Zygosity-based sex determination in a butterfly drives hypervariability of .

Nature has devised many ways of producing males and females. Here, we report on a previously undescribed mechanism for Lepidoptera that functions without a female-specific gene. The number of alleles or allele heterozygosity in a single Z-linked gene () is the primary sex-determining switch in butterflies.

Chromosome analysis and the occurrence of B chromosomes in fish parasite Acanthocephalus anguillae (Palaeacanthocephala: Echinorhynchida).

The cytogenetics of Acanthocephala is a neglected area in the study of this group of endoparasites. Chromosome number and/or karyotypes are known for only 12 of the 1,270 described species, and molecular cytogenetic data are limited to rDNA mapping in two species. The standard karyological technique and mapping of 18S rRNA and H3 histone genes on the chromosomes of Acanthocephalus anguillae individuals from three populations, one of which originated from the unfavorable environmental conditions of the Zemplínska Šírava reservoir in eastern Slovakia, were applied for the first time.

Fecundity, in vitro early larval development and karyotype of the zoonotic nematode Anisakis pegreffii.

The in vitro life cycle of zoonotic helminths is an essential tool for -omic translational studies focused on disease control and treatment. Anisakiosis is an emerging zoonosis contracted by the ingestion of raw or undercooked fish infected with the third stage larvae (L3) of two sibling species Anisakis simplex sensu stricto (s.s.

Masculinizer gene controls male sex determination in the codling moth, Cydia pomonella.

The molecular mechanisms of sex determination in moths and butterflies (Lepidoptera) with female heterogamety (WZ/ZZ) are poorly understood, except in the silkworm Bombyx mori. However, the Masculinizer (Masc) gene that controls male development and dosage compensation in B. mori, appears to be conserved in Lepidoptera, as its masculinizing function was recently confirmed in several moth species.

Accumulation of retrotransposons contributes to W chromosome differentiation in the willow beauty Peribatodes rhomboidaria (Lepidoptera: Geometridae).

The W chromosome of Lepidoptera is typically gene-poor, repeat-rich and composed of heterochromatin. Pioneering studies investigating this chromosome reported an abundance of mobile elements. However, the actual composition of the W chromosome varies greatly between species, as repeatedly demonstrated by comparative genomic hybridization (CGH) or fluorescence in situ hybridization (FISH).

On the Origin of Neo-Sex Chromosomes in the Neotropical Dragonflies and (Aeshnidae, Odonata).

Odonata have holokinetic chromosomes. About 95% of species have an XX/X0 sex chromosome system, with heterogametic males. There are species with neo-XX/neo-XY sex chromosomes resulting from an X chromosome/autosome fusion.

A step forward in the genome characterization of the sugarcane borer, Diatraea saccharalis: karyotype analysis, sex chromosome system and repetitive DNAs through a cytogenomic approach.

Moths of the family Crambidae include a number of pests that cause economic losses to agricultural crops. Despite their economic importance, little is known about their genome architecture and chromosome evolution. Here, we characterized the chromosomes and repetitive DNA of the sugarcane borer Diatraea saccharalis using a combination of low-pass genome sequencing, bioinformatics, and cytogenetic methods, focusing on the sex chromosomes.

Degenerated, Undifferentiated, Rearranged, Lost: High Variability of Sex Chromosomes in Geometridae (Lepidoptera) Identified by Sex Chromatin.

Sex chromatin is a conspicuous body that occurs in polyploid nuclei of most lepidopteran females and consists of numerous copies of the W sex chromosome. It is also a cytogenetic tool used to rapidly assess the W chromosome presence in Lepidoptera. However, certain chromosomal features could disrupt the formation of sex chromatin and lead to the false conclusion that the W chromosome is absent in the respective species.

Large-scale comparative analysis of cytogenetic markers across Lepidoptera.

Fluorescence in situ hybridization (FISH) allows identification of particular chromosomes and their rearrangements. Using FISH with signal enhancement via antibody amplification and enzymatically catalysed reporter deposition, we evaluated applicability of universal cytogenetic markers, namely 18S and 5S rDNA genes, U1 and U2 snRNA genes, and histone H3 genes, in the study of the karyotype evolution in moths and butterflies. Major rDNA underwent rather erratic evolution, which does not always reflect chromosomal changes.

Evolutionary pattern of karyotypes and meiosis in pholcid spiders (Araneae: Pholcidae): implications for reconstructing chromosome evolution of araneomorph spiders.

Background: Despite progress in genomic analysis of spiders, their chromosome evolution is not satisfactorily understood. Most information on spider chromosomes concerns the most diversified clade, entelegyne araneomorphs. Other clades are far less studied.

The Role of Satellite DNAs in Genome Architecture and Sex Chromosome Evolution in Crambidae Moths.

Tandem repeats are important parts of eukaryotic genomes being crucial e.g., for centromere and telomere function and chromatin modulation.

Patterns of Sex Chromosome Differentiation in Spiders: Insights from Comparative Genomic Hybridisation.

Spiders are an intriguing model to analyse sex chromosome evolution because of their peculiar multiple X chromosome systems. Y chromosomes were considered rare in this group, arising after neo-sex chromosome formation by X chromosome-autosome rearrangements. However, recent findings suggest that Y chromosomes are more common in spiders than previously thought.

Absence of W Chromosome in Psychidae Moths and Implications for the Theory of Sex Chromosome Evolution in Lepidoptera.

Moths and butterflies (Lepidoptera) are the largest group with heterogametic females. Although the ancestral sex chromosome system is probably Z0/ZZ, most lepidopteran species have the W chromosome. When and how the W chromosome arose remains elusive.

Sex Chromosomes of the Iconic Moth (Lepidoptera, Geometridae) and Its Congener .

The magpie moth, , is an iconic species in which female heterogamety was discovered at the beginning of the 20th century. However, the sex chromosomes of this species have not yet been cytologically identified. We describe the sex chromosomes of and its congener, .

New Insights into the Evolution of the W Chromosome in Lepidoptera.

Moths and butterflies (Lepidoptera) represent the most diverse group of animals with heterogametic females. Although the vast majority of species has a WZ/ZZ (female/male) sex chromosome system, it is generally accepted that the ancestral system was Z/ZZ and the W chromosome has evolved in a common ancestor of Tischeriidae and Ditrysia. However, the lack of data on sex chromosomes in lower Lepidoptera has prevented a formal test of this hypothesis.

W-enriched satellite sequence in the Indian meal moth, Plodia interpunctella (Lepidoptera, Pyralidae).

The W chromosome of most lepidopteran species represents the largest heterochromatin entity in the female genome. Although satellite DNA is a typical component of constitutive heterochromatin, there are only a few known satellite DNAs (satDNAs) located on the W chromosome in moths and butterflies. In this study, we isolated and characterized new satDNA (PiSAT1) from microdissected W chromosomes of the Indian meal moth, Plodia interpunctella.

CpSAT-1, a transcribed satellite sequence from the codling moth, Cydia pomonella.

Satellite DNA (satDNA) is a non-coding component of eukaryotic genomes, located mainly in heterochromatic regions. Relevance of satDNA began to emerge with accumulating evidence of its potential yet hardly comprehensible role that it can play in the genome of many organisms. We isolated the first satDNA of the codling moth (Cydia pomonella, Tortricidae, Lepidoptera), a species with holokinetic chromosomes and a single large heterochromatic element, the W chromosome in females.