PUBLICATION
A Globin Gene of Ancient Evolutionary Origin in Lower Vertebrates: Evidence for Two Distinct Globin Families in Animals
- Authors
- Roesner, A., Fuchs, C., Hankeln, T., and Burmester, T.
- ID
- ZDB-PUB-040914-1
- Date
- 2005
- Source
- Mol. Biol. Evol. 22(1): 12-20 (Journal)
- Registered Authors
- Keywords
- globin, hemoglobin, neuroglobin, gene duplication, intron sliding
- MeSH Terms
-
- Amino Acid Sequence
- Animals
- Anura/genetics*
- Conserved Sequence
- Evolution, Molecular*
- Fishes/genetics*
- Globins/genetics*
- Globins/metabolism
- Molecular Sequence Data
- Phylogeny
- Protein Binding
- RNA, Messenger/metabolism
- Sequence Homology, Amino Acid
- PubMed
- 15356282 Full text @ Mol. Biol. Evol.
Citation
Roesner, A., Fuchs, C., Hankeln, T., and Burmester, T. (2005) A Globin Gene of Ancient Evolutionary Origin in Lower Vertebrates: Evidence for Two Distinct Globin Families in Animals. Mol. Biol. Evol.. 22(1):12-20.
Abstract
Hemoglobin, myoglobin, neuroglobin and cytoglobin are four types of vertebrate globins with distinct tissue-distributions and functions. Here we report the identification of a fifth and novel globin gene from fish and amphibians, which has apparently been lost in the evolution of higher vertebrates (Amniota). Because its function is presently unknown, we tentatively call it globin X (GbX). Globin X sequences were obtained from three fish species, the zebrafish Danio rerio, the goldfish Carassius auratus and the pufferfish Tetraodon nigroviridis, and the clawed frog Silurana tropicalis. Globin X sequences are distinct from vertebrate hemoglobins, myoglobins, neuroglobins and cytoglobins. Globin X displays the highest identity scores with neuroglobin ( approximately 26 to 35%), although it is not a neuronal protein, as revealed by RT-PCR experiments on goldfish RNA from various tissues. The distal ligand-binding and the proximal heme-binding histidines (E7 and F8), as well as the conserved phenylalanine CD1 are present in the globin X sequences, but due to extensions at the N- and C-termini the globin X proteins are longer than the typical 8-alpha helical globins and comprise about 200 amino acids. In addition to the conserved globin-introns at helix positions B12.2 and G7.0, the globin X genes contain two introns in E10.2 and H10.0. The intron in E10.2 is shifted by one bp in respect to the vertebrate neuroglobin gene (E11.0), providing possible evidence for an intron sliding event. Phylogenetic analyses confirm an ancient evolutionary relationship of globin X with neuroglobin and suggest the existence of two distinct globin types in the last common ancestor of Protostomia and Deuterostomia.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping