The ABC Model and its Applicability to Basal Angiosperms
Open Access
- 6 July 2007
- journal article
- review article
- Published by Oxford University Press (OUP) in Annals of Botany
- Vol. 100 (2), 155-163
- https://doi.org/10.1093/aob/mcm117
Abstract
Although the flower is the central feature of the angiosperms, little is known of its origin and subsequent diversification. The ABC model has long been the unifying paradigm for floral developmental genetics, but it is based on phylogenetically derived eudicot models. Synergistic research involving phylogenetics, classical developmental studies, genomics and developmental genetics has afforded valuable new insights into floral evolution in general, and the early flower in particular. Genomic studies indicate that basal angiosperms, and by inference the earliest angiosperms, had a rich tool kit of floral genes. Homologues of the ABCE floral organ identity genes are also present in basal angiosperm lineages; however, C-, E- and particularly B-function genes are more broadly expressed in basal lineages. There is no single model of floral organ identity that applies to all angiosperms; there are multiple models that apply depending on the phylogenetic position and floral structure of the group in question. The classic ABC (or ABCE) model may work well for most eudicots. However, modifications are needed for basal eudicots and, the focus of this paper, basal angiosperms. We offer ‘fading borders’ as a testable hypothesis for the basal-most angiosperms and, by inference, perhaps some of the earliest (now extinct) angiosperms.Keywords
This publication has 50 references indexed in Scilit:
- Genetic Footprints of Stamen Ancestors Guide Perianth Evolution inPersea(Lauraceae)International Journal of Plant Sciences, 2006
- Molecular and Phylogenetic Analyses of the MADS-Box Gene Family in TomatoMolecular Biology and Evolution, 2006
- Phylogeny and Domain Evolution in the APETALA2-like Gene FamilyMolecular Biology and Evolution, 2005
- Expression of floral MADS‐box genes in basal angiosperms: implications for the evolution of floral regulatorsThe Plant Journal, 2005
- Evolution of the APETALA3 and PISTILLATA Lineages of MADS-Box–Containing Genes in the Basal AngiospermsMolecular Biology and Evolution, 2004
- Patterns of Gene Duplication and Functional Evolution During the Diversification of theAGAMOUSSubfamily of MADS Box Genes in AngiospermsGenetics, 2004
- Evolution of the Petal and Stamen Developmental Programs: Evidence from Comparative Studies of the Lower Eudicots and Basal AngiospermsInternational Journal of Plant Sciences, 2000
- The petunia MADS box gene FBP11 determines ovule identity.THE PLANT CELL ONLINE, 1995
- The war of the whorls: genetic interactions controlling flower developmentNature, 1991
- Genetic Control of Flower Development by Homeotic Genes in Antirrhinum majusScience, 1990