"How Does a Single Somatic Cell Become a Whole Plant?" is one of the top 25 questions from the 125th anniversary issue of Science magazine [Science, July 1, 2005]. The complete reference is ...
Gretchen Vogel is a contributing correspondent for Science magazine. She is based in Berlin.
This question is really about developmental biology. It's closely related to the two questions that immediately precedes it in the journal: How Can a Skin Cell Become a Nerve Cell?, and What Controls Organ Regeneration?. For some reason the editors of Science seem to think that there's a fundamental difference between this question and the other two. Perhaps they think that plants control gene expression by a very different process?
The totipotency of plant cells was demonstrated half a century ago as noted in the article.
Nearly 50 years ago, scientists learned that they could coax carrot cells to undergo such embryogenesis in the lab. Since then, people have used so-called somatic embryogenesis to propagate dozens of species, including coffee, magnolias, mangos, and roses. A Canadian company has planted entire forests of fir trees that started life in tissue culture. But like researchers who clone animals (see p. 85), plant scientists understand little about what actually controls the process. The search for answers might shed light on how cells' fates become fixed during development, and how plants manage to retain such flexibility.I really don't think it's correct to say that "plant scientists understand little about what actually controls the process." Furthermore, even if there are lots of details to be worked out, I see no indication that there's some mysterious unknown process behind plant development.
This is not a fundamental question.