Developmental Phenomena Research Articles

Driving developmental and evolutionary change: A systems biology view

Embryonic development is underpinned by ∼50 core processes that drive morphogenesis, growth, patterning and differentiation, and each is the functional output of a complex molecular network. Processes are thus the natural and parsimonious link between genotype and phenotype and the obvious focus for any discussion of biological change. Here, the implications of this approach are explored. One is that many features of developmental change can be modeled as mathematical graphs, or sets of connected triplets of the general form <noun><verb><noun>. In these, the verbs (edges) are the outputs of the processes that drive change and the nouns (nodes) are the time-dependent states of biological entities (from molecules to tissues). Such graphs help unpick the multi-level complexity of developmental phenomena and may help suggest new experiments. Another comes from analyzing the effect of mutation that lead to tinkering with the dynamic properties of these processes and to congenital abnormalities; if these changes are both inherited and advantageous, they become evolutionary modifications. In this context, protein networks often represents what classical evolutionary genetics sees as genes, and the realization that traits reflect the output processes of complex networks, particularly for growth, patterning and pigmentation, rather than anything simpler clarifies some problems that the evolutionary synthesis of the 1950s has found hard to solve. In the wider context, most processes are used many times in development and cooperate to produce tissue modules (bones, branching duct systems, muscles etc.). Their underlying generative networks can thus be thought of as genomic modules or subroutines.

Simple Microfluidic Devices for &lt;em&gt;in vivo&lt;/em&gt; Imaging of &lt;em&gt;C. elegans&lt;/em&gt;, &lt;em&gt;Drosophila&lt;/em&gt; and Zebrafish

Micro fabricated fluidic devices provide an accessible micro-environment for in vivo studies on small organisms. Simple fabrication processes are available for microfluidic devices using soft lithography techniques 1-3. Microfluidic devices have been used for sub-cellular imaging 4,5, in vivo laser microsurgery 2,6 and cellular imaging 4,7. In vivo imaging requires immobilization of organisms. This has been achieved using suction 5,8, tapered channels 6,7,9, deformable membranes 2-4,10, suction with additional cooling 5, anesthetic gas 11, temperature sensitive gels 12, cyanoacrylate glue 13 and anesthetics such as levamisole 14,15. Commonly used anesthetics influence synaptic transmission 16,17 and are known to have detrimental effects on sub-cellular neuronal transport 4. In this study we demonstrate a membrane based poly-dimethyl-siloxane (PDMS) device that allows anesthetic free immobilization of intact genetic model organisms such as Caenorhabditis elegans (C. elegans), Drosophila larvae and zebrafish larvae. These model organisms are suitable for in vivo studies in microfluidic devices because of their small diameters and optically transparent or translucent bodies. Body diameters range from ~10 μm to ~800 μm for early larval stages of C. elegans and zebrafish larvae and require microfluidic devices of different sizes to achieve complete immobilization for high resolution time-lapse imaging. These organisms are immobilized using pressure applied by compressed nitrogen gas through a liquid column and imaged using an inverted microscope. Animals released from the trap return to normal locomotion within 10 min. We demonstrate four applications of time-lapse imaging in C. elegans namely, imaging mitochondrial transport in neurons, pre-synaptic vesicle transport in a transport-defective mutant, glutamate receptor transport and Q neuroblast cell division. Data obtained from such movies show that microfluidic immobilization is a useful and accurate means of acquiring in vivo data of cellular and sub-cellular events when compared to anesthetized animals (Figure 1J and 3C-F 4). Device dimensions were altered to allow time-lapse imaging of different stages of C. elegans, first instar Drosophila larvae and zebrafish larvae. Transport of vesicles marked with synaptotagmin tagged with GFP (syt.eGFP) in sensory neurons shows directed motion of synaptic vesicle markers expressed in cholinergic sensory neurons in intact first instar Drosophila larvae. A similar device has been used to carry out time-lapse imaging of heartbeat in ~30 hr post fertilization (hpf) zebrafish larvae. These data show that the simple devices we have developed can be applied to a variety of model systems to study several cell biological and developmental phenomena in vivo.

