435-bp liver regulatory sequence in the liver fatty acid binding protein (L-FABP) gene is sufficient to modulate liver regional expression in transgenic zebrafish.
Liver fatty acid binding protein (L-FABP) is a small protein that is thought to play an important role in the intracellular binding and trafficking of long chain fatty acids in the liver. Expression of the gene encoding the zebrafish liver fatty acid binding protein is regulated by a 435-bp distal region (-1944 to -1510) of the L-FABP promoter. The 435-bp sequence is sufficient for gene activation in the liver primordia (or bud) and continues to be active in the adult liver when positioned adjacent to the SV40 basal promoter and linked directly to green fluorescent protein. The 435-bp sequence region has two distinct liver regulatory elements, A (-1944 to -1623) and B (-1622 to -1510), and contains multiple putative consensus binding sites. The element A sequence includes two consensus HFH and one HNF-1alpha site and the element B sequence includes one consensus HNF-3beta site. Deletion of an internal 435-bp fragment (-1944 to -1510) including the A and B elements totally ablated the liver-specific activity of the zebrafish L-FABP gene promoter. Deletion of either of the two elements reduces the liver activity. Mutation of the HNF-1alpha site or either of the two HFH sites in the A element or the HNF-3beta site in the B element significantly altered specificity in the liver primordia of transient expression embryos. The importance of the HNF-1alpha consensus binding site in the A element and the HNF-3beta consensus binding site in the B element within the 435-bp distal region of the L-FABP promoter region suggests that combinatorial interactions between multiple regulatory factors are responsible for the gene expression of L-FABP in the liver.
Her
Guor Mour
GM
Laboratory of Marine Molecular Biology and Biotechnology, Institute of Zoology, Academia Sinica, Taipei, Taiwan, Republic of China.
Yeh
Yang-Hui
YH
Wu
Jen-Leih
JL
D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000235:genetics* / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000378:metabolism; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D017353:Gene Deletion; D005786:Gene Expression Regulation; D049452:Green Fluorescent Proteins; D051537:Hepatocyte Nuclear Factor 1; D051538:Hepatocyte Nuclear Factor 1-alpha; D051539:Hepatocyte Nuclear Factor 1-beta; D051542:Hepatocyte Nuclear Factor 3-beta; D022781:Hepatocytes / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008164:Luminescent Proteins / Q000378:metabolism; D051379:Mice; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D019076:Transgenes; D015027:Zebrafish; D029961:Zebrafish Proteins
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C493320:Fabp1 protein, mouse; C493321:Fabp1 protein, rat; C082667:Fabp5 protein, mouse; C086936:Fabp7 protein, mouse; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; C496503:Foxa2 protein, mouse; C496504:Foxa2 protein, rat; D051538:Hepatocyte Nuclear Factor 1-alpha; C496488:Hnf1a protein, mouse; C496489:Hnf1a protein, rat; C496496:Hnf1b protein, mouse; D008164:Luminescent Proteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D029961:Zebrafish Proteins; C490175:fabp7a protein, zebrafish; C496498:hnf1ba protein, zebrafish; D051537:Hepatocyte Nuclear Factor 1; D051542:Hepatocyte Nuclear Factor 3-beta; D051539:Hepatocyte Nuclear Factor 1-beta; D049452:Green Fluorescent Proteins