. CaCo2 cells were transfected with either the S or the AS vectors on days 2-10 of culture; cotransfection with the SV40-beta-Galactidose (Gal) vector was used to correct for transfection efficiency. The ratio of luciferase/beta-Gal expression by CaCo2 cells transfected with the S vectors increased significantly from days 3 and 4 to days 5 and 6 of culture, followed by a sharp decline on days 7-9, resembling the pattern of endogenous expression of IGFBP-4 by the cells; the expression of luciferase by the AS vectors remained low and insignificant. These results thus suggest that the approximately 1.4 kb 5' flanking region of the IGFBP-4 gene contains the cis elements required for regulation of the IGFBP-4 gene. Cloning and sequencing of the functional hIGFBP-4 promoter will enable us, for the first time, to study the endogenous factors/mechanisms responsible for the growth/differentiation (cell density) associated regulation of IGFBP-4 expression in colonic epithelial cells.

UI MeSH Term Description Entries
D008969 Molecular Sequence Data Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories. Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D011401 Promoter Regions, Genetic DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes. rRNA Promoter,Early Promoters, Genetic,Late Promoters, Genetic,Middle Promoters, Genetic,Promoter Regions,Promoter, Genetic,Promotor Regions,Promotor, Genetic,Pseudopromoter, Genetic,Early Promoter, Genetic,Genetic Late Promoter,Genetic Middle Promoters,Genetic Promoter,Genetic Promoter Region,Genetic Promoter Regions,Genetic Promoters,Genetic Promotor,Genetic Promotors,Genetic Pseudopromoter,Genetic Pseudopromoters,Late Promoter, Genetic,Middle Promoter, Genetic,Promoter Region,Promoter Region, Genetic,Promoter, Genetic Early,Promoter, rRNA,Promoters, Genetic,Promoters, Genetic Middle,Promoters, rRNA,Promotor Region,Promotors, Genetic,Pseudopromoters, Genetic,Region, Genetic Promoter,Region, Promoter,Region, Promotor,Regions, Genetic Promoter,Regions, Promoter,Regions, Promotor,rRNA Promoters
D003001 Cloning, Molecular The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells. Molecular Cloning
D005786 Gene Expression Regulation Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation. Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001483 Base Sequence The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence. DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D014158 Transcription, Genetic The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION. Genetic Transcription
D018938 Caco-2 Cells Human colonic ADENOCARCINOMA cells that are able to express differentiation features characteristic of mature intestinal cells, such as ENTEROCYTES. These cells are valuable in vitro tools for studies related to intestinal cell function and differentiation. Caco 2 Cells,Caco-2 Cell,Cell, Caco-2,Cells, Caco-2
D018974 Insulin-Like Growth Factor Binding Protein 4 One of the six homologous soluble proteins that bind insulin-like growth factors (SOMATOMEDINS) and modulate their mitogenic and metabolic actions at the cellular level. IGF-Binding Protein 4,IGFBP-4,IGF Binding Protein 4,Insulin Like Growth Factor Binding Protein 4

Related Publications

B Dai, and S G Widen, and R Mifflin, and P Singh
Cloning and characterization of the promoter for the rat insulin-like growth factor-binding protein-3 gene.
February 1995, Endocrinology,
B Dai, and S G Widen, and R Mifflin, and P Singh
Structure and transcription regulation of the human insulin-like growth factor binding protein 4 gene (IGFBP4).
May 1998, Genomics,
B Dai, and S G Widen, and R Mifflin, and P Singh
Characterization of the chromosomal gene and promoter for human insulin-like growth factor binding protein-5.
April 1994, The Journal of biological chemistry,
B Dai, and S G Widen, and R Mifflin, and P Singh
Regulation of insulin-like growth factor (IGF)-binding protein-4 availability in normal human osteoblast-like cells: role of endogenous IGFs.
January 1995, The Journal of clinical endocrinology and metabolism,
B Dai, and S G Widen, and R Mifflin, and P Singh
Cloning of the rat insulin-like growth factor-binding protein-2 gene and identification of a functional promoter lacking a TATA box.
December 1990, Molecular endocrinology (Baltimore, Md.),
B Dai, and S G Widen, and R Mifflin, and P Singh
Aberrant promoter methylation of insulin-like growth factor binding protein-3 gene in human cancers.
February 2007, International journal of cancer,
B Dai, and S G Widen, and R Mifflin, and P Singh
Structure of the rat insulin-like growth factor binding protein-4 gene.
February 1993, Biochemical and biophysical research communications,
B Dai, and S G Widen, and R Mifflin, and P Singh
Insulin-like growth factor-binding protein-3 in porcine ovarian granulosa cells: gene cloning, promoter mapping, and follicle-stimulating hormone regulation.
April 2004, Endocrinology,
B Dai, and S G Widen, and R Mifflin, and P Singh
Molecular cloning of a new human insulin-like growth factor binding protein.
April 1991, Biochemical and biophysical research communications,
B Dai, and S G Widen, and R Mifflin, and P Singh
Cloning and expression of human insulin-like growth factor binding protein 3.
January 1990, Growth factors (Chur, Switzerland),
Copied contents to your clipboard!