Regulation Of Cholesterol 7-alpha-hydroxylase In The Liver - Cloning, Sequencing, And Regulation Of Cholesterol 7-alpha-hydroxylase Messenger-rna
Biochemistry & Molecular Biology
Li Y C; Wang D P; Chiang J Y L
Journal of Biological Chemistry
1990
1990-07
Journal Article or Conference Abstract Publication
n/a
Transcriptional Regulation Of The Human Cholesterol 7 Alpha-hydroxylase Gene (cyp7a) In Transiently And Stably Transfected Hepg2 Cells
Biochemistry & Molecular Biology; Cell Biology; Life Sciences & Biomedicine - Other; Topics
Marrapodi M; Wang D P; Stroup D; Chiang J Y L
Faseb Journal
1996
1996-04
Journal Article or Conference Abstract Publication
n/a
Molecular mechanism of regulation of cholesterol 7 alpha-hydroxylase gene
Chiang J Y L; Stroup D; Crestani M; Wang D P
1995
1995
Book/Monograph
n/a
THE EXPRESSION AND REGULATION OF CHOLESTEROL 7-ALPHA-HYDROXYLASE
Chiang J Y L; Karam W G; Yang T P; Wang D P
1993
1993
Book/Monograph
n/a
TRANSCRIPTIONAL REGULATION OF HUMAN CHOLESTEROL 7-ALPHA-HYDROXYLASE GENE IN HEPG2 CELLS
Biochemistry & Molecular Biology; Cell Biology; Life Sciences & Biomedicine - Other; Topics
Wang D P; Karam W G; Chiang J Y L
Faseb Journal
1994
1994-04
Journal Article
n/a
Transcriptional regulation of the human cholesterol 7 alpha-hydroxylase gene (CYP7A) in HepG2 cells.
Humans; Binding Sites; Gene Expression Regulation; Cell Line; Transfection; Base Sequence; Molecular Sequence Data; Phorbol Esters/pharmacology; DNA-Binding Proteins/genetics/metabolism; *Transcription Factors; Enzyme Repression; Cholesterol 7-alpha-Hydroxylase/biosynthesis/*genetics; Consensus Sequence; Glucocorticoids/pharmacology; Hepatocyte Nuclear Factor 3-alpha; Insulin/pharmacology; Nuclear Proteins/genetics/metabolism; Recombinant Fusion Proteins/biosynthesis; Thyroid Hormones/pharmacology; Genes; Receptors; Enzymologic/*drug effects; Genetic; *Promoter Regions; Reporter; *Transcription; Glucocorticoid/genetics/metabolism
A stable HepG2 cell line harboring a human cholesterol 7 alpha-hydroxylase (CYP7A) minigene/luciferase reporter gene construct was selected for studying transcriptional regulation of CYP7A gene promoter. Insulin and phorbol
Wang D P; Stroup D; Marrapodi M; Crestani M; Galli G; Chiang J Y
Journal of lipid research
1996
1996-09
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
Regulation of cholesterol 7 alpha-hydroxylase in the liver. Cloning, sequencing, and regulation of cholesterol 7 alpha-hydroxylase mRNA.
