Illinois animal biology professor Christina Cheng led a study that traced the evolution of a gene for an antifreeze protein in an Antarctic fish from the gene for a protein with an entirely different function.
CHAMPAIGN, Ill. Researchers report that they are the first to show in molecular detail how one gene evolved two competing functions that eventually split up - via gene duplication - to pursue their separate destinies. The study, in the Proceedings of the National Academy of Sciences, validates a decades-old hypothesis about a key mechanism of evolution. The study also confirms the ancestry of a family of "antifreeze proteins" that helps the Antarctic eelpout survive in the frigid waters of the Southern Ocean. "I'm always asking the question of where these antifreeze proteins come from," said University of Illinois animal biology professor Christina Cheng , who has spent three decades studying the genetic adaptations that enable Antarctic fish to survive in one of the coldest zones on the planet. "The cell usually does not create new proteins from scratch." Scientists have known since 2001 that the sequence of genes coding for a family of antifreeze proteins (known as AFP III) was very similar to part of a sequence of a gene that codes for a cellular enzyme in humans. Since Antarctic fish also produce this enzyme, sialic acid synthase (SAS), it was thought that the genes for these antifreeze proteins had somehow evolved from a duplicate copy of the SAS gene.
TO READ THIS ARTICLE, CREATE YOUR ACCOUNT
And extend your reading, free of charge and with no commitment.
