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The evolutionary origin of the angiosperms (f lowering plants sensu stricto) is still enigmatic. Answers to the question of angiosperm origins are intimately connected to the identification of their sister group among extinct and extant taxa. Most phylogenetic analyses based on morphological data agree that among the groups of extant seed plants, the gnetophytes are the sister group of the angiosperms. According to this view, angiosperms and gnetophytes are the only extant members of a clade called ''anthophytes'' to emphasize their shared possession of f lower-like reproductive structures. However, most phylogeny reconstructions based on molecular data so far did not support an anthophyte clade, but also could not clarify the case because support for alternative groupings has been weak or controversial. We have isolated 13 different homologs of MADS-type f loral homeotic genes from the gnetophyte Gnetum gnemon. Five of these genes fall into monophyletic gene clades also comprising putatively orthologous genes from f lowering plants and conifers, among them orthologs of f loral homeotic B and C function genes. Within these clades the Gnetum genes always form distinct subclades together with the respective conifer genes, to the exclusion of the angiosperm genes. This provides strong molecular evidence for a sister-group relationship between gnetophytes and conifers, which is in contradiction to widely accepted interpretations of morphological data for almost a century. Our phylogeny reconstructions and the outcome of expression studies suggest that complex features such as f lower-like reproductive structures and double-fertilization arose independently in gnetophytes and angiosperms.

Multimorbidity is a health issue mostly dealt with in primary care practice. As a result of their generalist and patient-centered approach, long-lasting relationships with patients, and responsibility for continuity and coordination of care, family physicians are particularly well placed to manage patients with multimorbidity. However, conflicts arising from the application of multiple disease oriented guidelines and the burden of diseases and treatments often make consultations challenging. To provide orientation in decision making in multimorbidity during primary care consultations, we developed guiding principles and named them after the Greek mythological figure Ariadne. For this purpose, we convened a two-day expert workshop accompanied by an international symposium in October 2012 in Frankfurt, Germany. Against the background of the current state of knowledge presented and discussed at the symposium, 19 experts from North America, Europe, and Australia identified the key issues of concern in the management of multimorbidity in primary care in panel and small group sessions and agreed upon making use of formal and informal consensus methods. The proposed preliminary principles were refined during a multistage feedback process and discussed using a case example. The sharing of realistic treatment goals by physicians and patients is at the core of the Ariadne principles. These result from i) a thorough interaction assessment of the patient’s conditions, treatments, constitution, and context; ii) the prioritization of health problems that take into account the patient’s preferences – his or her most and least desired outcomes; and iii) individualized management realizes the best options of care in diagnostics, treatment, and prevention to achieve the goals. Goal attainment is followed-up in accordance with a re-assessment in planned visits. The occurrence of new or changed conditions, such as an increase in severity, or a changed context may trigger the (re-)start of the process. Further work is needed on the implementation of the formulated principles, but they were recognized and appreciated as important by family physicians and primary care researchers.Please see related article: http://www.biomedcentral.com/1741-7015/12/222.Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-014-0223-1) contains supplementary material, which is available to authorized users.

The MADS-box gene AGAMOUS (AG) plays a key role in determining floral meristem and organ identities. We identified three AG homologs, EScaAG1, EScaAG2, and EScaAGL11 from the basal eudicot Eschscholzia californica (California poppy). Phylogenetic analyses indicate that EScaAG1 and EScaAG2 are recent paralogs within the AG clade, independent of the duplication in ancestral core eudicots that gave rise to the euAG and PLENA (PLE) orthologs. EScaAGL11 is basal to core eudicot AGL11 orthologs in a clade representing an older duplication event after the divergence of the angiosperm and gymnosperm lineages. Detailed in situ hybridization experiments show that expression of EScaAG1 and EScaAG2 is similar to AG; however, both genes appear to be expressed earlier in floral development than described in the core eudicots. A thorough examination of available expression and functional data in a phylogenetic context for members of the AG and AGL11 clades reveals that gene expression has been quite variable throughout the evolutionary history of the AG subfamily and that ovule-specific expression might have evolved more than twice. Although sub- and neofunctionalization are inferred to have occurred following gene duplication, functional divergence among orthologs is evident, as is convergence, among paralogs sampled from different species. We propose that retention of multiple AG homologs in several paralogous lineages can be explained by the conservation of ancestral protein activity combined with evolutionarily labile regulation of expression in the AG and AGL11 clades such that the collective functions of the AG subfamily in stamen and carpel development are maintained following gene duplication.

