Two FD homologs from London plane (Platanus acerifolia) are associated with floral initiation and flower morphology

• Published in: Plant science (Limerick) Vol. 310; p. 110971
• Main Authors: Cai, Fangfang, Shao, Changsheng, Zhang, Yanping, Shi, Gehui, Bao, Zhiru, Bao, Manzhu, Zhang, Jiaqi
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.09.2021
• Subjects: Alternative splicing; Alternative Splicing - genetics; Alternative Splicing - physiology; Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Floral development; Floral transition; flower morphology; FLOWERING LOCUS T (FT); Flowers - genetics; Flowers - metabolism; Flowers - physiology; Gene Expression Regulation, Plant; genes; loci; Nicotiana - genetics; Nicotiana - metabolism; Nicotiana tabacum; Plant Proteins - genetics; Plant Proteins - metabolism; Platanus acerifolia; tobacco; transcription factors; FLOWERING LOCUS T (FT); Alternative splicing; Platanus acerifolia; Nicotiana tabacum; Floral transition; FD; Floral development
• ISSN: 0168-9452; 1873-2259; 1873-2259
• DOI: 10.1016/j.plantsci.2021.110971

•PaFDL1 and PaFDL2 undergo post-transcriptional alternative splicing, each gene produces two transcript forms.•PaFDL1 and PaFDL2 are expressed in the stems and subpetiolar buds, and may play conserved functions in floral induction.•The PaFDL1-I and PaFDL2-I proteins may interact with PaFT and PaFTL in order to participate in floral development. The flowering-time gene FD encodes a bZIP transcription factor that interacts with FLOWERING LOCUS T (FT) to induce flowering in Arabidopsis. Previous research has identified two FT homologs of Platanus acerifolia, PaFT and PaFTL, which each have different expression patterns and are involved in diverse developmental processes. However, it is not known whether such FT/FD complexes participate in the flowering processes in P. acerifolia. Therefore, we isolated two closely related FD homologs, PaFDL1 and PaFDL2, and investigated their functions through the analysis of expression profiles, transgenic phenotypes, their interactions with different FT proteins, and potential cis-regulatory elements in their promoters. The PaFDL genes were found to display their maximal expression levels during the stage of floral transition, and subsequent expression patterns were also seen to be related to inflorescence developmental stage. In addition, both PaFDL1 and PaFDL2 were found to be subject to post-transcriptional alternative splicing, each gene producing two transcript forms. Transgenic tobacco overexpressing each of the four resulting transcript types displayed accelerated floral initiation and produced abnormal flowers. The results suggested that the complete PaFDL proteins may interact with different PaFT/PaFTL proteins in order to fulfill both conservative and diverse functions in floral initiation and floral development.