Uncovering the Genetic Secrets of Body Size in Gobies

Scientists have long been fascinated by the diversity of body sizes in gobies, with some species reaching lengths of up to a foot and others remaining under an inch. University of Michigan postdoctoral researcher Emily Troyer led a groundbreaking study to investigate the genetic mechanisms controlling body size in these tiny fish. By examining the genetic pathways of miniature and large-bodied gobies, Troyer and her team discovered that certain genes are associated with regulating and limiting cell growth, keeping some species of goby miniaturized.

Key Takeaways:

• The study, led by University of Michigan postdoctoral researcher Emily Troyer, investigated the genetic mechanisms controlling body size in gobies, a family of over 2,000 species of fish.
• The researchers found that certain genes, CDKN1B and ING2, are associated with regulating and limiting cell growth in miniature gobies.
• By comparing the levels of gene activity between large- and small-bodied gobies, the researchers discovered that in miniature gobies, CDKN1B and ING2 are highly upregulated, while genes associated with cell multiplication and proliferation are upregulated in larger goby species.
• The study suggests that the same genetic mechanisms controlling body size are at work in both non-model species like gobies and model organisms like mice and fruit flies.
• The findings have implications for evolutionary biologists, biomedical scientists, and our understanding of the growth and development of animals.

Statistics:

• Over 2,000 species of gobies exist, ranging in size from under an inch to over a foot.
• The study examined 162 goby species and identified three groups that exhibit repeated instances of both miniaturization and large-bodied forms.
• The researchers used comparative transcriptomic techniques to examine the difference in gene expression between miniature and large-bodied gobies.
• The study found that in miniature gobies, certain genes associated with cell division and growth are highly turned on, while others are turned off.
• CDKN1B, a gene known to be an inhibitor of growth, is highly upregulated in miniature gobies and has also been found to control body size in mice.

Sources:

• University of Michigan - Ann Arbor
• Proceedings of the National Academy of Science
• Emily Troyer, University of Michigan postdoctoral researcher
• Dahiana Arcila, evolutionary biologist at the Scripps Institution of Oceanography