Identification of a lipopolysaccharide inducible transcription factor in murine macrophages.
To study macrophage genes activated by lipopolysaccharide (LPS) we have constructed a cDNA library using the mouse macrophage cell line, RAW 264.7. By differential screening, a gene, designated LRG-21, was identified that showed nucleic acid sequence homology to rat liver regenerating factor-1 (LRF-1) and human activating transcription factor-3 (ATF3). Both LRG-21 and LRF-1 are transcribed within an hour following stimulation and in the absence of protein synthesis. The predicted protein sequence of LRG-21 consists of 181 amino acids with a molecular weight of 20.7 kDa. All three sequences contain basic and leucine zipper regions characteristic of the c-Fos and c-Jun family of transcription factors, but the remainder of the sequences are unrelated to this family. Recombinant LRG-21 has been shown to bind to a phorbol ester promoter element. Additional experiments have shown that LRG-21 is also induced by interferon-gamma (IFN-gamma) and by interleukin-4 (IL-4) in both RAW264.7 cells and murine peritoneal macrophages. Based on these observations, it is likely that LRG-21 plays an important role in macrophage activation.
Drysdale
B E
BE
Department of Research Service, Baltimore VA Medical Center, MD 21201, USA.
Howard
D L
DL
Johnson
R J
RJ
D051700:Activating Transcription Factor 3; D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects; D001483:Base Sequence; D002460:Cell Line; D015448:Leukemia, B-Cell; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008262:Macrophage Activation / Q000235:genetics*; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics* / Q000302:isolation & purification; D014407:Tumor Cells, Cultured
D051700:Activating Transcription Factor 3; C103002:Atf3 protein, mouse; D008070:Lipopolysaccharides; D014157:Transcription Factors