Female; Animals; Rats; Amino Acid Sequence; *Gene Expression Regulation; Kinetics; Base Sequence; Immunoblotting; Molecular Sequence Data; Steroid Hydroxylases/*genetics; Circadian Rhythm; DNA/genetics/isolation & purification; Restriction Mapping; Enzyme Induction; Liver/drug effects/*enzymology; Cell Fractionation; Cholesterol 7-alpha-Hydroxylase/biosynthesis/*genetics/immunology; Cholestyramine Resin/pharmacology; Cytochrome P-450 Enzyme System/genetics; Epitopes/analysis; Polyribosomes/metabolism/ultrastructure; Inbred Strains; RNA; Enzymologic; Sequence Homology; Cloning; Nucleic Acid; Messenger/*genetics; Centrifugation; Density Gradient; Molecular/methods
Monospecific antibody against purified rat liver cholesterol 7 alpha-hydroxylase cytochrome P-450 was used to screen a lambda gt11 cDNA library constructed from immuno-enriched polysomal RNA of cholestyramine-treated female rat liver. Two types of cDNA clones differing in the length of the 3'-untranslated region were identified, and DNA sequences were determined. The full length clone contains 3561 base pairs plus a long poly(A) tail. The amino acid sequence deduced from the open reading frame revealed a unique P-450 protein containing 503 amino acid residues which belonged to a new gene family designated family VII or CYP7. Southern blot hybridization experiments indicated that the minimal size of P-450 VII gene was 11 kilobase pairs (kb), and there was probably only one gene in this new family. Northern blot hybridization using specific cDNA probes revealed at least two major mRNA species of about 4.0 kb and 2.1 kb, respectively. These two mRNA species may be derived from the use of different polyadenylation signals and reverse-transcribed to two types of cDNA clones. Cholesterol 7 alpha-hydroxylase mRNAs were induced 2- to 3-fold in rat liver by cholestyramine treatment. The mRNA level was rapidly reduced upon the removal of the inducer. Similarly, cholesterol feeding induced enzyme activity, protein, and mRNA levels in the rat by 2-fold, suggesting that cholesterol is an important regulator of cholesterol 7 alpha-hydroxylase in the liver. On the other hand, dexamethasone and pregnenolone-16 alpha-carbonitrile drastically reduced the activity, protein, and mRNA levels. These experiments suggest that the induction of cholesterol 7 alpha-hydroxylase activity by cholestyramine or cholesterol and inhibition of cholesterol 7 alpha-hydroxylase activity by bile acid feedback are results of the rapid turnover of cholesterol 7 alpha-hydroxylase enzyme and mRNA levels.
Li Y C; Wang D P; Chiang J Y
The Journal of biological chemistry
1990
1990-07
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
Cloning and 5'-flanking sequence of a rat cholesterol 7 alpha-hydroxylase gene.
Animals; Rats; Amino Acid Sequence; Base Sequence; Molecular Sequence Data; Cholesterol 7-alpha-Hydroxylase/*genetics; DNA; Restriction Mapping; Genetic; Cloning; Molecular; *Promoter Regions
A cholesterol 7 alpha-hydroxylase gene containing 8 kb of the 5'-flanking region and 5 kb of the transcription region which covers exons 1 to 5 was isolated from a rat genomic library. The 2015 bp nucleotide sequence 5'-upstream from the start codon was determined. This promotor region contains many liver-enriched or -specific elements (TGT3, HNF/LF-B1), putative hormone responsive elements (TRE, GRE, RRE or RARE) and ubiquitous transcription factor binding sites (NF-1,
Chiang J Y; Yang T P; Wang D P
Biochimica et biophysica acta
1992
1992-10
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
Structure and nucleotide sequences of the human cholesterol 7 alpha-hydroxylase gene (CYP7).
Amino Acid Sequence; Base Sequence; Cholesterol 7-alpha-Hydroxylase/chemistry/*genetics; DNA; Humans; Molecular Sequence Data; Restriction Mapping
The human cholesterol 7 alpha-hydroxylase gene (CYP7) spans about 11 kb of the genome and contains six exons and five introns. Nucleotide sequences of a 5'-upstream region to exon III (5535 bp), a 5'-upstream EcoRI fragment (2575 bp), and an EcoRI fragment covering intron V to exon VI (2319 bp) have been determined. A comparison of our sequences with those reported previously unveiled numerous sequencing discrepancies that are apparently due to sequencing errors. There are only one confirmed and one possible genetic polymorphism in the promoter of this highly conserved human gene. The proximal promoter contained many consensus recognition sequences for liver-enriched transcription factors and steroid hormone receptors that may play important roles in regulation of the CYP7 gene transcription by bile acids, cholesterol, and hormones.
Wang D P; Chiang J Y
Genomics
1994
1994-03
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1006/geno.1994.1177" target="_blank" rel="noreferrer noopener">10.1006/geno.1994.1177</a>