title: Leaf-Like Sepals Induced by Ectopic Expression of aSHORT VEGETATIVE PHASE(SVP)-Like MADS-Box Gene from the Basal EudicotEpimedium sagittatum.
abstract: EpimediumL. (Berberidaceae, Ranales), a perennial traditional Chinese medicinal herb, has become a new popular landscape plant for ground cover and pot culture in many countries based on its excellent ornamental characteristics and, distinctive and diverse floral morphology. However, little is known about the molecular genetics of flower development inEpimedium sagittatum. Here, we describe the characterization ofEsSVPthat encodes a protein sharing 68, 54, and 35% similarity with SVP, AGAMOUS-like 24 (AGL24) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) inArabidopsis, respectively. Quantitative RT-PCR (qRT-PCR) indicated thatEsSVPtranscripts were principally found in petiole and leaf tissues, with little expression in roots and flowers and no in fruits. The highestEsSVPexpression was observed in leaves. The flowering time of35S::EsSVPin mostArabidopsis thalianaand in all petunia plants was not affected in both photoperiod conditions, but35S::EsSVP5# and35S::EsSVP1#Arabidopsislines induced late and early flowering under long day (LD, 14 h light/10 h dark) and short day (SD, 10 h light/14 h dark) conditions, respectively. The35S::EsSVP Arabidopsisproduced extra secondary inflorescence or floral meristems in the axils of the leaf-like sepals with excrescent trichomes, and leaf-like sepals not able to enclose the inner three whorls completely. Moreover, almost all transgenicArabidopsisplants showed persistent sepals around the completely matured fruits. Upon ectopic expression of35S::EsSVPinPetuniaW115, sepals were enlarged, sometimes to the size of leaves; corollas were greenish and did not fully open. These results suggest thatEsSVPis involved in inflorescence meristem identity and flowering time regulation in some conditions. Although, the SVP homologs might have suffered functional diversification among diverse species between core and basal eudicots, the protein functions are conserved betweenArabidopsis/PetuniaandEpimedium.
authors.affiliation: Chongqing Engineering Research Center for Floriculture, Key Laboratory of Horticulture Science for Southern Mountainous Regions of Ministry of Education, College of Horticulture and Landscape Achitecture, Southwest University Chongqing, China.
authors.forename: Zhineng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, The Chinese Academy of Sciences Guangzhou, China.
authors.forename: Shaohua
authors.initials: S
authors.lastname: Zeng
authors.affiliation: Institute for Molecular Cell Biology, Graduate School of Experimental Plant Sciences, Vrije Universiteit Amsterdam Amsterdam, Netherlands.
authors.forename: Yanbang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Chongqing Engineering Research Center for Floriculture, Key Laboratory of Horticulture Science for Southern Mountainous Regions of Ministry of Education, College of Horticulture and Landscape Achitecture, Southwest University Chongqing, China.
authors.forename: Mingyang
authors.initials: M
authors.lastname: Li
authors.affiliation: Institute for Molecular Cell Biology, Graduate School of Experimental Plant Sciences, Vrije Universiteit Amsterdam Amsterdam, Netherlands.
authors.forename: Erik
authors.initials: E
authors.lastname: Souer
keywords: Epimedium sagittatum; SVP; floral reversion; floral transition; leaf-like sepal