HNF factors form a network to regulate liver-enriched genes in zebrafish.
Defects in some of liver-enriched genes in mammals will cause liver- and/or blood-related diseases. However, due to the fact that embryogenesis happens intrauterinally in the mammals, the function of these liver-enriched genes during liver organogenesis is poorly studied. We report here the identification of 129 genuine liver-enriched genes in adult zebrafish and show that, through in situ hybridization, 69 of these genes are also enriched in the embryonic liver. External embryogenesis coupled with the well-established morpholino-mediated gene knock-down technique in zebrafish offers us a unique opportunity to study if this group of genes plays any role during liver organogenesis in the future. As an example, preliminary study using morpholino-mediated gene knock-down method revealed that a novel liver-enriched gene leg1 is crucial for the liver expansion growth. We also report the analysis of promoter regions of 51 liver-enriched genes by searching putative binding sites for Hnf1, Hnf3, Hnf4 and Hnf6, four key transcription factors enriched in the liver. We found that promoter regions of majority of liver-enriched genes contain putative binding sites for more than one HNF factors, suggesting that most of liver-enriched genes are likely co-regulated by different combination of HNF factors. This observation supports the hypothesis that these four liver-enriched transcription factors form a network in controlling the expression of liver-specific or -enriched genes in the liver.
Cheng
Wei
W
Functional Genomics Lab, Institute of Molecular and Cell Biology, 61 Biopolis Drive, Protesos, 138673, Singapore.
Guo
Lin
L
Zhang
Zhenhai
Z
Soo
Hui Meng
HM
Wen
Chaoming
C
Wu
Wei
W
Peng
Jinrong
J
D000595:Amino Acid Sequence; D000818:Animals; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology / Q000502:physiology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D051536:Hepatocyte Nuclear Factors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D017403:In Situ Hybridization; D008099:Liver / Q000196:embryology / Q000502:physiology*; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D015027:Zebrafish / Q000033:anatomy & histology / Q000196:embryology* / Q000235:genetics* / Q000502:physiology; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
D051536:Hepatocyte Nuclear Factors; D016376:Oligonucleotides, Antisense; D029961:Zebrafish Proteins