When rates of transcription from specific genes change, delays of variable length intervene before the corresponding mRNAs and proteins attain new levels. For most mammalian genes, the time required to complete transcription, processing, and transport of mRNA is much shorter than the period needed to achieve a new, steady‐state level of protein. Studies of inducible genes have shown that the period required to attain new levels of individual mRNAs and proteins is related to their unique half‐lives. The basis for this (...) is a physical principle that predicts rates of accumulation of particles in compartmental systems. The minimum period required to achieve a new level is directly proportional to product half‐lives because rates of decay control the ratio between the rate of synthesis and the concentration of gene products at steady state. This kinetic model suggests that sensitivity of gene products to degradation by ribonucleases and proteinases is an important determinant of the time scale of gene expression. (shrink)

Given the pervasiveness of gene sharing in evolution and the extent of homology across the tree of life, why is everything not homologous with everything else? The continuity and overlapping genetic contributions to diverse traits across lineages seem to imply that no discrete determination of homology is possible. Although some argue that the widespread overlap in parts and processes should be acknowledged as “partial” homology, this threatens a broad base of presumed comparative morphological knowledge accepted by most biologists. Following (...) a long scientific tradition, we advocate a strategy of “theoretical articulation” that introduces further distinctions to existing concepts to produce increased contrastive resolution among the labels used to represent biological phenomena. We pursue this strategy by drawing on successful patterns of reasoning from serial homology at the level of gene sequences to generate an enriched characterization of serial homology as a hierarchical, phylogenetic concept. Specifically, we propose that the concept of serial homology should be applied primarily to repeated but developmentally individualized body parts, such as cell types, differentiated body segments, or epidermal appendages. For these characters, a phylogenetic history can be reconstructed, similar to families of paralogous genes, endowing the notion of serial homology with a hierarchical, phylogenetic interpretation. On this basis, we propose a five-fold theoretical classification that permits a more fine-grained mapping of diverse trait-types. This facilitates answering the question of why everything is not homologous with everything else, as well as how novelty is possible given that any new character possesses evolutionary precursors. We illustrate the fecundity of our account by reference to debates over insect wing serial homologs and vertebrate paired appendages. (shrink)

I provide a history of research on G×E in this article, showing that there have actually been two distinct concepts of G×E since the very origins of this research. R. A. Fisher introduced what I call the biometric concept of G×E, or G×EB, while Lancelot Hogben introduced what I call the developmental concept of G×E, or G×ED. Much of the subsequent history of research on G×E has largely consisted in the separate legacies of these separate concepts, along with the (sometimes (...) acrimonious) disputes that have arisen time and again when employers of each have argued over the appropriate way to conceptualize the phenomenon. With this history in place, I then consider more recent attempts to distinguish between different concepts of G×E, paying particular attention to the commonly made distinction between “statistical interaction” and “interactionism,” and also Michael Rutter’s distinction between “statistical interaction” and “the biological concept of interaction.” I argue that the history of the separate legacies of G×EB and G×ED better supports Rutter’s analysis of the situation, and that this analysis best paves the way for an integrative relationship between the various scientists investigating the place of G×E in the etiology of complex traits. (shrink)

Throughout the biological and biomedical sciences there is a growing need for, prescriptive ‘minimum information’ (MI) checklists specifying the key information to include when reporting experimental results are beginning to find favor with experimentalists, analysts, publishers and funders alike. Such checklists aim to ensure that methods, data, analyses and results are described to a level sufficient to support the unambiguous interpretation, sophisticated search, reanalysis and experimental corroboration and reuse of data sets, facilitating the extraction of maximum value from data sets (...) them. However, such ‘minimum information’ MI checklists are usually developed independently by groups working within representatives of particular biologically- or technologically-delineated domains. Consequently, an overview of the full range of checklists can be difficult to establish without intensive searching, and even tracking thetheir individual evolution of single checklists may be a non-trivial exercise. Checklists are also inevitably partially redundant when measured one against another, and where they overlap is far from straightforward. Furthermore, conflicts in scope and arbitrary decisions on wording and sub-structuring make integration difficult. This presents inhibit their use in combination. Overall, these issues present significant difficulties for the users of checklists, especially those in areas such as systems biology, who routinely combine information from multiple biological domains and technology platforms. To address all of the above, we present MIBBI (Minimum Information for Biological and Biomedical Investigations); a web-based communal resource for such checklists, designed to act as a ‘one-stop shop’ for those exploring the range of extant checklist projects, and to foster collaborative, integrative development and ultimately promote gradual integration of checklists. (shrink)

The fact that genes and environment contribute differentially to variation in human behaviors, traits and attitudes is central to the field of behavior genetics. Perceptions about these differential contributions may affect ideas about human agency. We surveyed two independent samples (N = 301 and N = 740) to assess beliefs about free will, determinism, political orientation, and the relative contribution of genes and environment to 21 human traits. We find that lay estimates of genetic influence on these traits cluster into (...) four distinct groups, which differentially predict beliefs about human agency, political orientation, and religiosity. Despite apparent ideological associations with these beliefs, the correspondence between mean lay estimates and published heritability estimates for the surveyed traits is large (r = .77). Belief in genetic determinism emerges as a modest predictor of accuracy in these lay estimates. Additionally, educated mothers with multiple children emerge as particularly accurate in their estimates of the genetic contribution to these traits. (shrink)

