Evolutionary dynamics of mushroom body Kenyon cell types in hymenopteran brains from multifunctional type to functionally specialized types.

Evolutionary dynamics of diversification of brain neuronal cell types that have underlain behavioral evolution remain largely unknown. Here, we compared transcriptomes and functions of Kenyon cell (KC) types that compose the mushroom bodies between the honey bee and sawfly, a primitive hymenopteran insect whose KCs likely have the ancestral properties. Transcriptome analyses show that the sawfly KC type shares some of the gene expression profile with each honey bee KC type, although unique gene expression profiles have also been acquired in each honey bee KC type.

Effects of Functional Depletion of on Male Development in the Sawfly, .

The () gene, which encodes a transcription factor, regulates sexual differentiation in insects. Sex-specific splicing of occurs to yield male- and female-specific isoforms, which promote male and female development, respectively. Thus, functional disruption of leads to an intersexual phenotype in both sexes.

Correction to: Establishment and characterization of novel cell lines derived from six lepidopteran insects collected in the field.

This article was originally published with the final word of the title, "field", omitted.

Sawfly Genomes Reveal Evolutionary Acquisitions That Fostered the Mega-Radiation of Parasitoid and Eusocial Hymenoptera.

The tremendous diversity of Hymenoptera is commonly attributed to the evolution of parasitoidism in the last common ancestor of parasitoid sawflies (Orussidae) and wasp-waisted Hymenoptera (Apocrita). However, Apocrita and Orussidae differ dramatically in their species richness, indicating that the diversification of Apocrita was promoted by additional traits. These traits have remained elusive due to a paucity of sawfly genome sequences, in particular those of parasitoid sawflies.

Establishment and characterization of novel cell lines derived from six lepidopteran insects collected in the field.

Insect cell lines are used to study cellular interactions and gene functions in vitro in several research areas. However, suitable cell lines for experiments are not always available, especially in non-model species. Here, we established novel cell lines derived from fat bodies of six lepidopteran insects: Cydia kurokoi (named NARO-Cyku), Cephonodes hylas (NARO-Cehy), Haritalodes basipunctalis (NARO-Haba), Theretra oldenlandiae (NARO-Thol), Lymantria dispar (NARO-Lydi), and Hyphantria cunea (NARO-Hycu) collected in the field.

Ontogeny of Cheliped Laterality and Mechanisms of Reversal of Handedness in the Durophagous Gazami Crab, .

The paired claws in Gazami crabs, , are bilaterally asymmetrical, and asymmetry is remarkable on the distal two segments of the first pereiopod, that is, the dactylus and propodus. Shells are exclusively cracked by use of the right chela, representing handedness. In Gazami crabs, handedness is reversed after autotomy of the right chela.

Diversity and function of multicopper oxidase genes in the stinkbug Plautia stali.

Multicopper oxidase (MCO) genes comprise multigene families in bacteria, fungi, plants and animals. Two families of MCO genes, MCO1 (laccase1) and MCO2 (laccase2), are conserved among diverse insects and relatively well-characterized, whereas additional MCO genes, whose biological functions have been poorly understood, are also found in some insects. Previous studies reported that MCO1 participates in gut immunity and MCO2 plays important roles in cuticle sclerotization and pigmentation of insects.

Wing vein development in the sawfly Athalia rosae is regulated by spatial transcription of Dpp/BMP signaling components.

Wing venation among insects serves as an excellent model to address how diversified patterns are produced. Previous studies suggest that evolutionarily conserved Decapentaplegic (Dpp)/Bone Morphogenetic Protein (BMP) signal plays a critical role in wing vein development in the dipteran Drosophila melanogaster and the hymenopteran sawfly Athalia rosae. In sawfly, dpp is ubiquitously expressed in the wing during prepupal stages, but Dpp/BMP signal is localized in the future vein cells.

Malaria infectivity of xanthurenic acid-deficient anopheline mosquitoes produced by TALEN-mediated targeted mutagenesis.

Anopheline mosquitoes are major vectors of malaria parasites. When the gametocytes of the malaria parasite are transferred from a vertebrate to mosquitoes, they differentiate into gametes, and are fertilized in the midguts of mosquitoes. Xanthurenic acid (XA), a waste product of the ommochrome synthesis pathway, has been shown to induce exflagellation during microgametogenesis in vitro; however, it currently remains unclear whether endogenous XA affects the infectivity of anopheline mosquitoes to malaria parasites in vivo due to the lack of appropriate experimental systems such as a XA-deficient line.

Identification and functional characterization of the sex-determining gene in the sawfly, (Hymenoptera: Tenthredinidae).

Sexual fate of the sawfly,  (Hymenoptera: Tenthredinidae) is determined by the complementary sex determination (CSD) mechanism as is the case in honeybees. However, to date, genes involved in sex determination have not been identified in this species. In this study, we attempted to identify orthologs of - (), (), and () from the .

Wolbachia infections of the butterfly Eurema mandarina interfere with embryonic development of the sawfly Athalia rosae.

Although maternally transmitted microorganisms such as Wolbachia are well known to have a variety of effects on the reproduction of diverse insect species, little is known about the underlying mechanisms of actions. Artificial transfer of Wolbachia between taxonomically distant host species may provide insights into Wolbachia-induced manipulations of hosts. Here we performed a cross-order transfer of feminizing Wolbachia derived from a butterfly, Eurema mandarina.

The boule gene is essential for spermatogenesis of haploid insect male.

boule (bol), a member of the Deleted in Azoospermia (DAZ) gene family plays an important role in meiosis (reductional maturation divisions) in a spermatogenesis-specific manner in animals by regulating translation of the downstream cell division cycle 25 (cdc25) phosphatase mRNA. Orthologues of bol are conserved among animals and found in the genomes of hymenopteran insects, in which the general mode of reproduction is haplodiploidy: female is diploid and male is haploid. In this mode of reproduction, haploid males produce haploid sperm through non-reductional maturation divisions.

