The embryonic role of juvenile hormone in the firebrat, reveals its function before its involvement in metamorphosis.

To gain insights into how juvenile hormone (JH) came to regulate insect metamorphosis, we studied its function in the ametabolous firebrat, . Highest levels of JH occur during late embryogenesis, with only low levels thereafter. Loss-of-function and gain-of-function experiments show that JH acts on embryonic tissues to suppress morphogenesis and cell determination and to promote their terminal differentiation.

Resonant x-ray diffraction measurements in charge ordered kagome superconductors KVSband RbVSb.

We report on (resonant) x-ray diffraction experiments on the normal state properties of kagome-lattice superconductors KVSband RbVSb. We have confirmed previous reports indicating that the charge density wave (CDW) phase is characterized by a doubling of the unit cell in all three crystallographic directions. By monitoring the temperature dependence of Bragg peaks associated with the CDW phase, we ascertained that it develops gradually over several degrees, as opposed to CsVSb, where the CDW peak intensity saturates promptly just below the CDW transition temperature.

The embryonic role of juvenile hormone in the firebrat, , reveals its function before its involvement in metamorphosis.

To gain insights into how juvenile hormone (JH) came to regulate insect metamorphosis, we studied its function in the ametabolous firebrat, . Highest levels of JH occur during late embryogenesis, with only low levels thereafter. Loss-of-function and gain-of-function experiments show that JH acts on embryonic tissues to suppress morphogenesis and cell determination and to promote their terminal differentiation.

Ultra-thin lithium aluminate spinel ferrite films with perpendicular magnetic anisotropy and low damping.

Ultra-thin films of low damping ferromagnetic insulators with perpendicular magnetic anisotropy have been identified as critical to advancing spin-based electronics by significantly reducing the threshold for current-induced magnetization switching while enabling new types of hybrid structures or devices. Here, we have developed a new class of ultra-thin spinel structure LiAlFeO (LAFO) films on MgGaO (MGO) substrates with: 1) perpendicular magnetic anisotropy; 2) low magnetic damping and 3) the absence of degraded or magnetic dead layers. These films have been integrated with epitaxial Pt spin source layers to demonstrate record low magnetization switching currents and high spin-orbit torque efficiencies.

Drosophila postembryonic nervous system development: a model for the endocrine control of development.

During postembryonic life, hormones, including ecdysteroids, juvenile hormones, insulin-like peptides, and activin/TGFβ ligands act to transform the larval nervous system into an adult version, which is a fine-grained mosaic of recycled larval neurons and adult-specific neurons. Hormones provide both instructional signals that make cells competent to undergo developmental change and timing cues to evoke these changes across the nervous system. While touching on all the above hormones, our emphasis is on the ecdysteroids, ecdysone and 20-hydroxyecdysone (20E).

Understanding Signatures of Emergent Magnetism in Topological Insulator/Ferrite Bilayers.

Magnetic insulator-topological insulator heterostructures have been studied in search of chiral edge states via proximity induced magnetism in the topological insulator, but these states have been elusive. We identified MgAl_{0.5}Fe_{1.

is the larval member of the molecular trinity that directs metamorphosis.

The molecular control of insect metamorphosis from larva to pupa to adult has long been a mystery. The Broad and E93 transcription factors, which can modify chromatin domains, are known to direct the production of the pupa and the adult, respectively. We now show that chinmo, a gene related to broad, is essential for the repression of these metamorphic genes.

Anisotropic Magnon Spin Transport in Ultrathin Spinel Ferrite Thin Films─Evidence for Anisotropy in Exchange Stiffness.

Magnon-mediated spin flow in magnetically ordered insulators enables long-distance spin-based information transport with low dissipation. In the materials studied to date, no anisotropy has been observed in the magnon propagation length as a function of propagation direction. Here, we report measurements of magnon spin transport in a spinel ferrite, magnesium aluminum ferrite MgAlFeO (MAFO), which has a substantial in-plane 4-fold magnetic anisotropy.

, Golden Oil, and : A History of Juvenile Hormone Research.

Juvenile hormone (JH) is a unique sesquiterpenoid hormone which regulates both insect metamorphosis and insect reproduction. It also may be utilized by some insects to mediate polyphenisms and other life history events that are environmentally regulated. This article details the history of the research on this versatile hormone that began with studies by V.

A Life's Journey Through Insect Metamorphosis.

This autobiographical article describes the research career of Lynn M. Riddiford from its early beginnings in a summer program for high school students at Jackson Laboratory to the present "retirement" at the Friday Harbor Laboratories. The emphasis is on her forays into many areas of insect endocrinology, supported by her graduate students and postdoctoral associates.

The evolution of insect metamorphosis: a developmental and endocrine view.

Developmental, genetic and endocrine data from diverse taxa provide insight into the evolution of insect metamorphosis. We equate the larva-pupa-adult of the Holometabola to the pronymph-nymph-adult of hemimetabolous insects. The hemimetabolous pronymph is a cryptic embryonic stage with unique endocrinology and behavioural modifications that probably served as preadaptations for the larva.

