Description
Aristolochia fimbriata is a member of an early diverging lineage of flowering plants and a promising candidate for evo-devo studies. Aristolochia flowers exhibit a unique floral synorganization that consists of a petaloid sepal-derived perianth, no petals, and a congenital fusion of stamens and carpels into a gynostemium. We investigated the floral development and morphology of A. fimbriata, and evaluated the expression of key regulatory MADS-box genes that are likely responsible for the identity of perianth and gynostemium. MADS-box ABCDE gene homologs were isolated and were included in phylogenetic analyses to confirm their placement as pre-duplication genes prior to the γ polyploidization event occurring in core-eudicots. Additionally, RT-PCR and in situ hybridization were performed to identify gene expression patterns and hypothesize gene functions. AfimFUL and AfimAG show broad expression patterns in all floral organs leaves and fruits, contrary to the canonical mutually exclusive expression patterns shown by the orthologs (A and C class genes) in the model eudicot Arabidopsis thaliana in sterile and fertile floral whorls, respectively. B-class genes, AfimAP3 and AfimPI are broadly expressed early on throughout the flower but become restricted to the distal portion of the perianth at anthesis. The D class gene AfimSTK is only turned on in the gynostemium and the ovary. Finally, AfimAGL6 shows a restricted expression pattern to the perianth. Our results suggest that the ABCDE model can be partially extrapolated to early diverging angiosperms and postulates AGL6 as a candidate gene for sepal identity in Aristolochia.| Period | 06 Aug 2015 |
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| Event title | Pan-American Society for Evolutionary Developmental Biology |
| Event type | Other |
| Location | Berkley, United States, CaliforniaShow on map |