Affiliation:
1. Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia
2. Department of Karyosystematics, Zoological Institute of Russian Academy of Sciences, Universitetskaya nab. 1, St. Petersburg 199034, Russia
Abstract
Butterfly chromosomes are holocentric, i.e., lacking a localized centromere. Potentially, this can lead to rapid karyotypic evolution through chromosome fissions and fusions, since fragmented chromosomes retain kinetic activity, while fused chromosomes are not dicentric. However, the actual mechanisms of butterfly genome evolution are poorly understood. Here, we analyzed chromosome-scale genome assemblies to identify structural rearrangements between karyotypes of satyrine butterfly species. For the species pair Erebia ligea–Maniola jurtina, sharing the ancestral diploid karyotype 2n = 56 + ZW, we demonstrate a high level of chromosomal macrosynteny and nine inversions separating these species. We show that the formation of a karyotype with a low number of chromosomes (2n = 36 + ZW) in Erebia aethiops was based on ten fusions, including one autosome–sex chromosome fusion, resulting in a neo-Z chromosome. We also detected inversions on the Z sex chromosome that were differentially fixed between the species. We conclude that chromosomal evolution is dynamic in the satyrines, even in the lineage that preserves the ancestral chromosome number. We hypothesize that the exceptional role of Z chromosomes in speciation may be further enhanced by inversions and sex chromosome–autosome fusions. We argue that not only fusions/fissions but also inversions are drivers of the holocentromere-mediated mode of chromosomal speciation.
Funder
Russian Science Foundation
Subject
Genetics (clinical),Genetics
Reference95 articles.
1. Notes on the mitotic behavior of long chromosomes;Schrader;Cytologia,1935
2. White, M.J.D. (1973). Animal Cytology and Evolution, Cambridge University Press. [3rd ed.].
3. Mandrioli, M., and Manicardi, G.C. (2020). Holocentric chromosomes. PLoS Genet., 16.
4. Repeat-based holocentromeres influence genome architecture and karyotype evolution;Hofstatter;Cell,2022
5. Holocentric chromosomes: Convergent evolution, meiotic adaptations, and genomic analysis;Melters;Chromosome Res.,2012
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