6533b81ffe1ef96bd127731c
RESEARCH PRODUCT
Evolution of tissue-specific keratins as deduced from novel cDNA sequences of the lungfish Protopterus aethiopicus.
Jürgen MarklChristian HunzingerMiriam BremerMichael Schaffeldsubject
HistologyDNA ComplementaryMolecular Sequence DataFluorescent Antibody Techniquemacromolecular substancesPeptide MappingPathology and Forensic MedicineEvolution MolecularPeptide mass fingerprintingComplementary DNAKeratinAnimalsElectrophoresis Gel Two-DimensionalAmino Acid SequencePolyacrylamide gel electrophoresisLungfishchemistry.chemical_classificationProtopterusintegumentary systembiologyPhylogenetic treeLampreyFishesCell BiologyGeneral MedicineAnatomybiology.organism_classificationchemistryEvolutionary biologySpectrometry Mass Matrix-Assisted Laser Desorption-IonizationKeratinsdescription
Lungfishes are possibly the closest extant relatives of the land vertebrates (tetrapods). We report here the cDNA and predicted amino acid sequences of 13 different keratins (ten type I and three type II) of the lungfish Protopterus aethiopicus. These keratins include the orthologs of human K8 and K18. The lungfish keratins were also identified in tissue extracts using two-dimensional polyacrylamide gel electrophoresis, keratin blot binding assays and immunoblotting. The identified keratin spots were analyzed by peptide mass fingerprinting which assigned seven sequences (inclusively Protopterus K8 and K18) to their respective protein spot. The peptide mass fingerprints also revealed the fact that the major epidermal type I and type II keratins of this lungfish have not yet been sequenced. Nevertheless, phylogenetic trees constructed from multiple sequence alignments of keratins from lungfish and distantly related vertebrates such as lamprey, shark, trout, frog, and human reveal new insights into the evolution of K8 and K18, and unravel a variety of independent keratin radiation events.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-03-01 | European journal of cell biology |