A cascade of 20-hydroxyecdysone-mediated gene expression and repression initiates larva-to-pupa metamorphosis. We recently showed that two transcription factors, BmPOUM2 and BmβFTZ-F1, bind to the cis-regulatory elements in the promoter of the gene coding for cuticle protein, BmWCP4, and regulate its expression during Bombyx mori metamorphosis. Here we show that downregulation of BmPOUM2 expression by RNA interference during the wandering stage resulted in failure to complete metamorphosis. The thorax epidermis of RNA interference-treated larvae became transparent, wing disc growth and differentiation were arrested, and the larvae failed to spin cocoons. Quantitative real-time PCR analysis showed that expression of the genes coding for pupal-specific wing cuticle proteins BmWCP1, BmWCP2, BmWCP3, BmWCP4, BmWCP5, BmWCP6, BmWCP8, and BmWCP9 were down-regulated in BmPOUM2 dsRNA-treated animals, whereas overexpression of BmPOUM2 protein increased the expression of BmWCP4, BmWCP5, BmWCP6, BmWCP7, and BmWCP8. Pull-down assays, far-Western blot, and electrophoretic mobility shift assay showed that the BmPOUM2 protein interacted with another homeodomain transcription factor, BmAbd-A, to induce the expression of BmWCP4. Immunohistochemical localization of BmPOUM2, BmAbd-A, and BmWCP4 proteins revealed that BmAbd-A and BmPOUM2 proteins are colocalized in the wing disc cell nuclei, whereas BmWCP4 protein is localized in the cytoplasm. Together these data suggest that BmPOUM2 interacts with the homeodomain transcription factor BmAbd-A and regulates the expression of BmWCP4 and probably other BmWCPs to complete the larva-topupa transformation. Although homeodomain proteins are known to regulate embryonic development, this study showed that these proteins also regulate metamorphosis.ecdysone | juvenile hormone | molt | pupation P reviously, we reported that 20-hydroxyecdysone (20E) induced the expression of the transcription factors BmβFTZ-F1 and BmPOUM2 that bind the cis-response elements (CREs) of the wing disc cuticle protein gene, BmWCP4, and activate its expression, resulting in the synthesis of the cuticle protein in the pupal wing discs during metamorphosis (1). However, the mechanism of regulation of the pupal-and epidermis-specific expression of gene coding for BmWCP4 by BmPOUM2 is not known.Homeotic or Hox genes determine segment morphology and appendage number in arthropods. These genes also regulate vertebra morphology as well as limb and central nervous system patterning in vertebrates (2, 3). A major characteristic of Hox genes is the presence of a highly conserved 180-base pair DNA binding motif (homeodomain). The majority of the Hox gene research focused on embryonic patterning in the fruit fly, Drosophila melanogaster. In this insect, Hox genes regulate the identity of body segments during embryogenesis. POU is a subclass of Hox genes and consists of three eukaryotic nuclear transcription factors (Pit,

Background: The phylogeny of the Orthoptera was analyzed based on 6 datasets from 47 orthopteran mitochondrial genomes (mitogenomes). The phylogenetic signals in the mitogenomes were rigorously examined under analytical regimens of maximum likelihood (ML) and Bayesian inference (BI), along with how gene types and different partitioning schemes influenced the phylogenetic reconstruction within the Orthoptera. The monophyly of the Orthoptera and its two suborders (Caelifera and Ensifera) was consistently recovered in the analyses based on most of the datasets we selected, regardless of the optimality criteria.

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With the aim of finding natural anthelmintic agents against Dactylogyrus intermedius (Monogenea) in goldfish (Carassius auratus), 26 plants were screened for antiparasitic properties using in vivo anthelmintic efficacy assay. The results showed that Caesalpinia sappan, Lysima chiachristinae, Cuscuta chinensis, Artemisia argyi, and Eupatorium fortunei were found to have 100% anthelmintic efficacy at 125, 150, 225, 300, and 500 mg L(-1) after 48 h of exposure. Crude extract of the five plants were further partitioned with petroleum ether, chloroform, ethyl acetate, methanol, and water to obtain anthelmintically active fractions with various polarity. Among these fractions tested, the ethyl acetate extract of L. chiachristinae was found to be the most effective with a 50% effective concentration (EC50) value of 5.1 mg/L after 48 h of exposure. This was followed by ethyl acetate extract of C. chinensis (48 h-EC50 = 8.5 mg L(-1)), chloroform extracts of C. sappan (48 h-EC50 = 15.6 mg L(-1)), methanol extract of C. chinensis (48 h-EC50 = 15.9 mg L(-1)), and chloroform and petroleum ether extract of L. chiachristinae (EC50 values of 17.2 and 21.1 mg/L, respectively), suggesting that these plants, as well as the active fractions, provide potential sources of botanic drugs for the control of D. intermedius in aquaculture.