Neo-sex Chromosomes in the Monarch Butterfly, Danaus plexippus

We report the discovery of a neo-sex chromosome in the monarch butterfly, Danaus plexippus, and several of its close relatives. Z-linked scaffolds in the D. plexippus genome assembly were identified via sex-specific differences in Illumina sequencing coverage. Additionally, a majority of the D. plexippus genome assembly was assigned to chromosomes based on counts of one-to-one orthologs relative to the butterfly Melitaea cinxia (with replication using two other lepidopteran species), in which genome scaffolds have been mapped to linkage groups. Sequencing coverage-based assessments of Z linkage combined with homology-based chromosomal assignments provided strong evidence for a Z-autosome fusion in the Danaus lineage, involving the autosome homologous to chromosome 21 in M. cinxia. Coverage analysis also identified three notable assembly errors resulting in chimeric Z-autosome scaffolds. Cytogenetic analysis further revealed a large W chromosome that is partially euchromatic, consistent with being a neo-W chromosome. The discovery of a neo-Z and the provisional assignment of chromosome linkage for >90% of D. plexippus genes lays the foundation for novel insights concerning sex chromosome evolution in this female-heterogametic model species for functional and evolutionary genomics

A conserved role of the duplicated <i>Masculinizer</i> gene in sex determination of the Mediterranean flour moth, <i>Ephestia kuehniella</i>

Sex determination in the silkworm, Bombyx mori, is based on Feminizer (Fem), a W-linked Fem piRNA that triggers female development in WZ individuals, and the Z-linked Masculinizer (Masc), which initiates male development and dosage compensation in ZZ individuals. While Fem piRNA is missing in a close relative of B. mori, Masc determines sex in several representatives of distant lepidopteran lineages. We studied the molecular mechanisms of sex determination in the Mediterranean flour moth, Ephestia kuehniella (Pyralidae). We identified an E. kuehniella Masc ortholog, EkMasc, and its paralog resulting from a recent duplication, EkMascB. Both genes are located on the Z chromosome and encode a similar Masc protein that contains two conserved domains but has lost the conserved double zinc finger domain. We developed PCR-based genetic sexing and demonstrated a peak in the expression of EkMasc and EkMascB genes only in early male embryos. Simultaneous knock-down experiments of both EkMasc and EkMascB using RNAi during early embryogenesis led to a shift from male- to female-specific splicing of the E. kuehniella doublesex gene (Ekdsx), their downstream effector, in ZZ embryos and resulted in a strong female-biased sex-ratio. Our results thus confirmed the conserved role of EkMasc and/or EkMascB in masculinization. We suggest that the C-terminal proline-rich domain, we have identified in all functionally confirmed Masc proteins, in conjunction with the masculinizing domain, is important for transcriptional regulation of sex determination in Lepidoptera. The function of the Masc double zinc finger domain is still unknown, but appears to have been lost in E. kuehniella

Dynamic karyotype evolution and unique sex determination systems in Leptidea wood white butterflies

[Background] Chromosomal rearrangements have the potential to limit the rate and pattern of gene flow within and between species and thus play a direct role in promoting and maintaining speciation. Wood white butterflies of the genus Leptidea are excellent models to study the role of chromosome rearrangements in speciation because they show karyotype variability not only among but also within species. In this work, we investigated genome architecture of three cryptic Leptidea species (L. juvernica, L. sinapis and L. reali) by standard and molecular cytogenetic techniques in order to reveal causes of the karyotype variability.[Results] Chromosome numbers ranged from 2n = 85 to 91 in L. juvernica and 2n = 69 to 73 in L. sinapis (both from Czech populations) to 2n = 51 to 55 in L. reali (Spanish population). We observed significant differences in chromosome numbers and localization of cytogenetic markers (rDNA and H3 histone genes) within the offspring of individual females. Using FISH with the (TTAGG) n telomeric probe we also documented the presence of multiple chromosome fusions and/or fissions and other complex rearrangements. Thus, the intraspecific karyotype variability is likely due to irregular chromosome segregation of multivalent meiotic configurations. The analysis of female meiotic chromosomes by GISH and CGH revealed multiple sex chromosomes: W1W2W3Z1Z2Z3Z4 in L. juvernica, W1W2W3Z1Z2Z3 in L. sinapis and W1W2W3W4Z1Z2Z3Z4 in L. reali.[Conclusions] Our results suggest a dynamic karyotype evolution and point to the role of chromosomal rearrangements in the speciation of Leptidea butterflies. Moreover, our study revealed a curious sex determination system with 3–4 W and 3–4 Z chromosomes, which is unique in the Lepidoptera and which could also have played a role in the speciation process of the three Leptidea species.This research was funded by Grant 14-22765S of the Czech Science Foundation, Grant IAA600960925 of the Grant Agency of The Czech Academy of Sciences, Grant 063/2012/P of the Grant Agency of the University of South Bohemia and Grant CGL2013-48277-P from the Spanish Ministerio de Economía y Competitividad. JŠ and AV were supported by Grant 052/2013/P of the Grant Agency of the University of South Bohemia, VD by a Marie Curie International Outgoing Fellowship within the 7th European Community Framework Programme (project no. 625997), PN by Grant 14-35819P of the Czech Science Foundation and KS by JSPS 23380030 grant and JSPS Excellent Young Researchers Overseas Visit Program (21–7147).Peer reviewe

