The floral initiation process in soybean.

<p><b>A.</b> An overview of short-day responsive processes in leaf and SAM of soybean. Functional groups of transcripts largely up- or down- regulated are depicted schematically as red or green boxes, respectively while those containing both up- or down-regulated sequences are represented in yellow box. A complete list of Mapman significantly enriched functional categories is given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065319#pone.0065319.s003" target="_blank">Table S2</a>. <b>B.</b> A hypothetical model illustrating potential molecular events underlying the floral initiation process in soybean with an emphasis on hormonal regulation. The model shows the action of auxin, cytokinin (CK) and GA in concert with other known factors (described in Results and Discussion) in regulating the developmental transition in soybean. In particular, GA and CK may form part of the systemic signals in addition to FT. The induction of CKX possibly via auxin to breakdown cytokinin is likely to create a low cytokinin and high GA environment triggering the conversion of SAM to inflorescence meristem.