Genomic structure of the Xenopus laevis liver transcription factor LFB1
| Autor: | Sigrid Bartkowski, Christiane Zoidl, Dirk Zapp, Gerhart U. Ryffel, Ludger Klein-Hitpass |
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| Rok vydání: | 1993 |
| Předmět: |
EMX2
Molecular Sequence Data Restriction Mapping Xenopus Homeobox A1 Biology Xenopus Proteins NKX2-3 Homeobox protein Nkx-2.5 Xenopus laevis Genetics Animals Amino Acid Sequence Hepatocyte Nuclear Factor 1-alpha CDX2 Hepatocyte Nuclear Factor 1-beta Base Sequence Sequence Homology Amino Acid Nuclear Proteins General Medicine DNA Exons HNF1B biology.organism_classification Molecular biology Introns DNA-Binding Proteins Hepatocyte Nuclear Factor 1 Homeobox Transcription Factors |
| Zdroj: | Gene. 134(2) |
| ISSN: | 0378-1119 |
| Popis: | Liver factor Bl [LFB1, also called hepatocyte nuclear factor l (HNF1)] is a tissue-specific vertebrate transcription factor that is present in the liver, intestine, stomach and kidney. The LFB1 protein contains an unusual homeobox that is characterized by an insertion of 21 amino acids (aa) not found in any other homeodomain protein. We have isolated and characterized the genomic sequences encoding the LFB1 of Xenopus laevis. By comparing the genomic sequences with the cDNA clones, we could identify nine exons. In general, the position of the introns is identical to the one previously found in the rat. However, the C-terminal activation domain of LFB1 contains, in each species, an exon that is split in two in the other species. The homeobox of the X. laevis LFB1 contains an intron at exactly the position where the 21 aa typical for LFB1 are inserted. This is in agreement with the structure found in the rat gene and supports the notion that the LFB1 homeobox evolved separately from the other genes encoding homeodomain proteins. |
| Databáze: | OpenAIRE |
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