Divergent genetic mechanisms underlie reversals to radial floral symmetry from diverse zygomorphic flowered ancestors

Malpighiaceae possess flowers with a unique bilateral symmetry (zygomorphy), which is a hypothesized adaptation associated with specialization on neotropical oil bee pollinators. Gene expression of two representatives of the CYC2 lineage of floral symmetry TCP genes, CYC2A and CYC2B, demarcate the adaxial (dorsal) region of the flower in the characteristic zygomorphic flowers of most Malpighiaceae. Several clades within the family, however, have independently lost their specialized oil bee pollinators and reverted to radial flowers (actinomorphy) like their ancestors. Here, we investigate CYC2 expression associated with four independent reversals to actinomorphy. We demonstrate that these reversals are always associated with alteration of the highly conserved CYC2 expression pattern observed in most New World (NW) Malpighiaceae. In NW Lasiocarpus and Old World (OW) Microsteria, the expression of CYC2-like genes has expanded to include the ventral region of the corolla. Thus, the pattern of gene expression in these species has become radialized, which is comparable to what has been reported in the radial flowered legume clade Cadia. In striking contrast, in NW Psychopterys and OW Sphedamnocarpus, CYC2-like expression is entirely absent or at barely detectable levels. This is more similar to the pattern of CYC2 expression observed in radial flowered Arabidopsis. These results collectively indicate that, regardless of geographic distribution, reversals to similar floral phenotypes in this large tropical angiosperm clade have evolved via different genetic changes from an otherwise highly conserved developmental program

Trajetórias Familiares e Práticas de Gestão: Estudo de Caso da Família Gotardo em Guarapari.

Inserido em uma perspectiva subjetiva de pesquisa sobre empresas familiares, este trabalho, busca somar-se ao o esforço para interpretação de dinâmicas sócio-culturais, contrapondo-se aos que tratam apenas assuntos referentes à sucessão. A pesquisa tem caráter qualitativo e investiga como as práticas sócio-culturais de gestão da família Gotardo configuraram as suas trajetórias empresariais. Para tal, utiliza como procedimento metodológico à análise da história oral desenvolvida sobre a transcrição de entrevistas com os gestores de empresas pertencentes à referida família, em Guarapari-ES. O referencial teórico é desenvolvido em temáticas essenciais para direcionar a pesquisa: gestão como prática social; estudos sobre empresas familiares e trajetórias empresariais e; estudos sobre famílias.Inserted in a subjective perspective of research on family companies, this work search to add to the effort for interpretation of partner-cultural dynamics, opposing to the that just treat referring subjects about the succession. The research has qualitative character and investigates as the social practices of the Gotardo family set its businesses trajectory. For such, it uses as methodological procedure the analysis of the oral history developed about the transcription of interviews with the managers of the companies that belong the referred family in Guarapari-ES. The theoretical thought is developed in essential thematic to set the research: management as social practice; studies on family companies; managerial paths and studies on families

Resolving the backbone of the Brassicaceae phylogeny for investigating trait diversity

Summary: The Brassicaceae family comprises c. 4000 species including economically important crops and the model plant Arabidopsis thaliana. Despite their importance, the relationships among major lineages in the family remain unresolved, hampering comparative research. Here, we inferred a Brassicaceae phylogeny using newly generated targeted enrichment sequence data of 1827 exons (> 940 000 bases) representing 63 species, as well as sequenced genome data of 16 species, together representing 50 of the 52 currently recognized Brassicaceae tribes. A third of the samples were derived from herbarium material, facilitating broad taxonomic coverage of the family. Six major clades formed successive sister groups to the rest of Brassicaceae. We also recovered strong support for novel relationships among tribes, and resolved the position of 16 taxa previously not assigned to a tribe. The broad utility of these phylogenetic results is illustrated through a comparative investigation of genome‐wide expression signatures that distinguish simple from complex leaves in Brassicaceae. Our study provides an easily extendable dataset for further advances in Brassicaceae systematics and a timely higher‐level phylogenetic framework for a wide range of comparative studies of multiple traits in an intensively investigated group of plants

Vision, challenges and opportunities for a Plant Cell Atlas

With growing populations and pressing environmental problems, future economies will be increasingly plant-based. Now is the time to reimagine plant science as a critical component of fundamental science, agriculture, environmental stewardship, energy, technology and healthcare. This effort requires a conceptual and technological framework to identify and map all cell types, and to comprehensively annotate the localization and organization of molecules at cellular and tissue levels. This framework, called the Plant Cell Atlas (PCA), will be critical for understanding and engineering plant development, physiology and environmental responses. A workshop was convened to discuss the purpose and utility of such an initiative, resulting in a roadmap that acknowledges the current knowledge gaps and technical challenges, and underscores how the PCA initiative can help to overcome them.</jats:p

Structure and development of Rafflesiaceae

Rafflesiaceae produce the largest flowers among all flowering plants, measuring up to a meter in diameter and weighting 7 kg, and have been a source of amazement since their discovery about two centuries ago. In addition to producing the world's largest flowers, Rafflesiaceae are obligate holoparasites, residing inside their vine hosts vegetatively and emerging out only during flowering. Despite their record- breaking status and iconic significance for the conservation of the tropical rainforest, remarkably little is known about these fascinating plants, due to their remote habitat, rarity, and our inability to cultivate them. The goal of my dissertation is to provide an integrated picture of the vegetative and reproductive morphology of Rafflesiaceae

Using mustard genomes to explore the genetic basis of evolutionary change.

Recent advances in sequencing technologies and gene manipulation tools have driven mustard species into the spotlight of comparative research and have offered powerful insight how phenotypic space is explored during evolution. Evidence emerged for genome-wide signal of transcription factors and gene duplication contributing to trait divergence, e.g., PLETHORA5/7 in leaf complexity. Trait divergence is often manifested in differential expression due to cis-regulatory divergence, as in KNOX genes and REDUCED COMPLEXITY, and can be coupled with protein divergence. Fruit shape in Capsella rubella results from anisotropic growth during three distinct phases. Brassicaceae exhibit novel fruit dispersal strategy, explosive pod shatter, where the rapid movement depends on slow build-up of tension and its rapid release facilitated by asymmetric cell wall thickenings

Interspecies gene transfer as a method for understanding the genetic basis for evolutionary change: Progress, Pitfalls and Prospects

The recent revolution in high throughput sequencing and associated applications provides excellent opportunities to catalogue variation in DNA sequences and gene expression between species. However, understanding the astonishing diversity of the Tree of Life requires understanding the phenotypic consequences of such variation and identification of those rare genetic changes that are causal to diversity. One way to study the genetic basis for trait diversity is to apply a transgenic approach and introduce genes of interest from a donor into a recipient species. Such interspecies gene transfer (IGT) is based on the premise that if a gene is causal to the morphological divergence of the two species, the transfer will endow the recipient with properties of the donor. Extensions of this approach further allow identifying novel loci for the diversification of form and investigating cis- and trans-contributions to morphological evolution. Here we review recent examples from both plant and animal systems that have employed IGT to provide insight into the genetic basis of evolutionary change. We outline the practice of IGT, its methodological strengths and weaknesses, and consider guidelines for its application, emphasizing the importance of phylogenetic distance, character polarity, and life history. We also discuss future perspectives for exploiting IGT in the context of expanding genomic resources in emerging experimental systems and advances in genome editing