An early step in sporulation of the bacterium Bacillus subtilis, is the formation of two compartments in the developing sporangium: the mother cell and the forespore. These compartments differ in their programs of gene expression and developmental fate. The establishment of cell type within this simple developmental program, is accomplished by the compartmentalization of sigma subunits of RNA polymerase. The localization of these sigma factors results in compartment‐specific gene expression. Recent experiments have elucidated some of the early steps (...) in the establishment of 3V cell type. After septum formation, the activity of the sigma factor, σF, is confined to the forespore compartment. This, in turn, results in the localized expression of another developmental sigma factor, σG. The forespore localization of these two sigma factors, establishes the forespore line of gene expression. σF and σG also regulate mother cell events. σF activity in the forespore regulates the proteolytic processing of σE within the mother cell compartment. The localization σE activity leads to mother cell expression of another sigma factor, pro‐σK The proteolytic processing of pro‐σK to mature σK is controlled by the forespore sigma factor, σG Mature σK then directs the transcription of mother cell specific genes. Therefore, the initial localization of σF activity to the forespore compartment, orchestrates the establishment of cell type in both forespore and mother cell compartments. (shrink)

Stolen Legacy by George G.M. James refutes the Euro-centric myth that the origin of Western philosophy is Greek. First published in 1954, this book was seminal in leading to a radical reappraisal of a philosophical system long thought to be of European origin. It is an essential work in the syllabus for the study of Western philosophy.

© 2015, Springer-Verlag Berlin Heidelberg.Genetic studies have identified single nucleotide polymorphisms associated with the risk of prostate cancer. It remains unclear whether such genetic variants are associated with disease aggressiveness. The NCI-SPORE Genetics Working Group retrospectively collected clinicopathologic information and genotype data for 36 SNPs which at the time had been validated to be associated with PC risk from 25,674 cases with PC. Cases were grouped according to race, Gleason score and aggressiveness. Statistical analyses were used to compare the frequency (...) of the SNPs between different disease cohorts. After adjusting for multiple testing, only PC-risk SNP rs2735839 was significantly and inversely associated with aggressive and high-grade disease in European men. Similar associations with aggressive and high-grade disease were documented in African-American subjects. The G allele of rs2735839 was associated with disease aggressiveness even at low PSA levels in both European and African-American men. Our results provide further support that a PC-risk SNP rs2735839 near the KLK3 gene on chromosome 19q13 may be associated with aggressive and high-grade PC. Future prospectively designed, case-case GWAS are needed to identify additional SNPs associated with PC aggressiveness. (shrink)

The Alexandrian emphasis on smallness, elegance, and slightness at the expense of grand themes in major poetic genres was not preciosity for its own sake: although the poetry was written by and for scholars, it had much larger sources than the bibliothecal context in which it was composed. Since the time of the classical poets, much had changed. Earlier Greek poetry was an intimate part of the life of the city-state, written for its religious occasions and performed by its citizens. (...) But eh conquests of Alexander had altered the structure and the boundaries of the Greek world to an astonishing degree. Alexandria, the center of the poetic culture of the new age, was a city that had not even existed at the time of Euripides; it was in Egypt, not in Greece, and was a huge, polyglot community. As immigrants immersed in a new, impersonal, and bureaucratic society, the poets not unreasonably sought out what was small, intimate, and personal in their verses. The heroes of early Greek poetry are larger than life; those of Alexandrian poetry are life-size. They are human, like us; they have a childhood and an old age; they are afraid or in love or caught in a rainstorm. It was simply one way of reducing the world to more manageable dimensions. At the same time, the new world of Alexandria needed a new poetry. To continue writing epics about a mythology that seemed very far away was senseless; it was impossible to recapture either the style or the immediacy of Homer, lyric poetry, or Attic tragedy. The scholar-poets of Alexandria admired the literature of classical Greece; for them Homer was incomparable and inimitable, to be studied—but not to be copied. Far better, then, to find a new voice on a more manageable scale: instead of oral epic, erudite epyllion; instead of lyric, epigram; instead of tragedy, mime. The poets of an urban and unheroic world might long for but could never re-create the grandeur of the past. James E. G. Zetzel is associate professor of classics at Princeton University and editor of the Transactions of the American Philological Association. He is the author of Latin Textual Criticism in Antiquity and, with Anthony T. Grafton and Glenn W. Most, has translated Friedrich August Wolf’s Prolegomena ad Homerum. (shrink)

A multi-method, multi-informant method was used to collect data from diverse stakeholders about school climate to inform school improvement efforts as part of the Positive Behaviour Intervention Supports framework. Teachers, administrators, school staff and students completed surveys and parents participated in focus groups to gather perspectives about school climate. Respondents identified safety as a strength at the school, staff and student results suggested interpersonal relationships as an area for improvement and staff identified parent involvement as an area for growth. Both (...) positive and negative perceptions of school climate emerged from the parent focus group. While there are limitations to the generalisability of the results, this case study provides a useful approach for schools to assess their school climate and establish goals for improvement. (shrink)

In this book James D. G. Dunn explores the nature of the religious experiences that were at the forefront of emerging Christianity.

A central topic in research at the intersection of development and evolution is the origin of novel traits. Despite progress on understanding how developmental mechanisms underlie patterns of diversity in the history of life, the problem of novelty continues to challenge researchers. Here we argue that research on evolutionary novelty and the closely associated phenomenon of co-option can be reframed fruitfully by: (1) specifying a conceptual model of mechanisms that underwrite character identity, (2) providing a richer and more empirically precise (...) notion of co-option that goes beyond common appeals to “deep homology”, and (3) attending to the nature of experimental interventions that can determine whether and how the co-option of identity mechanisms can help to explain novel character origins. This reframing has the potential to channel future investigation to make substantive progress on the problem of evolutionary novelty. To illustrate this potential, we apply our reframing to two case studies: treehopper helmets and beetle horns. (shrink)