Juvenile hormone reveals mosaic developmental programs in the metamorphosing optic lobe of .

The development of the adult optic lobe (OL) of is directed by a wave of ingrowth of the photoreceptors over a 2-day period at the outset of metamorphosis, which is accompanied by the appearance of the pupal-specific transcription factor Broad-Z3 (Br-Z3) and expression of early drivers in OL neurons. During this time, there are pulses of ecdysteroids that time the metamorphic events. At the outset, the transient appearance of juvenile hormone (JH) prevents precocious development of the OL caused by the ecdysteroid peak that initiates pupariation, but the artificial maintenance of JH after this time misdirects subsequent development.

Genetic tools to study juvenile hormone action in Drosophila.

The insect juvenile hormone receptor is a basic helix-loop-helix (bHLH), Per-Arnt-Sim (PAS) domain protein, a novel type of hormone receptor. In higher flies like Drosophila, the ancestral receptor germ cell-expressed (gce) gene has duplicated to yield the paralog Methoprene-tolerant (Met). These paralogous receptors share redundant function during development but play unique roles in adults.

The role of juvenile hormone in dominance behavior, reproduction and cuticular pheromone signaling in the caste-flexible epiponine wasp, Synoeca surinama.

Background: The popular view on insect sociality is that of a harmonious division of labor among two morphologically distinct and functionally non-overlapping castes. But this is a highly derived state and not a prerequisite for a functional society. Rather, caste-flexibility is a central feature in many eusocial wasps, where adult females have the potential to become queens or workers, depending on the social environment.

The developmental control of size in insects.

The mechanisms that control the sizes of a body and its many parts remain among the great puzzles in developmental biology. Why do animals grow to a species-specific body size, and how is the relative growth of their body parts controlled to so they grow to the right size, and in the correct proportion with body size, giving an animal its species-characteristic shape? Control of size must involve mechanisms that somehow assess some aspect of size and are upstream of mechanisms that regulate growth. These mechanisms are now beginning to be understood in the insects, in particular in Manduca sexta and Drosophila melanogaster.

Juvenile hormone regulates body size and perturbs insulin signaling in Drosophila.

The role of juvenile hormone (JH) in regulating the timing and nature of insect molts is well-established. Increasing evidence suggests that JH is also involved in regulating final insect size. Here we elucidate the developmental mechanism through which JH regulates body size in developing Drosophila larvae by genetically ablating the JH-producing organ, the corpora allata (CA).

Reproductive status, endocrine physiology and chemical signaling in the Neotropical, swarm-founding eusocial wasp Polybia micans.

In the evolution of caste-based societies in Hymenoptera, the classical insect hormones juvenile hormone (JH) and ecdysteroids were co-opted into new functions. Social wasps, which show all levels of sociality and lifestyles, are an ideal group in which to study such functional changes. Virtually all studies on the physiological mechanisms underlying reproductive division of labor and caste functions in wasps have been done on independent-founding paper wasps, and the majority of these studies have focused on species specially adapted for overwintering.

Regulation of onset of female mating and sex pheromone production by juvenile hormone in Drosophila melanogaster.

Juvenile hormone (JH) coordinates timing of female reproductive maturation in most insects. In Drosophila melanogaster, JH plays roles in both mating and egg maturation. However, very little is known about the molecular pathways associated with mating.

Nancy E. Beckage (1950-2012): pioneer in insect host-parasite interactions.

Nancy E. Beckage is widely recognized for her pioneering work in the field of insect host-parasitoid interactions beginning with endocrine influences of the tobacco hornworm, Manduca sexta, host and its parasitoid wasp Apanteles congregatus (now Cotesia congregata) on each other's development. Moreover, her studies show that the polydnavirus carried by the parasitoid wasp not only protects the parasitoid from the host's immune defenses, but also is responsible for some of the developmental effects of parasitism.

A molt timer is involved in the metamorphic molt in Manduca sexta larvae.

Manduca sexta larvae are a model for growth control in insects, particularly for the demonstration of critical weight, a threshold weight that the larva must surpass before it can enter metamorphosis on a normal schedule, and the inhibitory action of juvenile hormone on this checkpoint. We examined the effects of nutrition on allatectomized (CAX) larvae that lack juvenile hormone to impose the critical weight checkpoint. Normal larvae respond to prolonged starvation at the start of the last larval stage, by extending their subsequent feeding period to ensure that they begin metamorphosis above critical weight.

The juvenile hormone signaling pathway in insect development.

The molecular action of juvenile hormone (JH), a regulator of vital importance to insects, was until recently regarded as a mystery. The past few years have seen an explosion of studies of JH signaling, sparked by a finding that a JH-resistance gene, Methoprene-tolerant (Met), plays a critical role in insect metamorphosis. Here, we summarize the recently acquired knowledge on the capacity of Met to bind JH, which has been mapped to a particular ligand-binding domain, thus establishing this bHLH-PAS protein as a novel type of an intracellular hormone receptor.