Identification and characterisation of the egr-1 gene product as an inducible, short-lived, nuclear phosphoprotein.
The egr-1 gene (also termed NGFI-A, zif/268 and Krox24) is predicted to encode a protein with three 'zinc finger' domains. Analogous DNA-binding motifs are present in several putative transcriptional regulatory proteins. The mRNA of egr-1 is rapidly and transiently induced by a variety of growth factors in diverse cell types. We have used a synthetic peptide corresponding to the C-terminus of the predicted egr-1 protein to generate mouse and rabbit polyclonal antibodies. These antibodies have been used to identify the egr-1 protein, designated p75egr-1, by immunoprecipitation, immunoblotting and immunocytochemical analyses. p75egr-1 is induced within 1-2 h of mitogenic stimulation and has a half-life of under 2 h. The protein is phosphorylated and has been localised to the nucleus by both immunocytochemical analysis and biochemical fractionation. The egr-1 protein is released from nuclei under isotonic or hypertonic salt conditions or by treatment with DNAase and binds double-stranded DNA in vitro. Consistent with the distribution described for the mRNA the egr-1 protein is abundantly expressed in normal rat brain.
Imperial Cancer Research Fund Laboratories, London, UK.
C M
CM
Waters
D C
DC
Hancock
G I
GI
Evan
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D001921:Brain / Q000166:cytology / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D051766:Early Growth Response Protein 1; D005455:Fluorescent Antibody Technique; D017874:Immediate-Early Proteins; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D011233:Precipitin Tests; D051381:Rats; D014157:Transcription Factors / Q000235:genetics* / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D004268:DNA-Binding Proteins; D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse; C486110:Egr1 protein, rat; D017874:Immediate-Early Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D014157:Transcription Factors; D004247:DNA