Evolutionarily conserved TRH neuropeptide pathway regulates growth in .

In vertebrates thyrotropin-releasing hormone (TRH) is a highly conserved neuropeptide that exerts the hormonal control of thyroid-stimulating hormone (TSH) levels as well as neuromodulatory functions. However, a functional equivalent in protostomian animals remains unknown, although TRH receptors are conserved in proto- and deuterostomians. Here we identify a TRH-like neuropeptide precursor in that belongs to a bilaterian family of TRH precursors.

Neuropeptides as Regulators of Behavior in Insects.

Neuropeptides are by far the largest and most diverse group of signaling molecules in multicellular organisms. They are ancient molecules important in regulating a multitude of processes. Their small proteinaceous character allowed them to evolve and radiate quickly into numerous different molecules.

Characterization of a neuropeptide F receptor in the tsetse fly, Glossina morsitans morsitans.

Neuropeptides related to mammalian neuropeptide Y (NPY) and insect neuropeptide F (NPF) are conserved throughout Metazoa and intimately involved in a wide range of biological processes. In insects NPF is involved in regulating feeding, learning, stress and reproductive behavior. Here we identified and characterized an NPF receptor of the tsetse fly, Glossina morsitans morsitans, the sole transmitter of Trypanosoma parasites causing sleeping sickness.

Molecular characterization of a short neuropeptide F signaling system in the tsetse fly, Glossina morsitans morsitans.

Neuropeptides of the short neuropeptide F (sNPF) family are widespread among arthropods and found in every sequenced insect genome so far. Functional studies have mainly focused on the regulatory role of sNPF in feeding behavior, although this neuropeptide family has pleiotropic effects including in the control of locomotion, osmotic homeostasis, sleep, learning and memory. Here, we set out to characterize and determine possible roles of sNPF signaling in the haematophagous tsetse fly Glossina morsitans morsitans, a vector of African Trypanosoma parasites causing human and animal African trypanosomiasis.

Peptidomics of Neuropeptidergic Tissues of the Tsetse Fly Glossina morsitans morsitans.

Neuropeptides and peptide hormones are essential signaling molecules that regulate nearly all physiological processes. The recent release of the tsetse fly genome allowed the construction of a detailed in silico neuropeptide database (International Glossina Genome Consortium, Science 344, 380-386 (2014)), as well as an in-depth mass spectrometric analysis of the most important neuropeptidergic tissues of this medically and economically important insect species. Mass spectrometric confirmation of predicted peptides is a vital step in the functional characterization of neuropeptides, as in vivo peptides can be modified, cleaved, or even mispredicted.

Epigenetics and locust life phase transitions.

Insects are one of the most successful classes on Earth, reflected in an enormous species richness and diversity. Arguably, this success is partly due to the high degree to which polyphenism, where one genotype gives rise to more than one phenotype, is exploited by many of its species. In social insects, for instance, larval diet influences the development into distinct castes; and locust polyphenism has tricked researchers for years into believing that the drastically different solitarious and gregarious phases might be different species.

Silencing D. melanogaster lgr1 impairs transition from larval to pupal stage.

G protein-coupled receptors (GPCRs) play key roles in a wide diversity of physiological processes and signalling pathways. The leucine-rich repeats containing GPCRs (LGRs) are a subfamily that is well-conserved throughout most metazoan phyla and have important regulatory roles in vertebrates. Here, we report on the critical role of Drosophila melanogaster LGR1, the fruit fly homologue of the vertebrate glycoprotein hormone receptors, in development as a factor involved in the regulation of pupariation.

Cloning, constitutive activity and expression profiling of two receptors related to relaxin receptors in Drosophila melanogaster.

Leucine-rich repeat containing G protein-coupled receptors (LGRs) comprise a cluster of transmembrane proteins, characterized by the presence of a large N-terminal extracellular domain. This receptor group can be classified into three subtypes. Belonging to the subtype C LGRs are the mammalian relaxin receptors LGR7 (RXFP1) and LGR8 (RXFP2), which mediate important reproductive and other processes.

