The lipoxygenase pathway in zebrafish. Expression and characterization of zebrafish ALOX5 and comparison with its human ortholog
Autor: | Dagmar Heydeck, Susan Adel, Hartmut Kühn, Christoph Ufer |
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Rok vydání: | 2015 |
Předmět: |
0301 basic medicine
animal structures ved/biology.organism_classification_rank.species Molecular Sequence Data Danio Mutagenesis (molecular biology technique) Sequence alignment Isozyme 03 medical and health sciences Mice Animals Humans Amino Acid Sequence Model organism Molecular Biology Zebrafish Peptide sequence Gene Phylogeny Genetics Arachidonate 5-Lipoxygenase biology ved/biology fungi Cell Biology Zebrafish Proteins biology.organism_classification Isoenzymes 030104 developmental biology Mutagenesis Site-Directed Sequence Alignment |
Zdroj: | Biochimica et biophysica acta. 1861(1) |
ISSN: | 0006-3002 |
Popis: | The zebrafish (Danio rerio) is frequently employed as model organism to explore vertebrate embryogenesis but little is known about the lipoxygenase pathway in this lower vertebrate. When we searched the zebrafish genome for lipoxygenase genes we detected seven different genes localized on four different chromosomes. Four of these genes (ALOX2, ALOX3a, ALOX3b, ALOX3c) share a high degree of sequence conservation with the human ALOX5 gene, which encodes for the key enzyme of mammalian leukotriene biosynthesis. Expression profiles of the corresponding transcripts indicated that the ALOX2 gene is high level expressed during zebrafish embryogenesis whereas transcripts originating from the other three paralog genes could not be detected. To functionally compare human ALOX5 with the putative zebrafish ortholog (zebrafish ALOX2) we cloned and expressed the zebrafish enzyme in pro- and eukaryotic expression systems and characterized it as arachidonic acid 5S-lipoxygenating enzyme, which also exhibits leukotriene synthase activity. Mutagenesis studies of the triad determinants (Phe359Trp, Ala424Ile, Asn425Met) altered the reaction specificity from 5S- to dominant 15S-lipoxygenation. The finding that zebrafish expresses a functional ALOX5 together with the observation that most other human leukotriene relevant genes have an ortholog in the zebrafish genome suggests the biological relevance of leukotriene signaling in lower vertebrates. |
Databáze: | OpenAIRE |
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