LAP, a novel member of the C/EBP gene family, encodes a liver-enriched transcriptional activator protein.
A gene, encoding a liver-enriched transcriptional activator protein (LAP) has been isolated. LAP is a 32-kD protein that stimulates the transcription of chimeric genes containing albumin D-promoter elements both in vivo and in vitro. LAP shares extensive sequence homology (71%) in its DNA-binding and leucine zipper domains with C/EBP. As a consequence, these two proteins show an indistinguishable DNA-binding specificity and readily heterodimerize. In addition, both genes, lap and cebp, are devoid of intervening sequences. Although correctly initiated transcripts from the LAP gene accumulate in the six examined tissues--liver, lung, spleen, kidney, brain, and testis--LAP protein is highly enriched in liver nuclei. Thus, the preferential accumulation of LAP protein in liver appears to be regulated post-transcriptionally.
Descombes
P
P
Department of Molecular Biology, University of Geneva, Switzerland.
Chojkier
M
M
Lichtsteiner
S
S
Falvey
E
E
Schibler
U
U
D000418:Albumins / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics*; D004742:Enhancer Elements, Genetic / Q000502:physiology; D008099:Liver / Q000378:metabolism*; D008297:Male; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009928:Organ Specificity; D011401:Promoter Regions, Genetic / Q000502:physiology; D011485:Protein Binding; D051381:Rats; D011917:Rats, Inbred Lew; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic / Q000502:physiology
D000418:Albumins; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D014157:Transcription Factors