Cardiac myoglobin deficit has evolved repeatedly in teleost fishes

Daniel J. Macqueen*, Daniel Garcia de la Serrana Castillo, Ian Alistair Johnston

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

15 Citations (Scopus)


Myoglobin (Mb) is the classic vertebrate oxygen-binding protein present in aerobic striated muscles. It functions principally in oxygen delivery and provides muscle with its characteristic red colour. Members of the Antarctic icefish family (Channichthyidae) are widely thought to be extraordinary for lacking cardiac Mb expression, a fact that has been attributed to their low metabolic rate and unusual evolutionary history. Here, we report that cardiac Mb deficit, associated with pale heart colour, has evolved repeatedly during teleost evolution. This trait affects both gill-and air-breathing species from temperate to tropical habitats across a full range of salinities. Cardiac Mb deficit results from total pseudogenization in three-spined stickleback and is associated with a massive reduction in mRNA level in two species that evidently retain functional Mb. The results suggest that near or complete absence of Mb-assisted oxygen delivery to heart muscle is a common facet of teleost biodiversity, even affecting lineages with notable oxygen demands. We suggest that Mb deficit may affect how different teleost species deal with increased tissue oxygen demands arising under climate change.

Original languageEnglish
Article number20140225
Number of pages5
JournalBiology Letters
Issue number6
Publication statusPublished - 11 Jun 2014


  • Myoglobin
  • Oxygen supply
  • Fish evolution
  • Climate change
  • Thermal tolerance
  • Limitation
  • Expression
  • Oxygen


Dive into the research topics of 'Cardiac myoglobin deficit has evolved repeatedly in teleost fishes'. Together they form a unique fingerprint.

Cite this