Simple Microfluidic Devices for &lt;em&gt;in vivo&lt;/em&gt; Imaging of &lt;em&gt;C. elegans&lt;/em&gt;, &lt;em&gt;Drosophila&lt;/em&gt; and Zebrafish

Micro fabricated fluidic devices provide an accessible micro-environment for in vivo studies on small organisms. Simple fabrication processes are available for microfluidic devices using soft lithography techniques. Microfluidic devices have been used for sub-cellular imaging, in vivo laser microsurgery and cellular imaging. In vivo imaging requires immobilization of organisms. This has been achieved using suction, tapered channels, deformable membranes, suction with additional cooling anesthetic gas, temperature sensitive gels, cyanoacrylate glue and anesthetics such as levamisole. Commonly used anesthetics influence synaptic transmission and are known to have detrimental effects on sub-cellular neuronal transport. In this study we demonstrate a membrane based poly-dimethyl-siloxane (PDMS) device that allows anesthetic free immobilization of intact genetic model organisms such as Caenorhabditis elegans (C. elegans), Drosophila larvae and zebrafish larvae. These model organisms are suitable for in vivo studies in microfluidic devices because of their small diameters and optically transparent or translucent bodies. Body diameters range from -10 μm to -800 μm for early larval stages of C. elegans and zebrafish larvae and require microfluidic devices of different sizes to achieve complete immobilization for high resolution time-lapse imaging. These organisms are immobilized using pressure applied by compressed nitrogen gas through a liquid column and imaged using an inverted microscope. Animals released from the trap return to normal locomotion within 10 min. We demonstrate four applications of time-lapse imaging in C. elegans namely, imaging mitochondrial transport in neurons, pre-synaptic vesicle transport in a transport-defective mutant, glutamate receptor transport and Q neuroblast cell division. Data obtained from such movies show that microfluidic immobilization is a useful and accurate means of acquiring in vivo data of cellular and sub-cellular events when compared to anesthetized animals (Figure 1J and 3C-F). Device dimensions were altered to allow time-lapse imaging of different stages of C. elegans, first instar Drosophila larvae and zebrafish larvae. Transport of vesicles marked with synaptotagmin tagged with GFP (syt.eGFP) in sensory neurons shows directed motion of synaptic vesicle markers expressed in cholinergic sensory neurons in intact first instar Drosophila larvae. A similar device has been used to carry out time-lapse imaging of heartbeat in -30 hr post fertilization (hpf) zebrafish larvae. These data show that the simple devices we have developed can be applied to a variety of model systems to study several cell biological and developmental phenomena in vivo.

Infant humor perception from 3- to 6-months and attachment at one year

Infancy is a critical time for the development of secure attachment, which is facilitated by emotionally synchronous interactions with parents. Humor development, which includes shared laughter and joint attention to an event, emerges concurrently with attachment, but little is known regarding the relationship, if any, between humor development and attachment in the first year. Thirty 3-month-old infants were videoed at home each month until they were 6-months old while their parents attempted to amuse them. Frequency of infants’ smiles and laughs served as a measure of “state humor”, and the smiling/laughing subscale of the Infant Behavior Questionnaire-Revised served as a measure of “trait humor”. State and trait humor were not correlated. Lower trait humor as 6 months predicted higher attachment security on the Attachment Q-sort at 12-months (r=.46), suggesting that less good-humored infants elicit greater parental engagement, which works to the benefit of attachment, or vice versa. Future studies should examine the importance of smiling and laughter as they relate to other developmental phenomena in the first year.

