Advancing Cell Biology and Functional Genomics in Maize Using Fluorescent Protein-Tagged Lines

Genomic resources have significantly impacted plant biology research in recent years. Cell biology has been further enabled by an ongoing revolution in visualization technologies. Using fluorescent proteins (FPs), we now have unprecedented views of cellular architecture, and we can study real-time dynamics of cell structure, function, and protein localization. To date, these technologies have been most widely used in Arabidopsis (Arabidopsis thaliana); however, the grasses provide a unique opportunity to study the underlying mechanisms and inter-related controls of cell growth, morphogenesis, and physiology in lead- ing crop models. Here, we present a resource that leverages the emerging maize (Zea mays) genome sequence to de- velop tools to study protein structure and function in a cellular context. Traditionally, such studies relied on fixed tissue or FP fusions driven by constitutive pro- moters, which can lead to significant artifacts. The maize genome sequence now provides access to reg- ulatory regions that can be used to drive native ex- pression. We have developed streamlined methods to generate maize FP-tagged lines using these regulatory elements, allowing analysis of tissue-specific expres- sion and localized function. Identification of diverse proteins that function in specific subcellular compart- ments will provide the tools for understanding basic developmental, biochemical, and physiological pro- cesses in maize, with direct application potential for crop improvement.