Genes Are Up-regulated by Environmental Cues That Promote Flowering.

Like , the flowering of the legume is promoted by long day (LD) photoperiod and vernalization. However, there are differences in the molecular mechanisms involved, with orthologs of two key regulators, () and (), being absent or not having a role in flowering time function in . In , the MADS-box transcription factor gene, (), plays a key role in integrating the photoperiodic and vernalization pathways. In this study, we set out to investigate whether the genes play a role in regulating flowering time. Three genes were identified and characterized (). All three genes, when heterologously expressed, were able to promote earlier flowering of the late-flowering mutant. The three genes have different patterns of expression. However, consistent with a potential role in flowering time regulation, all three genes are expressed in the shoot apex and are up-regulated in the shoot apex of plants in response to LD photoperiods and vernalization. The up-regulation of genes was reduced in mutants, indicating that they are downstream of Insertion mutant alleles of do not flower late, suggestive of functional redundancy among genes in promoting flowering.