An Investigation to Identify Transcription Factors That Regulate the Radial Root Growth in Arabidopsis and Radish

Background: Very little is known about the yield control of root crops that serve as valuable sources for food and energy. Therefore, it is in our interest to identify genetic factors that are controlling their radial growth. Radish would be an ideal model plant for understanding root growth in other root crops, because it has a short life span and moderate genome size and it can easily employ the tools developed with Arabidopsis, the most extensively used plant model system, thanks to their evolutionary proximity. Methods: To identify the contribution of these transcription factors (TFs) to the root radial growth, we cloned four representative TFs from total RNA isolated from 14 day-old wild type Arabidopsis roots. To get a better picture of how these TFs function, we developed constructs that would modify TFs into either activators or repressors. These constructs were then mobilized into both Arabidopsis and radish plants using the Agrobacterium. Transgenic plants will be subjected to various cytological and microscopic analyses to identify possible alteration in cambium function and radial growth. Results: From this study, we hope to discover whether the same set of TFs controls cambium activities in Arabidopsis and radish. Moreover, we hope to learn how radial growth is regulated in radish. If this strategy is fruitful, then the same approach can be applied to engineer other root crops. Conclusion: We anticipate that a better understanding of these TFs and their role in cambium functions and radial growth holds great merit for plant research.