Abstract

Flowering, the predominant reproductive strategy in the plant life cycle, is an intricate process regulated by both genetic and environmental factors. In Gossypium hirsutum , flowering time significantly influences adaptation and yield. Here, we identify the transcription factor GhCIL1 as a pivotal regulator promoting flowering in this crucial crop. Overexpression of GhCIL1 presented significantly shorter bolting and flowering time in Arabidopsis thaliana , while the silencing of GhCIL1 in cotton has been shown to delay bud appearance and flowering. Through the joint analysis of transcriptome based on the OE- GhCIL1 and CR- GhCIL1 , it was found that GhCIL1 may regulate GhSWEET15-D04 , GhSWEET15-A04 and GhPRR5 . Electrophoretic mobility shift assays (EMSAs) and Dual-luciferase assays demonstrated that GhCIL1 could directly bind to and promote the expression of GhSWEET15-D04 , GhSWEET15-A04 , GhPRR5 , and GhFT . The GhCIL1 possesses the capacity to form homodimers independently or heterodimers in conjunction with GhPRE6. silencing of GhPRE6 in cotton has been shown to promote bud appearance and flowering. Dual-luciferase assays and EMSAs demonstrated that the cotransformation of GhCIL1 and GhPRE6 inhibited the promotion and binding effect of GhCIL1 on GhSWEET15-D04 , GhSWEET15-A04 , GhPRR5 , and GhFT . In conclusion, our work unveils a novel the flowering regulation pathway in cotton.