Male and female meiosis in the mountain scorpion Zabius fuscus (Scorpiones, Buthidae): Heterochromatin, rDNA and TTAGG telomeric repeats

All cytogenetically studied scorpions present male achiasmatic meiosis and lack heteromorphic sex chromosomes. In contrast, information about female meiosis in scorpions is scarce due to the difficulty of finding meiotic cells. The genus Zabius includes three described species and no chromosome stud...

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Detalles Bibliográficos
Autores: Adilardi, Renzo Sebastián, Ojanguren Affilastro, Andres Alejandro, Mattoni, Camilo Ivan, Mola, Liliana Maria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/7936
Acceso en línea:http://hdl.handle.net/11336/7936
Access Level:acceso abierto
Palabra clave:Holokinetic Chromosomes
Achiasmatic Meiosis
Telomere
Fish
Female Diffuse Stage
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:All cytogenetically studied scorpions present male achiasmatic meiosis and lack heteromorphic sex chromosomes. In contrast, information about female meiosis in scorpions is scarce due to the difficulty of finding meiotic cells. The genus Zabius includes three described species and no chromosome studies have been performed on it until now. We analyzed the constitutive heterochromatin distribution, NORs and telomeric sequences in mitosis and meiosis of males and females of different populations of Zabius fuscus. All specimens presented 2n=18 holokinetic chromosomes that gradually decreased in size. Male meiosis presented nine bivalents and a polymorphism for one reciprocal translocation in one population. Telomeric signals were detected at every terminal region, confirming also the presence of a (TTAGG)n motif in Buthidae. Constitutive heterochromatin was found in three chromosome pairs at a terminal region; moreover, NORs were embedded in the heterochromatic region of the largest pair. Chromosome size and landmarks allowed us to propose the chromosomes involved in the rearrangement. In four females, cells at different prophase I stages were analyzed. We describe a diffuse stage and the presence of ring-shaped bivalents. We discuss the possible origin of these bivalents in the framework of chiasmatic or achiasmatic female meiosis. These results contribute to increase the scarce evidence of female meiosis in scorpions and raise new questions about its mechanism.