Karyological analysis of Acanthocephalus ranae (Echinorhynchida): expanding the cytogenetic knowledge in acanthocephalans

By

Orosová, Martina
Marková, Anna

Type

Article

Date of Publication

2025-6-25

Original Publication

ZooKeys

Volume

1243

Pages

173--189

Subjects

Acanthocephala , chromosome , Differential staining , fluorescence in situ hybridization , histone H3 , histone H3 , histone H3 , karyotype , ribosomal genes

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.1243.153591

 

Abstract

This study presents the first comprehensive cytogenetic analysis of the common amphibian parasite Acanthocephalus ranae. A combination of classical cytogenetic methods and molecular techniques, including the fluorescence in situ hybridization (FISH) mapping of ribosomal and histone H3, was conducted. The karyotype consisted of three metacentric autosomes and either one submetacentric X chromosome in males or two submetacentric X chromosomes in females, resulting in a chromosome number of 2n = 7/8 (male/female). FISH mapping revealed that the ribosomal genes are located separately, with 18S rDNA situated on the X chromosomes and 5S rDNA on chromosome pair No. 3. The hybridization signals of histone H3 genes were dispersed across all chromosomes without any discernible pattern. Additionally, differential staining identified GC-rich heterochromatin at the ends of all chromosomes. These findings significantly expand the limited karyotypic data available for acanthocephalan parasites, of which the karyotype and/or chromosome number is known for only 1% of described species, and molecular cytogenetic techniques have been applied in just four species. The karyotype characteristics of A. ranae were also compared with other cytogenetically described thorny-headed worms within the order Echinorhynchida.