Manipulating Cell Size in Plants.

By revving up a key gene in plants--making it produce more protein than it would naturally--University of North Carolina at Chapel Hill scientists and colleagues have discovered that they are able to manipulate the size of plant cells without changing the overall size of the plant itself. The discovery is a scientific breakthrough, the researchers say, because one day it could lead to food crops more resistant to overly dry or wet conditions and enable horticulturists to manipulate plants in other useful ways.

"Before long, we should be able to control the size of wood cells in trees," says Alan M. Jones, associate professor of biology. "Since soft wood is better for making paper, for example, we could grow softer woods by increasing the size of cells in a tree trunk, or we could produce harder woods for furniture by making their cells smaller."

In research completed in 1989, Jones identified a protein he believed to be the receptor to auxin, a major plant hormone that causes cells to grow, expand, and change form. At the time, he could not link the protein to the hormone by genetic methods to prove that it was a genuine auxin receptor. Now, using what is called a reverse genetic approach, he and his...