Glucocorticoid coordinate regulation of type I procollagen gene expression and procollagen DNA-binding proteins in chick skin fibroblasts

Journal Article · Tue Apr 19 04:00:00 EDT 1988 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00408a013· OSTI ID:7253561

Cockayne, D; Cutroneo, K R

Nuclei were isolated from control and dexamethasone-treated (2 h) embryonic chick skin fibroblasts and transcribed in vitro. Nuclei isolated from dexamethasone-treated fibroblasts transcribed less pro..cap alpha..1(I) and pro..cap alpha..2(I) mRNAs but not ..beta..-actin mRNA. Fibroblasts receiving dexamethasone and (5,6-/sup 3/H)uridine also demonstrated decreased synthesis of nuclear type I procollagen mRNAs but not ..beta..-actin mRNA. In fibroblasts treated with cycloheximide the newly synthesized nuclear type I procollagen mRNA species were markedly decreased. An enhanced inhibitory effect was observed when fibroblasts were treated with cycloheximide plus dexamethasone. Since the studies above demonstrate that active protein synthesis is required to maintain the constitutive expression of the type I procollagen genes, the authors determined if glucocorticoids regulate DNA-binding proteins with sequence specificity for the ..cap alpha..2(I) procollagen gene. Nuclear protein blots were probed with the /sup 32/P-end-labeled pBR322 vector DNA and /sup 32/P-end-labeled ..cap alpha..2(I) procollagen promoter containing DNA. Nonhistone proteins remained bound to labeled DNA at stringency washes of 0.05 and 0.1 M NaCl. As the ionic strength was increased to 0.2 and 0.3 M NaCl, the nonhistone-protein DNA binding was preferentially lost. Only the low molecular weight proteins remained bound to labeled DNA at the highest ionic strength, indicating nonspecific binding of these nuclear proteins. Dexamethasone treatment resulted in an increase of binding of nonhistone proteins to vector- and promoter-labeled DNAs over that observed in control fibroblasts at stringency washes of 0.05 and 0.1 M NaCl and to a lesser extent at 0.2 M NaCl. The binding specificities of nonhistone proteins for the ..cap alpha..2(I) procollagen promoter containing DNA were calculated.

• Research Organization: Univ. of Vermont, Burlington (USA)
• OSTI ID: 7253561
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 27:8; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMAL CELLS
ANIMALS
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIRDS
BODY
CELL CONSTITUENTS
CELL NUCLEI
CHICKENS
COLLAGEN
CONNECTIVE TISSUE CELLS
CORTICOSTEROIDS
DAYS LIVING RADIOISOTOPES
DEXAMETHASONE
DNA
FIBROBLASTS
FOWL
GENE REGULATION
GLUCOCORTICOIDS
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
IN VITRO
ISOTOPES
KETONES
LABELLED COMPOUNDS
LIGHT NUCLEI
MOLECULAR WEIGHT
NUCLEI
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PREGNANES
PROTEINS
PYRIMIDINES
RADIOISOTOPES
RIBOSIDES
SCLEROPROTEINS
SKIN
SOMATIC CELLS
STEROIDS
TRANSCRIPTION
TRITIUM COMPOUNDS
URACILS
URIDINE
VERTEBRATES