BLOOMINGTON, Ind. -- New information about early Native Americans' horticultural practices comes not from hieroglyphs or other artifacts, but from a suite of four gene duplicates found in wild and domesticated sunflowers.
In an upcoming issue of Current Biology, Indiana University Bloomington biologists present the first concrete evidence for how gene duplications can lead to functional diversity in organisms. In this case, the scientists learned how duplications of a gene called FLOWERING LOCUS T, or FT, could have evolved and interacted to prolong a flower's time to grow. A longer flower growth period means a bigger sunflower -- presumably an attribute of great value to the plant's first breeders.
"Our paper shows how gene duplication creates potential for evolutionary innovation not just through creating new gene content but also through new interactions among duplicates," said Ben Blackman, the report's lead author.
Blackman conducted the research as an IU Bloomington Ph.D. student. He is now a postdoctoral fellow at Duke University.
Biologists have long thought the accidental duplication of genetic material provides important fodder for evolution. Less risky than modifying an existing, possibly important gene, duplicates offer an out -- one copy can continue its normal activities while the other copy acquires new functions. That's a hypothesis, anyway. The Current Biology paper suggests reality may be a little more complex.
FT genes play a role in sensitizing flowering plants to seasons, and their expression is usually triggered by changes in day length. Some flowering plants express FT genes early in the growing season as days get longer. Sunflower FT genes are expressed toward the end of the growing season when days are getting shorter. As far as biologists know, all flowering plants have at least one FT gene.
Blackman and his colleagues identified four FT genes in sunflower, Helian
|Contact: David Bricker|