Circular RNAs modulate the floral fate acquisition in soybean shoot apical meristem

BackgroundSoybean (Glycine max), a major oilseed and protein source, requires a short-day photoperiod for floral induction. Though key transcription factors controlling flowering have been identified, the role of the non-coding genome is limited. Circular RNAs (circRNAs) recently emerged as a novel class of RNAs with critical regulatory functions. However, a study on circRNAs during the floral transition of a crop plant is lacking. We investigated the expression and potential function of circRNAs in floral fate acquisition by soybean shoot apical meristem in response to short-day treatment.ResultsUsing deep sequencing and in-silico analysis, we denoted 384 circRNAs, with 129 exhibiting short-day treatment-specific expression patterns. We also identified 38 circRNAs with predicted binding sites for miRNAs that could affect the expression of diverse downstream genes through the circRNA-miRNA-mRNA network. Notably, four different circRNAs with potential binding sites for an important microRNA module regulating developmental phase transition in plants, miR156 and miR172, were identified. We also identified circRNAs arising from hormonal signaling pathway genes, especially abscisic acid, and auxin, suggesting an intricate network leading to floral transition.ConclusionsThis study highlights the gene regulatory complexity during the vegetative to reproductive transition and paves the way to unlock floral transition in a crop plant.

Automated summary

This study reveals the expression and function of circular RNAs (circRNAs) in regulating floral development in soybean under short-day treatment. Through deep sequencing and computational analysis, 384 circRNAs were identified, with 129 showing short-day treatment-specific expression patterns. Several circRNAs with potential miRNA binding sites were also found, suggesting their involvement in regulating downstream gene expression through the circRNA-miRNA-mRNA network. Additionally, four different circRNAs with binding sites for important microRNA modules (miR156 and miR172) related to developmental phase transition in plants were identified. This study highlights the complexity of gene regulation during the transition from vegetative to reproductive growth in soybean and provides new insights into floral transition in crop plants.