What Makes a Plant a Plant?


DNA sequencing has generated vast collections of genes for all types of organisms; however, determining the roles of the proteins coded within those genes is a difficult task and the functions of many of those proteins are still unknown. Researchers at the UCLA-DOE Institute for Genomics and Proteomics and at the DOE Joint Genome Institute in Walnut Creek, California, have now provided new information on the function of genes that are uniquely found in plants and green algae. Comparing the genes present in the genomes of 20 photosynthetic organisms with those of non-photosynthetic organisms, the investigators compiled GreenCut2, an inventory of nearly 600 plant-specific genes. As the function of more than half of those 600 genes is not known, this work sheds new light on genes needed for plant-specific processes, including those related to the chloroplast (the photosynthetic organelle of plant cells). Further analysis of those proteins of unknown function showed that many of them are likely involved in protein modification, gene regulation, and transport of molecules to the chloroplast. This new knowledge provides insights on plant evolution and will help researchers better understand how plants work, enabling them to harness their potential to provide alternative energy sources.


Karpowicz, S., S. E. Prochnik, A. R. Grossman, and S. S. Merchant. 2011. “The GreenCut2 Resource: A Phylogenomically-Derived Inventory of Proteins Specific to the Plant Lineage,” Journal of Biological Chemistry 286, 21427–439.