Mechanisms of developmental change in infant categorization

Computational models are tools for testing mechanistic theories of learning and development. Formal models allow us to instantiate theories of cognitive development in computer simulations. Model behavior can then be compared to real performance. Connectionist models, loosely based on neural information processing, have been successful in capturing a range of developmental phenomena, in particular on-line within-task category learning by young infants. Here we describe two new models. One demonstrates how age dependent changes in neural receptive field sizes can explain observed changes in on-line category learning between 3 and 10 months of age. The other aims to reconcile two conflicting views of infant categorization by focusing on the different task requirements of preferential looking and manual exploration studies. A dual-memory hypothesis posits that within-task category learning that drives looking time behaviors is based on a fast-learning memory system, whereas categorization based on background experience and assessed by paradigms requiring complex motor behavior relies on a second, slow-learning system. The models demonstrate how emphasizing the mechanistic causes of behaviors leads to discovery of deeper, more explanatory accounts of learning and development.

Preface

Developmental PsychobiologyVolume 54, Issue 6 p. 577-577 Introduction Preface Kevin G. Bath, Corresponding Author Kevin G. Bath kevin_bath@brown.edu Department of Neuroscience, Brown University, Providence, RI 02916Department of Neuroscience, Brown University, Providence, RI 02916Search for more papers by this authorJason D. Zevin, Jason D. Zevin Department of Psychiatry, Weill Cornell Medical College, New York, NY 10021Search for more papers by this author Kevin G. Bath, Corresponding Author Kevin G. Bath kevin_bath@brown.edu Department of Neuroscience, Brown University, Providence, RI 02916Department of Neuroscience, Brown University, Providence, RI 02916Search for more papers by this authorJason D. Zevin, Jason D. Zevin Department of Psychiatry, Weill Cornell Medical College, New York, NY 10021Search for more papers by this author First published: 11 July 2012 https://doi.org/10.1002/dev.21069Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume54, Issue6Special Issue: Developmental Phenomena with Long TailsSeptember 2012Pages 577-577 RelatedInformation

Fungal Ecdysteroid-22-oxidase, a New Tool for Manipulating Ecdysteroid Signaling and Insect Development

Steroid hormones ecdysteroids regulate varieties of developmental processes in insects. Although the ecdysteroid titer can be increased experimentally with ease, its artificial reduction, although desirable, is very difficult to achieve. Here we characterized the ecdysteroid-inactivating enzyme ecdysteroid-22-oxidase (E22O) from the entomopathogenic fungus Nomuraea rileyi and used it to develop methods for reducing ecdysteroid titer and thereby controlling insect development. K(m) and K(cat) values of the purified E22O for oxidizing ecdysone were 4.4 μM and 8.4/s, respectively, indicating that E22O can inactivate ecdysone more efficiently than other ecdysteroid inactivating enzymes characterized so far. The cloned E22O cDNA encoded a FAD-dependent oxidoreductase. Injection of recombinant E22O into the silkworm Bombyx mori interfered with larval molting and metamorphosis. In the hemolymph of E22O-injected pupae, the titer of hormonally active 20-hydroxyecdysone decreased and concomitantly large amounts of inactive 22-dehydroecdysteroids accumulated. E22O injection also prevented molting of various other insects. In the larvae of the crambid moth Haritalodes basipunctalis, E22O injection induced a diapause-like developmental arrest, which, as in normal diapause, was broken by chilling. Transient expression of the E22O gene by in vivo lipofection effectively decreased the 20-hydroxyecdysone titer and blocked molting in B. mori. Transgenic expression of E22O in Drosophila melanogaster caused embryonic morphological defects, phenotypes of which were very similar to those of the ecdysteroid synthesis deficient mutants. Thus, as the first available simple but versatile tool for reducing the internal ecdysteroid titer, E22O could find use in controlling a broad range of ecdysteroid-associated developmental and physiological phenomena.

