Related Experiment Video
Updated: Aug 18, 2026

Immunostaining Phospho-epitopes in Ciliated Organs of Whole Mount Zebrafish Embryos
Published on: February 19, 2016
Evolution of tissue-specific keratins as deduced from novel cDNA sequences of the lungfish Protopterus aethiopicus
Michael Schaffeld1, Miriam Bremer, Christian Hunzinger
1Institut für Zoologie, Johannes Gutenberg-Universität, Mallerweg 6, D-55099 Mainz, Germany.
Abstract:
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.
Related Concept Videos
Multi-species Conserved Sequences
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Evolutionary Relationships through Genome Comparisons
Gene Evolution - Fast or Slow?
In contrast, regions which code...
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Convergent Evolution
Synteny and Evolution
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...

