Molecular regulation of flower development.

Over the past three decades, several hundred genes with important regulatory functions during reproductive development in angiosperms have been identified. While we do not yet know, in most cases, how these genes and their products act, fundamental insights into the molecular mechanisms underlying the formation of flowers have been obtained in recent years. These advances were made possible to a large extent by studying the functions of master regulators of flower development through a multitude of experimental approaches, ranging from basic genetic analysis to genome-wide surveys. Based on the results of this work, several models for the molecular control of flower formation have been proposed, which have been tested and largely validated. These models have guided and informed research in the field, and facilitated recent efforts to delineate the composition and architecture of the gene regulatory networks underlying flower development. In this chapter, we aim to describe the current state of flowering research with a focus on recent progress in the field. We also discuss open questions that we believe need to be addressed in the future to further our understanding of the regulatory mechanisms that control floral morphogenesis and evolution.