Enhancer and promoter elements directing activation and glucocorticoid repression of the. cap alpha. /sub 1/-fetoprotein gene in hepatocytes

Journal Article · Fri Apr 01 04:00:00 EST 1988 · Mol. Cell. Biol.; (United States)

DOI:https://doi.org/10.1128/MCB.8.4.1398· OSTI ID:7192090

Guertin, M; La Rue, H; Bernier, D; Wrange, O; Chevrette, M; Gingras, M C; Belanger, L

Mutations were introduced in 7 kilobases of 5'-flanking rat ..cap alpha../sub 1/-fetoprotein (AFP) genomic DNA, linked to the chloramphenicol acetyltransferase gene. AFP promoter activity and its repression by a glucocorticoid hormone were assessed by stable and transient expression assays. Stable transfection assays were more sensitive and accurate than transient expression assays in a Morris 7777 rat hepatoma recipient (Hepa7.6), selected for its strong AFP repression by dexamethasone. The segment of DNA encompassing a hepatocyte-constitutive chromatin DNase I-hypersensitive site at -3.7 kilobases and a liver developmental stage-specific site at -2.5 kilobases contains interacting enhancer elements sufficient for high AFP promoter activity in Hepa7.6 or HepG2 cells. Deletions and point mutations define an upstream promoter domain of AFP gene activation, operating with at least three distinct promoter-activating elements, PEI at -65 base pairs, PEII at -120 base pairs, and DE at -160 base pairs. PEI and PEII share homologies with albumin promoter sequences, PEII is a near-consensus nuclear factor I recognition sequence, and DE overlaps a glucocorticoid receptor recognition sequence. An element conferring glucocorticoid repression of AFP gene activity is located in the upstream AFP promoter domain. Receptor-binding assays indicate that this element is the glucocorticoid receptor recognition sequence which overlaps with promoter-activating element DE.

• Research Organization: Le Centre de Recherche en Cancerologie de l'Universite Laval, L'Hotel-Dieu de Quebec, Quebec G1R 2J6 (CA)
• OSTI ID: 7192090
• Journal Information: Mol. Cell. Biol.; (United States), Journal Name: Mol. Cell. Biol.; (United States) Vol. 8:4; ISSN MCEBD
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMAL CELLS
ANIMALS
ANTI-INFECTIVE AGENTS
ANTIBIOTICS
BIOLOGICAL FUNCTIONS
BIOLOGICAL PATHWAYS
CHLORAMPHENICOL
CHROMATIN
CORTICOSTEROIDS
DISEASES
DNA SEQUENCING
DNA-ASE
DRUGS
ENZYMES
ESTERASES
FETUSES
FUNCTIONS
GENE AMPLIFICATION
GENES
GLUCOCORTICOIDS
HEPATOMAS
HYDROLASES
HYDROXY COMPOUNDS
KETONES
LIVER CELLS
MAMMALS
MUTATIONS
NEOPLASMS
ORGANIC COMPOUNDS
PHENOTYPE
PHOSPHODIESTERASES
PREGNANES
PROTEINS
RATS
RODENTS
SOMATIC CELLS
STEROIDS
STRUCTURAL CHEMICAL ANALYSIS
TRANSFERASES
VERTEBRATES