FUNCTIONAL CHARACTERIZATION OF DOTFL1 IN DENDROBIUM CHAO PRAYA SMILE

Abstract

Understanding of the molecular mechanisms of the floral transition and inflorescence development in Dendrobium orchids is not only important for gaining insights into reproductive biology of orchids, but also necessary for exploring new gene resources for orchid breeding. Here we demonstrate that DOTFL1 regulates floral transition and inflorescence development in Dendrobium Chao Praya Smile. Overexpression of DOTFL1 in Dendrobium orchids and Arabidopsis results in late flowering as well as leafy flowers and flowers without petals. 35S:RNAi-DOTFL1 transgenic orchids show early flowering. Furthermore, the dotfl1 orchid mutants generated by the CRISPR/Cas9 system display early flowering and generate multiple shoots with tiny inflorescences. Interestingly, DOTFL1 also negatively mediates the formation of storage organ, pseudobulb, in Dendrobium orchids. DOSOC1 interacts with DOAGL24 to directly bind to the CArG-box motif at DOTFL1, thereby functioning as the upstream regulators of DOTFL1.