Response to Discussions by Eldad Iddan and Yavuz Erten

In her response, the author expresses appreciation to Eldad Iddan and Yavuz Erten for their careful and sensitive commentaries on her case presentation. The author finds Iddan's self psychological framework illuminating, particularly the concept of “being with” and the idea that songs are selfobjects. However, she views aggression in the therapeutic process quite differently. The author endorses Erten's contribution on the power of sound to communicate that which has not been put into words and is preverbal. The author also agrees with his belief that the process of mentalization is taking place during the course of her work with Ayda, but she does not agree that songs, as developmental phenomena, should eventually phase out of the therapy. Rather, the author concludes that songs are essential communications and are free associations and, as such, should remain part of the therapy process.

Item-Level Discordance in Parent and Adolescent Reports of Parenting Behavior and Its Implications for Adolescents’ Mental Health and Relationships with Their Parents

The phenomenon of discordance between parents' and children's ratings of the child's mental health symptoms or of parenting behavior until recently has been treated as a problem of reliability. More recent work has sought to identify factors that may influence discordance, yet much remains to be learned about why informants' ratings of developmental phenomena are discordant and the meaning of such discordance. This study examined the extent to which discordance can be treated as a measure of the difference between two equally valid perceptions, and as such an indicator of the quality of the parent-adolescent relationship. One category of concordance and three patterns of discordance were derived from item-level differences in ratings of affection, control, and punitiveness provided by a diverse sample (53% female; 46% Hispanic-American, 35% African-American, 15% European-American, 4% another race/ethnicity) of 484 adolescents aged 12-20 years (M = 15.67, SD = 1.72) and their parents. Over and above adolescents' and parents' independent ratings of parenting, the discordance between these ratings was found to predict adolescent reports of anxiety and conduct disorder symptoms, as well as the quality of the parent-adolescent relationship. This was particularly true when adolescents and parents were discordant in their ratings of affection and when adolescents rated their parents higher on affection than did parents themselves. Implications of these findings and future research directions are discussed.

How to promote holistic development in university students?

How to promote holistic development in university students?

The exemplar methodology: An approach to studying the leading edge of development

The exemplar methodology is a useful, but to date underutilized, approach to studying developmental phenomena. It features a unique sample selection approach whereby individuals, entities, or programs that exemplify the construct of interest in a highly developed manner form the study sample. Studying a sample of highly developed individuals yields an important view of the leading edge of development that cannot be gleaned using other methodologies. A picture of the full range of development requires not only an understanding of typical and deficient growth, as provided by existing methodologies, but also of complete or nearly complete development, as provided by the exemplar methodology. Accordingly, the exemplar methodology represents a critical tool for developmental psychologists. In spite of this, because it has rarely been written about, the exemplar methodology has only been used to study a relatively narrow range of developmental constructs. Therefore, the present article defines the exemplar methodology, addresses key conceptual issues, and briefly outlines steps to utilizing the approach.

Transitions in Craniofacial Biology

The surge of advances in understanding ontological, phylogenetic, pathological, paleoanthropological and genetic insights in development and evolution over the past century has resulted in a profound revolution of our cognizance of biological sciences. The past decade of the human genome project has provided opportunities for diagnosis, prognosis, therapeutic interventions and prevention of dysgenesis, dysmorphology, and disease. The new technologies of imaging and experimental inquiries into developmental phenomena provide insights into evolutionary advances that have taken place to result in the present human structure.

Embryonic Liver Morphology and Morphometry by Magnetic Resonance Microscopic Imaging

