MOLECULAR MECHANISMS UNDERLYING FLORAL ORGAN PHOTOSYNTHESIS

MADS结构域转录因子AGAMOUS(AG)是拟南芥花生殖器官分化、分化和分生组织决定所必需的。我们的研究小组已经提出证据表明，AG控制光合作用相关基因的表达，包括气孔发育所需的基因。虽然AG在具体化和确定性过程中的作用在真雄蕊中可能是保守的，但在其他真雄蕊中，对AG在分化过程中的需求尚不清楚，其中包括建立角果作为光合器官。为了解决这些问题，我们正在进行A.thaliana和Cardamine hirsuta之间的比较发育和功能基因组学实验，这两个物种在大约3200万年前拥有共同的祖先。我们已经获得了毛冠果和刺参转基因品系，它们可以促进AG活性的可诱导下调，我们将使用它们进行比较转录分析。此外，我们将进行体内蛋白质-DNA结合图谱的比较实验，以确定每个同源基因的靶标。我们将在两个物种的AG活动中断后，用表型评估覆盖这些数据。这项工作将揭示AG的保守和分化活性以及潜在基因调控网络的灵活性。

The MADS-domain transcription factor AGAMOUS (AG) is required for specification, differentiation and meristem determinacy of floral reproductive organs in Arabidopsis thaliana. Our group has generated evidence to indicate that AG controls the expression of photosynthesis related gene expression, including genes required for stomatal development. Although the roles of AG during specification and determinacy are likely conserved in eudicots, the requirement for AG during differentiation, which includes the establishment of the silique as a photosynthetic organ, in other eudicots is unclear. To address these questions, we are performing comparative developmental and functional genomics experiments between A. thaliana and Cardamine hirsuta, which last shared a common ancestor ~32 million years ago. We have generated C. hirsuta and A. thaliana transgenic lines that facilitate an inducible knock-down of AG activity, which we will use to perform comparative transcriptomic assays. In addition, we will perform comparative in vivo protein-DNA binding profiling experiments to identify the targets of each orthologue. We will overlay these data with phenotypic assessments following disruption of AG activity in both species. This work will reveal the conserved and diverged activities of AG and the flexibility of the underlying gene regulatory network.