Abstract
The human DNA binding factor GRF-1, which associates with the promoter region of the glucocorticoid receptor gene (hGR gene), is a repressor of glucocorticoid receptor transcription. The GRF-1 cDNA was cloned using polyclonal antibodies against the purified protein. The deduced amino acid sequence from the cDNA sequences show the presence of three sequence motifs characteristic of a zinc finger and one motif suggestive of a leucine zipper in which 1 cysteine is found instead of all leucines. The GRF-1 expressed in COS-1 cells has a molecular weight of 95,000 and enhances the homologous down-regulation of wild-type hGR gene expression. Biochemical analysis suggests that GRF-1 interaction is sequence specific and that transcriptional efficacy of GRF-1 is regulated through its interaction with specific sequence motif, namely 5'-GAAGGAGGTAGCGAGAAAAGAAACTG-GAGAAACTCGGT.GG-3'. The GRF-1 mRNA is 6.5 kilobases long in rat liver and human MCF-7 cells, and its level is regulated by glucocorticoids.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Amino Acid Sequence
-
Base Sequence
-
Cell Line
-
Cloning, Molecular
-
DNA / metabolism
-
DNA-Binding Proteins / genetics*
-
DNA-Binding Proteins / metabolism
-
Deoxyribonuclease I
-
GTP-Binding Proteins*
-
Gene Expression Regulation*
-
Guanine Nucleotide Exchange Factors
-
Humans
-
Molecular Sequence Data
-
Nucleic Acid Hybridization
-
Promoter Regions, Genetic
-
Receptors, Glucocorticoid / genetics*
-
Repressor Proteins / genetics*
-
Restriction Mapping
-
Transcription, Genetic
-
Tumor Suppressor Proteins*
-
ras GTPase-Activating Proteins*
-
ras-GRF1
Substances
-
ARHGAP35 protein, human
-
Arhgap35 protein, rat
-
DNA-Binding Proteins
-
Guanine Nucleotide Exchange Factors
-
RASGRF1 protein, human
-
Receptors, Glucocorticoid
-
Repressor Proteins
-
Tumor Suppressor Proteins
-
ras GTPase-Activating Proteins
-
ras-GRF1
-
DNA
-
Deoxyribonuclease I
-
GTP-Binding Proteins
Associated data
-
GENBANK/M64109
-
GENBANK/M73077
-
GENBANK/S53397
-
GENBANK/S53399
-
GENBANK/S53401
-
GENBANK/S53403
-
GENBANK/S54662
-
GENBANK/S54667
-
GENBANK/S56522
-
GENBANK/S56524