Embryonic liver has a unique external morphology and quantitative morphometry, based on magnetic resonance imaging data of human embryos from the Kyoto Collection of Human Embryos. Liver morphogenesis is strongly affected by the adjacent organs and tissues. The left ventricle develops to the left medial-caudal side, which results in the formation of a depression at left medial region and a prominence bilaterally at the cranial surface of the liver between Carnegie Stage (CS)17 and CS19. An imprint of the stomach that formed at the dorsal left-medial region of the liver became more marked with development until CS23. A depression induced by the umbilicus formed at the ventral region of the liver between CS16 and CS19. An indentation caused by the right adrenal gland formed at the dorsal-caudal region of the liver surface from CS20. Morphometric analysis revealed that the volume of the liver increased exponentially from CS14 through CS23. The liver developed preferentially along the dorsoventral axis and right/left axis until CS17, along the craniocaudal axis between CS17 and CS19, and then in all directions after CS19. Several important developmental phenomena, such as differentiation of the diaphragm, the extension of the body axis of the embryo, and the physiologic herniation of the intestine into the umbilical cord, may affect morphometric data. These data contribute to a better understanding of liver development as well as the morphogenesis of adjacent organs, both temporally and spatially, and serve as a useful reference for fetal medicine and prenatal diagnosis.

Focusing the lens: The infant's point of view. Discussion of "Brief interventions with parents, infants, and young children: A Framework for thinking".

This is a discussion of the article "Brief Interventions With Parents, Infants, and Young Children: A Framework for Thinking by Louise Emmanuel." Questions of symptom formation, the difference between a defense and developmental phenomena, and different therapeutic techniques are explored from the perspective of The Baby as Subject (an infant-parent psychotherapy approach developed at the Royal Children's Hospital in Melbourne, Australia). The relationship between feeding difficulties and the dynamics of the infant-parent attachment relationship are discussed with reference to whether the infant's apparent self-sufficiency is interpersonally generated and whether bids for autonomy are a sign of healthy, age-appropriate developmental drives at play. The use of representational toys in infant-parent psychotherapy to enable infants and toddlers to represent their experience or for the therapist to visually express what he or she understands the infant's experience to be and thus to work directly with the infant's representations is outlined. In addition to the linguistic content of verbal interpretations, the infant is receptive to the experience of another thinking mind and the emotional language, facial expressions, and gestures that also convey to the baby the experience of being understood or misunderstood.

The α Subunit of the G Protein G13 Regulates Activity of One or More Gli Transcription Factors Independently of Smoothened

Smoothened (Smo) is a seven-transmembrane (7-TM) receptor that is essential to most actions of the Hedgehog family of morphogens. We found previously that Smo couples to members of the G(i) family of heterotrimeric G proteins, which in some cases are integral although alone insufficient in the activation of Gli transcription factors through Hedgehog signaling. In response to a report that the G(12/13) family is relevant to Hedgehog signaling as well, we re-evaluated the coupling of Smo to one member of this family, G(13), and investigated the capacity of this and other G proteins to activate one or more of forms of Gli. We found no evidence that Smo couples directly to G(13). We found nonetheless that Gα(13) and to some extent Gα(q) and Gα(12) are able to effect activation of Gli(s). This capacity is realized in some cells, e.g. C3H10T1/2, MC3T3, and pancreatic cancer cells, but not all cells. The mechanism employed is distinct from that achieved through canonical Hedgehog signaling, as the activation does not involve autocrine signaling or in any other way require active Smo and does not necessarily involve enhanced transcription of Gli1. The activation by Gα(13) can be replicated through a G(q)/G(12/13)-coupled receptor, CCK(A), and is attenuated by inhibitors of p38 mitogen-activated protein kinase and Tec tyrosine kinases. We posit that G proteins, and perhaps G(13) in particular, provide access to Gli that is independent of Smo and that they thus establish a basis for control of at least some forms of Gli-mediated transcription apart from Hedgehogs.

On culture and human development: Interview with Barbara Rogoff

In this interview Professor Barbara Rogoff explores the many ways in which culture shapes the course of human development, and illustrates this with several findings from her past as well as most recent work. These reveal the vital importance of growing up in a family and a community for the human child and participating, from early on, in their various rituals and practices. Building on and enriching cultural psychological sources, Professor Rogoff offers us a comprehensive framework with which to understand both cultural and developmental phenomena and, above all, their multiple intersections. Her suggestions will prove to be invaluable for all the students of culture and community life in their ontogenetic expression.

