Characterization of CYCLOIDEA-like genes in Phalaenopsis equestris

  • 廖 盈貴

Student thesis: Master's Thesis


The Orchidaceae is one of the most species-rich plant families which are renowned for their spectacular floral diversity To maintain bilateral symmetry of flower is important for orchid flower to attract pollinator Previous studies showed that CYCLOIDEA genes can regulate bilateral symmetry by inhibit cell proliferation CYC genes belong to TCP family which involved in the development of cell In Antirrhium majus CYC gene plays an role on inhibition of the cell proliferation of dorsal petals and stamens In Asteraceae and Gesneriaceae previous study showed that CYC/TB1-like proteins can interact with transcription factors to form homodimer or heterodimer However study on CYC-like genes in monocots is few In this study we identified three CYC-like genes named as PeCYC1 PeCYC2 and PeCYC3 from Phalaenopsis equestris Multiple sequence alignment showed PeCYC proteins contain typical TCP domains and R domain Phylogenetic analysis showed that PeCYC genes belong to class II TCP genes and are closely related to CYC/TB1 genes of monocots rather than eudicots The expression patterns showed that expression of PeCYC1 and PeCYC2 are restricted in lateral sepals labellum and column However expression of PeCYC1 and PeCYC2 were ectopically expressed into lip-like petals of peloric mutant Yeast-two hybrid results showed that PeCYC1 may form homodimer However PeCYC1 lost its homodimer formation activity when R-domain was deleted Furthermore Both PeCYC1 and PeCYC2 has ability to interact with B-class PI-like PeMADS6 protein Overexpression of PeCYC1 in Arabidopsis thaliana showed delayed flowering smaller leaves and flowers and shorter roots compared with those of wild type Scanning Electron Micrographic results showed that the cells of leaves and petals of transgenic plants were smaller than those of wild-type These results will shed light on the roles of CYC/TB1 genes played in floral symmetry of monocot plants
Date of Award2014 Jan 21
Original languageEnglish
SupervisorWen-Chieh Tsai (Supervisor)

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