The ovicidal, larvacidal and adulticidal properties of 5,5'-dimethyl-2,2'-bipyridyl against Drosophila melanogaster.

Insecticide resistance has limited the number of available chemical options for insect pest control. Hence there is a need for new chemistries with novel modes of action. Here we investigate the mode of action for an insecticide that has not yet been released for commercial use.

An evolutionary comparison of leucine-rich repeat containing G protein-coupled receptors reveals a novel LGR subtype.

Leucine-rich repeat containing G protein-coupled receptors or LGRs are receptors with important functions in development and reproduction. Belonging to this evolutionarily conserved group of receptors are the well-studied glycoprotein hormone receptors and relaxin receptors in mammals, as well as the bursicon receptor, which triggers cuticle hardening and tanning in freshly enclosed insects. In this study, the numerous LGR sequences in different animal phyla are analyzed and compared.

Neuropeptide receptors as possible targets for development of insect pest control agents.

Vaious insect species have a severe impact on human welfare and environment and thus force us to continuously develop novel agents for pest control. Neuropeptides constitute a very versatile class of bioactive messenger molecules that initiate and/or regulate a wide array of vital biological processes in insects by acting on their respective receptors in the plasmamembrane of target cells. These receptors belong to two distinct categories of signal transducing proteins, i.

Tachykinin-related peptides and their receptors in invertebrates: a current view.

Members of the tachykinin peptide family have been well conserved during evolution and are mainly expressed in the central nervous system and in the intestine of both vertebrates and invertebrates. In these animals, they act as multifunctional messengers that exert their biological effects by specifically interacting with a subfamily of structurally related G protein-coupled receptors. Despite the identification of multiple tachykinin-related peptides (TKRPs) in species belonging to the insects, crustaceans, mollusks and echiuroid worms, only five invertebrate receptors harboring profound sequence similarities to mammalian receptors for tachykinins have been functionally characterized to date.

Identification and validation of housekeeping genes in brains of the desert locust Schistocerca gregaria under different developmental conditions.

Background: To obtain reliable quantitative RT-PCR data, normalization relative to stable housekeeping genes is required. However, in practice, expression levels of 'typical' housekeeping genes have been found to vary between tissues and under different experimental conditions. To date, validation studies of reference genes in insects are extremely rare and have never been performed in locusts.

Comparative genomics of leucine-rich repeats containing G protein-coupled receptors and their ligands.

Leucine-rich repeats containing G protein-coupled receptors (LGRs) constitute a unique cluster of transmembrane proteins sharing a large leucine-rich extracellular domain for hormone binding. In mammals, LGRs steer important developmental, metabolic and reproductive processes as receptors for glycoprotein hormones and insulin/relaxin-related proteins. In insects, a receptor structurally related to human LGRs mediates the activity of the neurohormone bursicon thereby regulating wing expansion behaviour and remodelling of the newly synthesized exoskeleton.

Evolutionary conservation of bursicon in the animal kingdom.

Bursicon bioactivity is essential for tanning of the exoskeleton and for wing spreading behavior that occur in newly emerged adult insects. Previously, we demonstrated that in the fruit fly, Drosophila melanogaster, bursicon exists as a heterodimeric cystine knot protein that activates the leucine-rich repeats containing G protein-coupled receptor 2 (DLGR2). By performing similarity based in silico searches in genomic and complementary DNA databases, we identified bursicon homologous sequences in several protostomian as well as deuterostomian invertebrates.

Insect neuropeptide and peptide hormone receptors: current knowledge and future directions.

Peptides form a very versatile class of extracellular messenger molecules that function as chemical communication signals between the cells of an organism. Molecular diversity is created at different levels of the peptide synthesis scheme. Peptide messengers exert their biological functions via specific signal-transducing membrane receptors.