Secrets of palm oil biosynthesis revealed

Globally, vegetable oils are harvested from a handful of oil crops at an annual rate exceeding 100 million tons (1). Most oils are used for human or animal consumption, although a minor fraction is derivatized to oleochemicals. More recently, an increasing amount of vegetable oil is being diverted to the production of biodiesel [i.e., fatty acid (FA) methylesters], and is an attractive feedstock for the so-called “drop-in” biofuels of the future, further increasing the demand on this commodity (2). Because of the commercial importance of vegetable oils, during the past 30 y, the biosynthesis of FAs and their derived acyl lipids, especially plant triacylglycerols (TAGs), has attracted a tremendous amount of scientific interest, resulting in the identification and characterization of the functions of most of the enzymes involved in their production and sequestration (3). In addition, researchers have attempted to understand the quantitative regulation of biosynthesis with the ultimate goal of increasing oil production in crops. Practically all investigations in this field have been conducted in developing embryos of oilseeds, most notably in Arabidopsis. As cDNA sequences of enzymes considered “rate-limiting” became available in the mid-1990s, increasing oil production in plants has become the “holy grail” of plant FA biochemistry (4, 5). However, even though there are more than a dozen reports of marginal increases of seed oil through genetic manipulation, channeling carbon intermediates to TAGs has had very limited success, and no high-oil engineered crop is on the market (6, 7). Only very recently a comprehensive analysis of oil palm mesoderm during fruit ripening was published by Tranbarger et al. (8). With this investigation, Tranberger et al. stepped “outside the box” (i.e., the seed) and delivered a first detailed insight into the compositional, hormonal, and transcriptional changes during the different phases of oil palm fruit development and compared their finding to the established knowledge of oilseed development. While comparing the transcriptomes and metabolomes of developing oil accumulating mesoderm of oil palm (Elaeis guineensis) and sugar accumulating mesoderm of date palm (Phoenix dactylifera), Bourgis et al. (9) follow a strategy that enables them to differentiate metabolic determinants of the respective tissues from other developmental phenomena.

PERFORMANCE DIMENSION OF ULUL ALBAB LEADERSHIP MODEL

This Study specifically analyses the structure of the leadership performance which developed by the Rector of the State Islamic University (UIN) of Malang from 1998 to 2008 in order to develop the higher Islamic university he led. This is basing on the developmental phenomena of UIN Malang which is institutionally changing, the disciplines paradigm of combining science and Islam, and the highly improving physical structure development.This research applies positivistic qualitative approach focusing on the leadership reality in UIN Malang which proceeds dynamically as being proposed by Giddens (1974). Conceptually, this research is a field research using the technique of on going analysis approach combined with content analysis approach proposed by Krippendorff through Blumer’s symbolic interaction approach. This research focused on finding the answer of leadership basic concept, a leader’s performance dimensions, and a leadership style that developed by the Rector of UIN Malang from 1998 to 2008.The research reveals that the structure of leadership basic concept developed by the Rector of UIN Malang from 1998 to 2008, which the researcher names as as the Performance Dimension of Ulul Albab Leadership Model possesses the character strength in the form of; (1) spiritual deepness, (2) ethical conduct, (3) science broadness and (4) professional maturity.

What Is Epigenetics?

