Sex over survival: Reproductive trait in fish impedes tissue regeneration

Oct 14, 2013
Female zebrafish regenerate their pectoral fins after amputation injury, while a high percentage of male zebrafish show defective regeneration. Credit: Developmental Cell, Kang et al.

New research on the reproductive habits of zebrafish offers an explanation as to why some animals' bodies repair tissues. The research team previously noticed that male zebrafish regenerate their pectoral fins poorly, as compared to females. Their latest findings, publishing in the October 14 issue of the Cell Press journal Developmental Cell, reveal the basis for this sex-specific regenerative deficiency: structures that are used to improve reproductive success. The scenario represents an example of the tradeoffs between reproduction and survival.

Led by first author Junsu Kang, the scientists identified anatomical structures that male fish use during mating that produce a signal that impedes regeneration of the after injury. As such, fish appear to trade an ancient ability to regenerate easily for a new-found way of enhancing . This valuable information could help scientists begin to explain why humans are less able to regenerate tissue and could also be used to improve the body's tissue regenerative capacity.

"We discovered that male have a very important set of structures on their pectoral fins that they use for breeding and that these structures secrete a potent molecular inhibitor of a key signaling pathway to aid their cycles of regular replacement," explains senior author Kenneth Poss of Duke University Medical Center.

Higher vertebrates like mammals generally have a diminished capacity for tissue regeneration compared with lower vertebrates like fish and salamanders. "The biology we describe here suggests a new paradigm for how tissue regenerative capacity may be lost during species evolution," says Poss. The researchers speculate that natural selection acting on traits like sexual features could have detrimental effects on tissue regenerative potential. For example, male zebrafish with more numerous or more effective breeding ornaments—and thus lower regenerative potential—might contribute more to the gene pool, phasing out regenerative potential over generations.

Spiked structures on male zebrafish pectoral fins are important for mating but also produce a potent signaling inhibitor. Presence of this inhibitor disrupts regeneration of fin tissue after amputation injury. Credit: Developmental Cell, Kang et al.

Poss notes that growing attention in the field of is being paid to factors that block signaling pathways. "Our results indicate that the presence or restriction of a pathway inhibitor is critical to whether regeneration occurs normally, providing new fuel for ideas of how to promote regeneration after injury in humans."

Explore further: Geneticists solve 40-year-old dilemma to explain why duplicate genes remain in the genome

More information: Developmental Cell, Kang et al.: "Local Dkk1 Crosstalk from Breeding Ornaments Impedes Regeneration of Injured Male Zebrafish Fins." dx.doi.org/10.1016/j.devcel.2013.08.015

Related Stories

Do salamanders hold the solution to regeneration?

May 20, 2013

Salamanders' immune systems are key to their remarkable ability to regrow limbs, and could also underpin their ability to regenerate spinal cords, brain tissue and even parts of their hearts, scientists have ...

Heading for regeneration

Jul 24, 2013

The rabbit can't do it, neither can a frog, but zebrafish and axolotls can and flatworms are true masters of the craft: Regeneration. Why some animals can re-grow lost body parts or organs while others cannot ...

Study identifies how zebrafish regrow their brains

Nov 09, 2012

(Medical Xpress)—An international team of scientists has discovered the mechanism by which zebrafish can re-grow brain neurons after they have suffered traumatic brain injury, and that this mechanism is ...

Fingernails reveal clues to limb regeneration

Jun 12, 2013

Mammals possess the remarkable ability to regenerate a lost fingertip, including the nail, nerves and even bone. In humans, an amputated fingertip can sprout back in as little as two months, a phenomenon ...

Scientists identify mammal model of bladder regeneration

Oct 12, 2012

While it is well known that starfish, zebrafish and salamanders can re-grow damaged limbs, scientists understand very little about the regenerative capabilities of mammals. Now, researchers at Wake Forest Baptist Medical ...

Recommended for you

MaxBin: Automated sorting through metagenomes

Sep 29, 2014

Microbes – the single-celled organisms that dominate every ecosystem on Earth - have an amazing ability to feed on plant biomass and convert it into other chemical products. Tapping into this talent has ...

User comments : 0