Identification of ecdysteroids and ecdysteroidogenic genes in dragonflies and damselflies.

Ecdysteroids are critical in regulating biological processes such as ecdysis, metamorphosis, embryogenesis, and reproduction in insects. Nevertheless, the ecdysteroid repertoire and expression patterns of their synthesis genes in Odonata (dragonflies and damselflies), which belong to the most-ancestral winged insect group, have remained elusive. In this study, we examined the ecdysteroid profile of eight Odonata species and the ecdysteroid fluctuation during metamorphosis in the damselfly Ischnura senegalensis (Zygoptera, Coenagionidae) and the dragonfly Pseudothemis zonata (Anisoptera, Libellulidae).

Functionality of highly diverged Imd like genes identified in stinkbugs and bedbugs.

The IMD pathway is an innate immune signalling pathway regulating antibacterial humoral defence responses, and is highly conserved among diverse insects and other organisms. However, genomic studies among hemipterans suggested that certain insects from this order may lack the Imd gene, a key component of the IMD immune pathway. Our previous work identified Imd in the brown-winged green stinkbug Plautia stali, which showed low sequence homology to other insect Imd genes but exhibited functionality in the IMD pathway.

Peculiar structural features of midgut symbiotic organ in the early development of the stinkbug Plautia stali Scott, 1874 (Hemiptera: Pentatomidae).

Many insects have symbiotic microorganisms within their body. Such microbial symbiosis underpins the survival and prosperity of insects through multiple means. The brown-winged green stinkbug Plautia stali, which is notorious as an agricultural pest and utilized as an experimental model insect, harbors a bacterial symbiont Pantoea in a posterior part of the midgut, which is essential for the host's development and reproduction.

Complete genome of the mutualistic symbiont " Carsonella ruddii" from a Japanese island strain of the Asian citrus psyllid .

The complete genome, 173,958 bp in size, of " Carsonella ruddii" DC-OKEB1 an obligate bacterial endosymbiont of the Asian citrus psyllid , was determined. The genome sequence provides valuable information for comparative and evolutionary aspects of the intimate insect-microbe mutualism.

Complete genome of the mutualistic symbiont " Nardonella sp." Pin-AIST from the black hard weevil .

The complete genome, 226,287 bps in size, of " Nardonella sp." Pin-AIST, an obligatory bacterial endosymbiont of the black hard weevil , was sequenced. The extremely reduced endosymbiont genome is specialized for tyrosine synthesis, which contributes to the hardness of the beetle's exoskeleton.

Robust and highly efficient transformation method for a minimal mycoplasma cell.

Unlabelled: Mycoplasmas have been widely investigated for their pathogenicity, as well as for genomics and synthetic biology. Conventionally, transformation of mycoplasmas was not highly efficient, and due to the low transformation efficiency, large amounts of DNA and recipient cells were required for that purpose. Here, we report a robust and highly efficient transformation method for the minimal cell JCVI-syn3B, which was created through streamlining the genome of .

Symbiosis and horizontal gene transfer promote herbivory in the megadiverse leaf beetles.

Beetles that feed on the nutritionally depauperate and recalcitrant tissues provided by the leaves, stems, and roots of living plants comprise one-quarter of herbivorous insect species. Among the key adaptations for herbivory are plant cell wall-degrading enzymes (PCWDEs) that break down the fastidious polymers in the cell wall and grant access to the nutritious cell content. While largely absent from the non-herbivorous ancestors of beetles, such PCWDEs were occasionally acquired via horizontal gene transfer (HGT) or by the uptake of digestive symbionts.

Complete genome of the mutualistic symbiont AIST from a Japanese strain of the pea aphid .

The genome of National Institute of Advanced Industrial Science and Technology (AIST), an obligate bacterial endosymbiont from a Japanese strain of the pea aphid , was determined. The genome sequence provides valuable information for comparative and evolutionary aspects of the intimate insect-microbe mutualism.

Cloning and sequencing analysis of whole genome in yeast.

Cloning and transfer of long-stranded DNA in the size of a bacterial whole genome has become possible by recent advancements in synthetic biology. For the whole genome cloning and whole genome transplantation, bacteria with small genomes have been mainly used, such as mycoplasmas and related species. The key benefits of whole genome cloning include the effective maintenance and preservation of an organism's complete genome within a yeast host, the capability to modify these genome sequences through yeast-based genetic engineering systems, and the subsequent use of these cloned genomes for further experiments.

