Genome sequence of the metazoan plant-parasitic nematode Meloidogyne incognita

Plant-parasitic nematodes are major agricultural pests worldwide and novel approaches to control them are sorely needed. We report the draft genome sequence of the root-knot nematode Meloidogyne incognita, a biotrophic parasite of many crops, including tomato, cotton and coffee. Most of the assembled sequence of this asexually reproducing nematode, totaling 86 Mb, exists in pairs of homologous but divergent segments. This suggests that ancient allelic regions in M. incognita are evolving toward effective haploidy, permitting new mechanisms of adaptation. The number and diversity of plant cell wall-degrading enzymes in M. incognita is unprecedented in any animal for which a genome sequence is available, and may derive from multiple horizontal gene transfers from bacterial sources. Our results provide insights into the adaptations required by metazoans to successfully parasitize immunocompetent plants, and open the way for discovering new antiparasitic strategies.

Home Is Where the Self Is: Monodrama, Journey-Play Structure, and the Modernist Fairy Tale

The first decade of the twentieth century witnessed the creation of two of the most beloved works of children’s literature ever produced. L. Frank Baum’s 1900 novel The Wizard of Oz and Maurice Maeterlinck’s 1908 play each gave rise to many adaptations, including, well beloved film versions, and both have become a deeply ingrained part of the cultural memory and construction of childhood in both Europe and the United States. And while these works are deeply original in content and detail, the structure of these works harkens back to the form of the journey play (traceable, on some level, back to the medieval morality play Everyman), a form that had undergone a considerable revival in the second half of the nineteenth century in the work of writers such as Henrik Ibsen and August Strindberg. This article explores the structural and conceptual links between Baum and Maeterlinck’s children’s classics, Ibsen’s Norwegian folk play Peer Gynt, and August Strindberg’s Lucky Per’s Journey and The Road to Damascus, Part I. In these works, the protagonists, disenchanted with their homes or current situations, set out on an epic journey in which they come upon characters and situations that act as commentary upon their situations before the journey. Ultimately, the characters return to where they started, with the journey seeming to have been a dream or merely a pointless excursion. But in these journeys of self-discovery, the protagonist that emerges at the end has undergone a significant transformation, a process at the heart of all of these works.

Schizophrenia risk from complex variation of complement component 4

Schizophrenia is a heritable brain illness with unknown pathogenic mechanisms. Schizophrenia's strongest genetic association at a population level involves variation in the major histocompatibility complex (MHC) locus, but the genes and molecular mechanisms accounting for this have been challenging to identify. Here we show that this association arises in part from many structurally diverse alleles of the complement component 4 (C4) genes. We found that these alleles generated widely varying levels of C4A and C4B expression in the brain, with each common C4 allele associating with schizophrenia in proportion to its tendency to generate greater expression of C4A. Human C4 protein localized to neuronal synapses, dendrites, axons, and cell bodies. In mice, C4 mediated synapse elimination during postnatal development. These results implicate excessive complement activity in the development of schizophrenia and may help explain the reduced numbers of synapses in the brains of individuals with schizophrenia.