The cells in a multicellular organism have nominally identical DNA sequences (and therefore the same genetic instruction sets), yet maintain different terminal phenotypes. This nongenetic cellular memory, which records developmental and environmental cues (and alternative cell states in unicellular organisms), is the basis of epi-(above)–genetics. Movie 1 Science senior editor Guy Riddihough taps experts for their definition of epigenetics. The lack of identified genetic determinants that fully explain the heritability of complex traits, and the inability to pinpoint causative genetic effects in some complex diseases, suggest possible epigenetic explanations for this missing information. This growing interest, along with the desire to understand the “deprogramming” of differentiated cells into pluripotent/totipotent states, has led to “epigenetic” becoming shorthand for many regulatory systems involving DNA methylation, histone modification, nucleosome location, or noncoding RNA. This is to be encouraged, but the labeling of nongenetic systems as epigenetic by default has the potential to confuse (see the related video). So what is epigenetics? An epigenetic system should be heritable, self-perpetuating, and reversible (Bonasio et al. , p. [612][1]). Whether histone modifications (and many noncoding RNAs) are epigenetic is debated; it is likely that relatively few of these modifications or RNAs will be self-perpetuating and inherited. Looking beyond DNA-associated molecules, prions (infectious proteins) are clearly epigenetic, perpetuating themselves through altered folding states. These states can act as sensors of environmental stress and, through the phenotypic changes they promote, potentially drive evolution (Halfmann and Lindquist, p. [629][2]). ![Figure][3] CREDIT: C. BICKEL/ SCIENCE Some metazoans undergo genome-wide reprogramming of DNA methylation and histone modifications during gametogenesis and embryogenesis (Feng et al. , p. [622][4]), which may suppress the activity of potentially deleterious DNA sequences. Furthermore, the activity of various populations of small noncoding RNAs (Bourc' his and Voinnet, p. [617][5]) probably act as tags for these deleterious sequences. These small RNAs may also be involved in assessing parental compatibility at fertilization. Similar RNAs are likely to be important determinants in paramutation, where homologous DNA sequences communicate in trans to establish heritable expression states (Chandler, p. [628][6]). Reprogramming is also critical for developmental phenomena such as imprinting in both plants and mammals, as well as for cell differentiation, and is linked to the establishment of pluripotency in gametes and zygotes. A News Focus story by Kaiser (p. [576][7]) examines efforts to treat cancer patients with drugs that reverse the abnormal epigenetic patterns found in tumors, and a paper in Science Translational Medicine [*][8] describes the use of epigenetic markers to predict which liver cancer patients will respond to an anticancer drug that blocks DNA methylation. Papers in Science Signaling discuss signaling pathways that alter epigenetic patterning, posttranscriptional regulation of signaling molecules by microRNAs, and transcriptional networks. Articles on Science Careers trace careers embracing a translational approach to epigenetics. [1]: /lookup/doi/10.1126/science.1191078 [2]: /lookup/volpage/330/629?iss=6004 [3]: pending:yes [4]: /lookup/doi/10.1126/science.1190614 [5]: /lookup/doi/10.1126/science.1194776 [6]: /lookup/doi/10.1126/science.1191044 [7]: /lookup/volpage/330/576?iss=6004 [8]: #fn-1

Contemporary Psychoanalytic Perspectives on Attachment

Bowlby's theoretical conception of attachment represented a highly original and substantively unique paradigm for understanding the psychological and social development of human infants, as well as the short- and longer-term sequelae of failures in attachment. His ideas have also been highly generative, leading to a vast scientific literature that now encompasses several different disciplinary domains. Moreover, unlike many psychoanalytic developmental concepts, Bowlby's attachment theory is regarded by many social scientists as eminently researchable. Nevertheless, despite increasing popularity, Bowlby's ideas about human development are not universally embraced by dynamically oriented clinicians, who may favor other theoretical frameworks to explain developmental phenomena or psychopathology, or perhaps both. How are we to understand Bowlby's ideas about attachment, separation, and loss in light of other psychoanalytic developmental theories? To address this issue, the “goodness of fit” between attachment theory and four important contemporary psychoanalytic frameworks for understanding human development will be examined. Selected because each offers a unique vision of development, the four are Harry Stack Sullivan's interpersonal model, Margaret Mahler's separation-individuation theory, Erik Erikson's epigenetic model, and Heinz Kohut's psychology of the self. Each will be examined in detail, with particular attention to controversies and points of convergence.