Stem Cell Signaling During Capitulum Development

Capitulum-type inflorescences are found throughout the sunflower family and are thought to have evolved following the compaction (height) and expansion (width) of a more diffuse flowering shoot. After transition to flowering, most plants will initiate flower development immediately and maintain continuous flower production during inflorescence formation (typical of diverse inflorescence-types such as racemes, thyrses, spikes, etc.). In contrast, capitulum development has a period of prolonged "quiescence" in the inflorescence meristem, when there is little organ proliferation, facilitating the lateral expansion of this tissue prior to flower initiation (Figure 1). The Jones lab is interested in identifying signaling mechanisms that directly contribute to capitulum expansion and developmental timing of floret initiation, centered around understanding the role of conserved stem cell signaling pathways (such as CLAVATA signaling) in regulating meristem expansion.