Virtually all plants show a certain degree of variation among individual metamers during ontogeny. In some cases, however, there are abrupt and substantial changes in form and function (e.g. in leaf form, leaf size, phyllotaxy, internode length, anthocyanin pigmentation, rooting ability, or wood structure). These plants were called "heteroblastic" by Karl Goebel more than a century ago, but the functional significance of this type of ontogenetic change, the evolutionary trajectories in different plant groups, even their frequency in the plant kingdom are still unresolved issues. We argue that slow progress is partly due to an on-going terminological confusion and the lack of distinction between other developmental processes such as ontogenetic drift. This review develops a conceptual framework for future scientific work, proposes a quantitative index of heteroblasty, and discusses the evidence for developmental regulation, functional significance, and evolutionary implications of heteroblasty to provide a stimulating basis for further research with this fascinating group of plants.Zusammenfassung Fast alle Pflanzen zeigen während der Individualentwicklung ein gewisses Maß an Variabilität einzelner Metamere. Bei manchen Arten kommt es jedoch zu einer ausgeprägten und sprunghaften Änderung in Form und Funktion (z.B. in Blattform oder -stellung, Internodienlänge, Pigmentierung, Holzstruktur, oder hinsichtlich der Fähigkeit zur Bildung von Adventivwurzeln). Obwohl diese Arten von Karl Goebel schon vor mehr als einem Jahrhundert als "heteroblastisch" beschrieben wurden, sind die funktionelle Bedeutung des Phänomens, dessen Evolution innerhalb einzelner Pflanzengruppen, wie auch die Häufigkeit im Pflanzenreich immer noch weitgehend ungeklärt. Dieser schleppende Fortschritt mag mit einem weit verbreiteten terminologischen Durcheinander und dem Fehlen einer klaren Abgrenzung von anderen Entwicklungsprozessen wie der "ontogenetischen Drift" zusammenhängen. Unser Übersichtsartikel entwickelt einen klaren konzeptionellen Rahmen, um eine Basis zu schaffen für zukünftige Forschungsarbeiten dieses faszinierenden Entwicklungsphänomens. Dazu schlagen wir einen quantitativen Index der Heteroblastie vor, skizzieren den gegenwärtigen Wissens- Bot. Rev. (2011) 77:109-151

The Brassicaceae, including Arabidopsis thaliana and Brassica crops, is unmatched among plants in its wealth of genomic and functional molecular data and has long served as a model for understanding gene, genome, and trait evolution. However, genome information from a phylogenetic outgroup that is essential for inferring directionality of evolutionary change has been lacking. We therefore sequenced the genome of the spider flower (Tarenaya hassleriana) from the Brassicaceae sister family, the Cleomaceae. By comparative analysis of the two lineages, we show that genome evolution following ancient polyploidy and gene duplication events affect reproductively important traits. We found an ancient genome triplication in Tarenaya (Th-a) that is independent of the Brassicaceae-specific duplication (At-a) and nested Brassica (Br-a) triplication. To showcase the potential of sister lineage genome analysis, we investigated the state of floral developmental genes and show Brassica retains twice as many floral MADS (for MINICHROMOSOME MAINTENANCE1, AGAMOUS, DEFICIENS and SERUM RESPONSE FACTOR) genes as Tarenaya that likely contribute to morphological diversity in Brassica. We also performed synteny analysis of gene families that confer self-incompatibility in Brassicaceae and found that the critical SERINE RECEPTOR KINASE receptor gene is derived from a lineage-specific tandem duplication. The T. hassleriana genome will facilitate future research toward elucidating the evolutionary history of Brassicaceae genomes.