Scientists Find the Female Hormone Progesterone in Plant

Researchers at the University of Illinois in Chicago are reporting for the first time the discovery of the female sex hormone progesterone in a plant. Guido F. Pauli and colleagues said they have found the steroid hormone in Juglans regia (common walnut). The discovery came as a surprise since scientists thought that only animals could make progesterone. A steroid hormone, secreted by the ovaries, progesterone prepares the uterus for pregnancy and maintains pregnancy. A synthetic version, progestin, is used in birth control pills and other medications. 　

"The significance of the unequivocal identification of progesterone cannot be overstated," Pauli and colleagues wrote in the article published by the Journal of Natural Products. "While the biological role of progesterone has been extensively studied in mammals, the reason for its presence in plants is less apparent." They speculate that the hormone, like other steroid hormones, might be an ancient bioregulator that evolved billions of years ago, before the appearance of modern plants and animals. The new discovery may change scientific understanding of the evolution and function of progesterone in living things.

The original paper is available for download at http://dx.doi.org/10.1021/np9007415