Shared Ancient Sex Chromosomes in Varanids, Beaded Lizards, and Alligator Lizards
Language English Country United States Media print
Document type Comparative Study, Journal Article, Research Support, Non-U.S. Gov't
PubMed
30722046
DOI
10.1093/molbev/msz024
PII: 5307025
Knihovny.cz E-resources
- Keywords
- dosage compensation, homology, molecular sexing, reptiles, sex chromosomes,
- MeSH
- Sex Determination Analysis MeSH
- Lizards genetics MeSH
- Dosage Compensation, Genetic MeSH
- Sex Chromosomes * MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
Sex determination in varanids, Gila monsters, beaded lizards, and other anguimorphan lizards is still poorly understood. Sex chromosomes were reported only in a few species based solely on cytogenetics, which precluded assessment of their homology. We uncovered Z-chromosome-specific genes in varanids from their transcriptomes. Comparison of differences in gene copy numbers between sexes across anguimorphan lizards and outgroups revealed that homologous differentiated ZZ/ZW sex chromosomes are present in Gila monsters, beaded lizards, alligator lizards, and a wide phylogenetic spectrum of varanids. However, these sex chromosomes are not homologous to those known in other amniotes. We conclude that differentiated sex chromosomes were already present in the common ancestor of Anguimorpha living in the early Cretaceous or even in the Jurassic Period, 115-180 Ma, placing anguimorphan sex chromosomes among the oldest known in vertebrates. The analysis of transcriptomes of Komodo dragon (Varanus komodoensis) showed that the expression levels of genes linked to anguimorphan sex chromosomes are not balanced between sexes. Besides expanding our knowledge on vertebrate sex chromosome evolution, our study has important practical relevance for breeding and ecological studies. We introduce the first, widely applicable technique of molecular sexing in varanids, Gila monsters, and beaded lizards, where reliable determination of sex based on external morphology is dubious even in adults.
References provided by Crossref.org
Sex Chromosome Turnovers and Stability in Snakes
Cytogenetic Analysis of Satellitome of Madagascar Leaf-Tailed Geckos
Sex chromosome evolution among amniotes: is the origin of sex chromosomes non-random?
Cytogenetic Evidence for Sex Chromosomes and Karyotype Evolution in Anguimorphan Lizards
Poorly differentiated XX/XY sex chromosomes are widely shared across skink radiation
Evolutionary Variability of W-Linked Repetitive Content in Lacertid Lizards
