The Carnegie team's new research identifies a protein called GATA2 as a missing link in this communications system. This protein tells developing seedlings which type of growth to pursue.
GATA2 is part of the GATA factor class of proteins, which are found in plants, fungi and many animals. GATA factors promote the construction of a variety of new proteins, the recipes for which are encoded in DNA. It does this by switching on and off different genes. In Arabidopsis, the experimental mustard plant used in this study, there are 29 genes for different members of the GATA factor family. Some of these have been demonstrated to play a role in flower development, the metabolism of carbon and nitrogen, and the production of the green pigment chlorophyll.
Wang's team found that GATA2 switches on many genes that are turned on by light but turned off by brassinosteroid. It then showed that brassinosteroid inhibits the production of GATA2 and light stabilizes the presence of GATA2 protein in plant cells.
First, the team showed that GATA2 functions to turn on select plant growth genes in the presence of light. The scientists genetically manipulated Arabidopsis plants to cause the GATA2 protein to be overproduced. As a result, the plants started to show patterns of growing in light, even when they were in the dark. This manipulation demonstrates that GATA2 is a major promoter of light-type growth.
What's more, this is the same reaction that was produced
|Contact: Zhi-Yong Wang|