Intracellularity, extracellularity, and squeezing in the symbiotic organ underpin nurturing and functioning of bacterial symbiont in leaf beetles.

Cassidine leaf beetles are associated with genome-reduced symbiotic bacteria involved in pectin digestion. cells appear to be harbored in paired symbiotic organs located at the foregut-midgut junction either intracellularly or extracellularly, whereas the symbiont is extracellular in the ovary-accessory glands of adult females and during caplet transmission in eggs. However, using fluorescence and electron microscopy, an intracellular symbiotic configuration of was observed in species.

Defensive fungal symbiosis on insect hindlegs.

Tympanal organs as "insect ears" have evolved repeatedly. Dinidorid stinkbugs were reported to possess a conspicuous tympanal organ on female's hindlegs. Here we report an unexpected discovery that the stinkbug's "tympanal organ" is actually a novel symbiotic organ.

Paleocene origin of a streamlined digestive symbiosis in leaf beetles.

Timing the acquisition of a beneficial microbe relative to the evolutionary history of its host can shed light on the adaptive impact of a partnership. Here, we investigated the onset and molecular evolution of an obligate symbiosis between Cassidinae leaf beetles and Candidatus Stammera capleta, a γ-proteobacterium. Residing extracellularly within foregut symbiotic organs, Stammera upgrades the digestive physiology of its host by supplementing plant cell wall-degrading enzymes.

Regulation and remodeling of microbial symbiosis in insect metamorphosis.

Many insects are dependent on microbial mutualists, which are often harbored in specialized symbiotic organs. Upon metamorphosis, insect organs are drastically reorganized. What mechanism regulates the remodeling of the symbiotic organ upon metamorphosis? How does it affect the microbial symbiont therein? Here, we addressed these fundamental issues of symbiosis by experimentally manipulating insect metamorphosis.

Complete genomes of mutualistic bacterial co-symbionts " Sulcia muelleri" and " Nasuia deltocephalinicola" of the rice green leafhopper .

The genomes of obligate bacterial co-symbionts of the green rice leafhopper , which is notorious as an agricultural pest, were determined. The streamlined genomes of " Sulcia muelleri" and " Nasuia deltocephalinicola" exhibited complementary metabolic pathways for synthesizing essential nutrients that contribute to host adaptation.

Cuticle supplementation and nitrogen recycling by a dual bacterial symbiosis in a family of xylophagous beetles.

Many insects engage in stable nutritional symbioses with bacteria that supplement limiting essential nutrients to their host. While several plant sap-feeding Hemipteran lineages are known to be simultaneously associated with two or more endosymbionts with complementary biosynthetic pathways to synthesize amino acids or vitamins, such co-obligate symbioses have not been functionally characterized in other insect orders. Here, we report on the characterization of a dual co-obligate, bacteriome-localized symbiosis in a family of xylophagous beetles using comparative genomics, fluorescence microscopy, and phylogenetic analyses.

Mechanisms Underpinning Morphogenesis of a Symbiotic Organ Specialized for Hosting an Indispensable Microbial Symbiont in Stinkbugs.

Microbial mutualists are pivotal for insect adaptation, which often entails the evolution of elaborate organs for symbiosis. Addressing what mechanisms underpin the development of such organs is of evolutionary interest. Here, we investigated the stinkbug Plautia stali, whose posterior midgut is transformed into a specialized symbiotic organ.

as facultative bacterial symbionts of stinkbugs.

Many insects are associated with facultative symbiotic bacteria, and their infection prevalence provides an important clue to understand the biological impact of such microbial associates. Here we surveyed diverse stinkbugs representing 13 families, 69 genera, 97 species and 468 individuals for infection. Diagnostic PCR detection revealed that 4 families (30.

Host's demand for essential amino acids is compensated by an extracellular bacterial symbiont in a hemipteran insect model.

Plant sap is a nutritionally unbalanced diet that constitutes a challenge for insects that feed exclusively on it. Sap-sucking hemipteran insects generally overcome this challenge by harboring beneficial microorganisms in their specialized symbiotic organ, either intracellularly or extracellularly. Genomic information of these bacterial symbionts suggests that their primary role is to supply essential amino acids, but empirical evidence has been virtually limited to the intracellular symbiosis between aphids and .