Insecticides Based on Differences in Metabolic Pathways

Insects have been major pests of humankind at least since the beginning of recorded history. To this day insects continue to cause problems in domestic, agricultural, and health situations. It is no wonder that people have continually sought new solutions to controlling insect pests. Even when new control methods are discovered and established, insects evolve into resistant species so that the method is only of real value for a few brief years. Modern science and technology are now enabling scientists to tear away the fabric that has so long masked physiological and biochemical events critical to insects. Armed with this new knowledge, researchers should be able to develop novel control strategies that focus on key physiological, biological, and biochemical events such that they can be altered, influenced, disrupted, and/or inhibited. Three promising areas that may lead or are currently leading to new insect control methods are the cuticle, prostaglandins, and steroids. We discuss each of these areas in regard to their biological significance, current research, metabolic inhibitors and their modes of action

Transition to adulthood for homeless adolescents

Education plays a critical role in how adolescents mature into adults. A vulnerable, and often forgotten, sub-population of the poor is homeless youth, for whom lack of a stable or adequate residence creates a unique set of educational barriers. The Center for Higher Education Policy Analysis (CHEPA) spent 18 months documenting the experiences of homeless adolescents in Los Angeles, deriving data from 123 interviews with homeless adolescents between the ages of 14 and 19, and an additional 45 interviews with shelter staff, social workers, parents, teachers, and school district administrators. Follow-up interviews were conducted with 30 of the youth to understand their experiences in greater depth. Over 400 hours were dedicated to observing the daily lives of homeless youth. The project had two primary goals: (1) To give a voice to homeless youth who are frequently powerless and invisible; and (2) To initiate a dialog with policymakers and practitioners concerning the improvement of educational policy as it pertains to homeless youth. The following research questions framed the analysis: (1) What are the lives of homeless adolescents like? (2) How do homeless youth conceptualize themselves? (3) How do they spend their time? (4) How do they negotiate educational and social barriers? (5) How do they create support systems in and out of school? and (6) What are the different factors they prioritize as crucial to their development? The authors conclude that the current educational system is either irrelevant or hostile to the daily needs of homeless youth. Based on study findings, the authors suggest that policy conversation needs to turn towards addressing specific educational needs to prevent youth from being trapped in a cycle of homelessness. The creation of alternative educational opportunities, mentoring programs, and closer working relationships between shelters and schools warrants greater public discussion on federal, state, and local levels. (Contains 5 boxes and 1 table.) [This research was supported by the John Randolph Haynes and Dora Haynes Foundation.]https://scholarlycommons.pacific.edu/ed-facbooks/1005/thumbnail.jp

Multi-monoubiquitylation controls VASP-mediated actin dynamics Icon for The Forest of Biologists

The actin cytoskeleton performs multiple cellular functions, and as such, actin polymerization must be tightly regulated. We previously demonstrated that reversible, non-degradative ubiquitylation regulates the function of the actin polymerase VASP in developing neurons. However, the underlying mechanism of how ubiquitylation impacts VASP activity was unknown. Here, we show that mimicking multi-monoubiquitylation of VASP at K240 and K286 negatively regulates VASP interactions with actin. Using in vitro biochemical assays, we demonstrate the reduced ability of multi-monoubiquitylated VASP to bind, bundle, and elongate actin filaments. However, multi-monoubiquitylated VASP maintained the ability to bind and protect barbed ends from capping protein. Finally, we demonstrate the electroporation of recombinant multi-monoubiquitylated VASP protein altered cell spreading morphology. Collectively, these results suggest a mechanism in which ubiquitylation controls VASP-mediated actin dynamics

A novel Netrin-1-sensitive mechanism promotes local SNARE-mediated exocytosis during axon branching

Developmental axon branching dramatically increases synaptic capacity and neuronal surface area. Netrin-1 promotes branching and synaptogenesis, but the mechanism by which Netrin-1 stimulates plasma membrane expansion is unknown. We demonstrate that SNARE-mediated exocytosis is a prerequisite for axon branching and identify the E3 ubiquitin ligase TRIM9 as a critical catalytic link between Netrin-1 and exocytic SNARE machinery in murine cortical neurons. TRIM9 ligase activity promotes SNARE-mediated vesicle fusion and axon branching in a Netrin-dependent manner. We identified a direct interaction between TRIM9 and the Netrin-1 receptor DCC as well as a Netrin-1–sensitive interaction between TRIM9 and the SNARE component SNAP25. The interaction with SNAP25 negatively regulates SNARE-mediated exocytosis and axon branching in the absence of Netrin-1. Deletion of TRIM9 elevated exocytosis in vitro and increased axon branching in vitro and in vivo. Our data provide a novel model for the spatial regulation of axon branching by Netrin-1, in which localized plasma membrane expansion occurs via TRIM9-dependent regulation of SNARE-mediated vesicle fusion.American Heart Association (Fellowship 0615692T)National Institutes of Health (U.S.) (Grant GM68678

