The cloning, characterization and expression analysis of Flowering Locus T gene from (Prunus armenıaca L.)

In perennial woody plants, the most important morphological transformation is from the vegetative to reproductive phase, which is part of the flowering cycle. The success of this transition guarantees the basis not only for the completion of the life cycle, but also for the production of economically quality fruit and seed. Initiation of flowering in plants is controlled by endogenous and environmental signals like the photoperiod, vernalization, ambient temperature, plant hormone, and autonomous pathways. In plants of economic importance, the molecular mechanism of the photoperiod is the most important key to controlling flowering time. FLOWERING LOCUS T (FT), main actor of photoperiod dependent flowering, encodes protein belonging to the phosphatidylethanolamine-binding protein (PEBP) family and plays important roles in regulating flowering in plants. Prunus armeniaca, belonging to Rosaceae, is one of the most economically important fruit for Turkey. To date, FT gene has been extensively studied for its role in flowering primarily in Arabidopsis and in various species. However, the role of FT is not completely clear on flowering in Prunus armeniaca L. In this Ph.D. thesis, the FT gene was identified for the first time in Prunus armeniaca L. by homology-based cloning and RACE-PCR, and expression analysis was performed at different developmental stages. An open reading frame of 525 bp, translating a protein of 174 amino acids (AAs), was obtained from PaFT. The AA sequence alignment of PaFT indicated that it contains a conserved domain, specific to the PEBP family, and shares high homology with other Prunus FT proteins: 99.4 % of PpFT from Prunus persica, 98.8 % from Prunus mume. Moreover, we showed that FT is expressed in leaves, floral organs, and fruits in Prunus armeniaca L. with RT-qPCR analysis. Our results suggest that PaFT is a homologous gene of FT in apricot and it may function in coordinating plant flowering time.