Insights into the molecular mechanisms underlying diversified wing venation among insects.

Insect wings are great resources for studying morphological diversities in nature as well as in fossil records. Among them, variation in wing venation is one of the most characteristic features of insect species. Venation is therefore, undeniably a key factor of species-specific functional traits of the wings; however, the mechanism underlying wing vein formation among insects largely remains unexplored.

Artificial activation of mature unfertilized eggs in the malaria vector mosquito, Anopheles stephensi (Diptera, Culicidae).

In the past decade, many transgenic lines of mosquitoes have been generated and analyzed, whereas the maintenance of a large number of transgenic lines requires a great deal of effort and cost. In vitro fertilization by an injection of cryopreserved sperm into eggs has been proven to be effective for the maintenance of strains in mammals. The technique of artificial egg activation is a prerequisite for the establishment of in vitro fertilization by sperm injection.

Dpp/BMP transport mechanism is required for wing venation in the sawfly Athalia rosae.

The pattern of wing venation varies considerably among different groups of insects and has been used as a means of species-specific identification. However, little is known about how wing venation is established and diversified among insects. The decapentaplegic (Dpp)/bone morphogenetic protein (BMP) signaling pathway plays a critical role in wing vein formation during the pupal stages in Drosophila melanogaster.

A survey of the effectiveness of non-cell autonomous RNAi throughout development in the sawfly, Athalia rosae (Hymenoptera).

RNA interference (RNAi) is a powerful and convenient tool not only for functional analysis of specific genes, but also for large-scale screening of gene function in insects; however, reports on its efficiency throughout development in a single species are limited. We demonstrate here that non-cell autonomous RNAi by injection of double-stranded RNA (dsRNA) knocks down targeting genes in most developmental stages in the sawfly, Athalia rosae. Injection of dsRNA targeting the green fluorescence protein (gfp) gene into eggs of a transgenic strain carrying the constitutively expressing gfp gene resulted in the absence of GFP fluorescence during embryogenesis, while a portion of the gfp dsRNA-injected embryos began exhibiting GFP fluorescence at late embryogenesis.

Characterization of abdominal appendages in the sawfly, Athalia rosae (Hymenoptera), by morphological and gene expression analyses.

Larvae of the sawfly, Athalia rosae, have remarkable abdominal prolegs. We analyzed the morphogenesis of appendages and the expression of decapentaplegic and Distal-less genes during embryonic development to characterize the origin of prolegs. Proleg primordia in abdominal segments A1-A9 appeared shortly after the inner lobes (endites) of gnathal appendages were formed.

Involvement of Mos-MEK-MAPK pathway in cytostatic factor (CSF) arrest in eggs of the parthenogenetic insect, Athalia rosae.

Extensive survey of meiotic metaphase II arrest during oocyte maturation in vertebrates revealed that the mitogen-activated protein kinase (MAPK) pathway regulated by the c-mos proto-oncogene product, Mos, has an essential role in cytostatic activity, termed cytostatic factor (CSF). In contrast, little is known in invertebrates in which meiotic arrest occurs in most cases at metaphase I (MI arrest). A parthenogenetic insect, the sawfly Athalia rosae, in which artificial egg activation is practicable, has advantages to investigate the mechanisms of MI arrest.

Expression pattern of Bombyx vasa-like (BmVLG) protein and its implications in germ cell development.

Germ cell development in the silkworm Bombyx mori is interesting in that the species has no recognizable germ plasm, and its germ cells appear first on the ventral side of the embryo, not on the posterior pole as in Drosophila melanogaster. We previously reported the isolation of a vasa homologue (BmVLG) from B. mori and revealed the specific expression of transcript in the germ cells.

Isolation of white gene orthologue of the sawfly, Athalia rosae (Hymenoptera) and its functional analysis using RNA interference.

We isolated and characterized the white gene orthologue of the sawfly, Athalia rosae (Hymenoptera). The A. rosae white (Ar white) cDNA cloned was 2058-bp long encoding 685 amino acids in a single open reading frame (ORF).

Cloning of a decapentaplegic orthologue from the sawfly, Athalia rosae (Hymenoptera), and its expression in the embryonic appendages.

The cDNA of a decapentaplegic (dpp) orthologue from the sawfly, Athalia rosae (Hymenoptera), was cloned and characterized. The clone (Ar dpp) was 2,566 bp long and encoded 395 amino acids in a single open reading frame. Genomic Southern blotting showed that Ar dpp is a single copy gene.

Purification and cDNA cloning of the ovigerous-hair stripping substance (OHSS) contained in the hatch water of an estuarine crab Sesarma haematocheir.

The egg attachment system of an estuarine crab Sesarma haematocheir is formed on the maternal ovigerous hairs just after egg laying, and slips off these hairs just after hatching. The stripping is caused by an active factor that we call OHSS (ovigerous-hair stripping substance), which is released by the embryo upon hatching. OHSS was purified, and its active form had a molecular mass of 25 kDa.

Cloning and characterization of Acmar1, a mariner-like element in the asiatic honey bee, Apis cerana japonica (Hymenoptera, Apocrita).

A mariner-like element was cloned from the genome of the Asiatic honey bee, Apis cerana japonica (Hymenoptera, Apocrita). The (composite) clone, named Acmar1, was 1,378 bp long, and encoded 336 amino acids corresponding to a transposase-like putative polypeptide in a single open reading frame. The D,D(34)D motif, the catalytic domain of the mariner transposase, was present, although there was a deletion of five amino acid residues within it as compared with the active transposase in Drosophila mauritiana.