Mouse Acetylcholinesterase Enhances Neurite Outgrowth of Rat R28 Cells Through Interaction With Laminin-1

The enzyme acetylcholinesterase (AChE) terminates synaptic transmission at cholinergic synapses by hydrolyzing the neurotransmitter acetylcholine, but can also exert ‘non-classical’, morpho-regulatory effects on developing neurons such as stimulation of neurite outgrowth. Here, we investigated the role of AChE binding to laminin-1 on the regulation of neurite outgrowth by using cell culture, immunocytochemistry, and molecular biological approaches. To explore the role of AChE, we examined fiber growth of cells overexpressing different forms of AChE, and/or during their growth on laminin-1. A significant increase of neuritic growth as compared with controls was observed for neurons over-expressing AChE. Accordingly, addition of globular AChE to the medium increased total length of neurites. Co-transfection with PRIMA, a membrane anchor of AChE, led to an increase in fiber length similar to AChE overexpressing cells. Transfection with an AChE mutant that leads to the retention of AChE within cells had no stimulatory effect on neurite length. Noticeably, the longest neurites were produced by neurons overexpressing AChE and growing on laminin-1, suggesting that the AChE/laminin interaction is involved in regulating neurite outgrowth. Our findings demonstrate that binding of AChE to laminin-1 alters AChE activity and leads to increased neurite growth in culture. A possible mechanism of the AChE effect on neurite outgrowth is proposed due to the interaction of AChE with laminin-1

Clathrin mediates integrin endocytosis for focal adhesion disassembly in migrating cells

A new mechanism for focal adhesion disassembly is described involving microtubule-stimulated endocytosis of integrins at focal adhesions

Persistent and polarised global actin flow is essential for directionality during cell migration

Cell migration is hypothesized to involve a cycle of behaviours beginning with leading edge extension. However, recent evidence suggests that the leading edge may be dispensable for migration, raising the question of what actually controls cell directionality. Here, we exploit the embryonic migration of Drosophila macrophages to bridge the different temporal scales of the behaviours controlling motility. This approach reveals that edge fluctuations during random motility are not persistent and are weakly correlated with motion. In contrast, flow of the actin network behind the leading edge is highly persistent. Quantification of actin flow structure during migration reveals a stable organization and asymmetry in the cell-wide flowfield that strongly correlates with cell directionality. This organization is regulated by a gradient of actin network compression and destruction, which is controlled by myosin contraction and cofilin-mediated disassembly. It is this stable actin-flow polarity, which integrates rapid fluctuations of the leading edge, that controls inherent cellular persistence

Extraordinary exposed in early motherhood - a qualitative study exploring experiences of mothers with type 1 diabetes

<p>Abstract</p> <p>Background</p> <p>Women with type 1 diabetes face several challenges during pregnancy, childbirth and in relation to breastfeeding. It is therefore of utmost importance to consider their need for specific support, early postpartum as well as in daily life after discharge from maternity care. Few studies have investigated these aspects of healthcare. The aim of this study was to explore experiences after childbirth regarding breastfeeding, glycemic control, support and well-being in women with type 1 diabetes.</p> <p>Methods</p> <p>A hermeneutic reflective life world research approach was used in this qualitative study. Data was gathered through audio-recorded focus group discussions and individual interviews with 23 women with type 1 diabetes, 6-24 months after childbirth. After verbatim transcription, the text was analyzed in order to identify themes of meaning and a conclusive interpretation of the explored phenomenon.</p> <p>Results</p> <p>Experiences of extraordinary exposure challenged the women with type 1 diabetes in their transition to early motherhood. The exposure included a struggle with breastfeeding, although with a driving force to succeed. Everyday life was filled with uncertainty and unpredictability related to one's own unstable glycemic control and the women down-prioritized their own needs in favor of the child. A feeling of being disconnected from professional care further contributed to the experiences of extraordinary exposure.</p> <p>Conclusion</p> <p>In early motherhood women with type 1 diabetes have a great need for support in managing daily life postpartum, which requires contemporary approaches to overlap insufficient linkage between health care professionals in maternity and child health care, and diabetes care.</p