Monetary Exit and Fiscal Spillovers

The aftermath of the Global financial crisis has seen two types of monetary policy concerns. Some economists (e.g. Paul Krugman) worry primarily about possible deflation caused by a secular stagnation. In contrast, others (e.g. John Taylor) worry about excessively high inflation caused by quantitative easing and monetization of fiscal imbalances. We show that some countries should fear both - deflation in the short term and high inflation in the long term - whereas some countries are unlikely to experience either. This is done in a game theoretic framework with dynamic leadership (stochastic revisions of actions). Such framework enables us to examine strategic monetary-fiscal interactions as well as policymakers' incomplete information about the economic recovery (such as during 2010-2014). Our empirical section then quantifies indices of monetary and fiscal leadership for high-income countries to assess their deflationary/inflationary prospects. It is shown, for example, that undesirable departures from price stability, both in the short term and long term, are much more likely in the United States and Japan than in Australia or New Zealand

Monetary Exit and Fiscal Spillovers

The aftermath of the Global financial crisis has seen two types of monetary policy concerns. Some economists (e.g. Paul Krugman) worry primarily about possible deflation caused by a secular stagnation. In contrast, others (e.g. John Taylor) worry about excessively high inflation caused by quantitative easing and monetization of fiscal imbalances. We show that some countries should fear both - deflation in the short term and high inflation in the long term - whereas some countries are unlikely to experience either. This is done in a game theoretic framework with dynamic leadership (stochastic revisions of actions). Such framework enables us to examine strategic monetary-fiscal interactions as well as policymakers' incomplete information about the economic recovery (such as during 2010-2014). Our empirical section then quantifies indices of monetary and fiscal leadership for high-income countries to assess their deflationary/inflationary prospects. It is shown, for example, that undesirable departures from price stability, both in the short term and long term, are much more likely in the United States and Japan than in Australia or New Zealand

Genome sequence and silkomics of the spindle ermine moth, Yponomeuta cagnagella, representing the early diverging lineage of the ditrysian Lepidoptera

Many lepidopteran species produce silk, cocoons, feeding tubes, or nests for protection from predators and parasites for caterpillars and pupae. Yet, the number of lepidopteran species whose silk composition has been studied in detail is very small, because the genes encoding the major structural silk proteins tend to be large and repetitive, making their assembly and sequence analysis difficult. Here we have analyzed the silk of Yponomeuta cagnagella, which represents one of the early diverging lineages of the ditrysian Lepidoptera thus improving the coverage of the order. To obtain a comprehensive list of the Y. cagnagella silk genes, we sequenced and assembled a draft genome using Oxford Nanopore and Illumina technologies. We used a silk-gland transcriptome and a silk proteome to identify major silk components and verified the tissue specificity of expression of individual genes. A detailed annotation of the major genes and their putative products, including their complete sequences and exon-intron structures is provided. The morphology of silk glands and fibers are also shown. This study fills an important gap in our growing understanding of the structure, evolution, and function of silk genes and provides genomic resources for future studies of the chemical ecology of Yponomeuta species

Optimized design of source energy for manufacturing machine by digital numerical control

The quality of the power supplied to the machining center is a key factor in determining the accuracy of the machine’s operation. The precision of the machining center is to ensure that the spindle accuracy is less than 3 microns. This study proposes a digital numerical control system to control the quality of the power supply and control the accuracy of the spindle axis of the machining center to monitor the measurement results in real time. The computer vision system is set up according to the artificial intelligent (AI) technique to recognize human face objects and control the position of the processor respectively on each line. The online measurement system follows the digital numerical control (DNC) system applied at each processing line, measuring product dimensions, measuring conditions for setting up machining tools, and measuring machine coordinates. The system operates fully automatically, eliminating dependence on operator skill, and facilitating operation in control of machining conditions. Improve machining center operator satisfaction. After implementation of the improvement options, total cost down 1.740 USD per year, the monthly repair cost due to broken drill, spindle alignment decreased from $5000 to$3,300 per month. The scrap rate related to the hole size decreased from 0.47% to 0.23% (cost down $35 per month). Downtime for repair reduced from 20 hours per month to 7.5 hours per month (cost down$10 per month). Broken drill rate was reduced from 0.20% to 0.06% (cost down $100 per month).Web of Science201103211030