Flowering is one of the major developmental commitments in the plant life cycle. Plants have evolved intricate regulatory networks to control flowering time in response to changing environmental conditions. Two major environment cues that plants use to sense seasonal changes are temperature (i.e. winter) and day length (i.e. photoperiod). In the model plant, Arabidopsis thaliana, the VERNALIZATION INSENSITIVE 3 (VIN3) gene family mediates environmental cues to regulate flowering time through a group of floral repressors including the FLOWERING LOCUS C (FLC) gene family. This project will use biochemical and genetic approaches to dissect the molecular mechanisms that control flowering time through these two gene families. Proteins in the VIN3 gene family mediate histone modifications on target chromatin. Chromatin-based gene regulation is a major regulatory theme in eukaryotic gene regulation. Thus, the results of this project will be of interest to a broad scientific community. Furthermore, the environmentally regulated nature of the VIN3 gene family regulatory network will provide a unique opportunity to study the effect of environmental inputs on the epigenetic regulation of gene expression. Flowering time control also has a potential to be used in agricultural applications, as many crops flower in response to environmental changes. This work may provide new methods to improve crop productivity. Proposed research will provide an ample opportunity to train a postdoctoral fellow and a graduate student. This proposal will also provide undergraduate students and K-12 students with hands-on experience in the research laboratory.
Flowering is one of the major developmental commitments in the plant life cycle. Flowering time control also has a potential to be used in agricultural applications, as many crops flower in response to environmental changes. It is essential to understand how flowering time is regulated under changing environmental conditions. To address the fundamental mechanisms of flowering time regulation, we used a model plant Arabidopsis. For last several decades, molecular genetic studies in Arabidopsis have shed light on the molecular mechanism of flowering time control. In this project, we revealed that the VIN3 gene family mediates environmental cues to regulate flowering time through a group of floral repressors including the FLC gene family. Two major environment cues that plants use to sense seasonal changes are temperature (i.e. winter) and day length (i.e. photoperiod response). The regulatory network in which the VIN3 gene family operates in response to such environmental cues and includes multiple layers of gene regulation including chromatin modifications. In particular, there are specific regulatory relationships between VIN3 and FLC gene family members under different environmental conditions. Therefore, our study also provided a paradigm for environmental epigenetic regulation. In addition, this project has provided future-generation scientists (including underrepresented group of students) with an ample opportunity of training in modern molecular genetic techniques.
