1. Cross-Species BAC Mapping Highlights Conservation of Chromosome Synteny across Dragon Lizards (Squamata: Agamidae)
- Author
-
Arthur Georges, Shayer Mahmood Ibney Alam, Tariq Ezaz, Lukáš Kratochvíl, Michail Rovatsos, Tony Gamble, Stephen D. Sarre, Stuart V. Nielsen, Tulyawat Prasongmaneerut, Kornsorn Srikulnath, and Marie Altmanová
- Subjects
0106 biological sciences ,0301 basic medicine ,Chromosomes, Artificial, Bacterial ,Sex Determination Analysis ,Subfamily ,Squamata ,lcsh:QH426-470 ,agamid lizards ,Agamidae ,010603 evolutionary biology ,01 natural sciences ,Article ,Evolution, Molecular ,03 medical and health sciences ,Cytogenetics ,FISH ,evolution ,Genetics ,Animals ,Genetics (clinical) ,Synteny ,Sex Chromosomes ,biology ,synteny ,Chromosome ,BACs ,Lizards ,Snakes ,Sex Determination Processes ,biology.organism_classification ,lcsh:Genetics ,030104 developmental biology ,Evolutionary biology ,Karyotyping ,Microchromosome ,Central bearded dragon ,Amphibolurinae ,Female - Abstract
Dragon lizards (Squamata: Agamidae) comprise about 520 species in six subfamilies distributed across Asia, Australasia and Africa. Only five species are known to have sex chromosomes. All of them possess ZZ/ZW sex chromosomes, which are microchromosomes in four species from the subfamily Amphibolurinae, but much larger in Phrynocephalus vlangalii from the subfamily Agaminae. In most previous studies of these sex chromosomes, the focus has been on Australian species from the subfamily Amphibolurinae, but only the sex chromosomes of the Australian central bearded dragon (Pogona vitticeps) are well-characterized cytogenetically. To determine the level of synteny of the sex chromosomes of P. vitticeps across agamid subfamilies, we performed cross-species two-colour FISH using two bacterial artificial chromosome (BAC) clones from the pseudo-autosomal regions of P. vitticeps. We mapped these two BACs across representative species from all six subfamilies as well as two species of chameleons, the sister group to agamids. We found that one of these BAC sequences is conserved in macrochromosomes and the other in microchromosomes across the agamid lineages. However, within the Amphibolurinae, there is evidence of multiple chromosomal rearrangements with one of the BACs mapping to the second-largest chromosome pair and to the microchromosomes in multiple species including the sex chromosomes of P. vitticeps. Intriguingly, no hybridization signal was observed in chameleons for either of these BACs, suggesting a likely agamid origin of these sequences. Our study shows lineage-specific evolution of sequences/syntenic blocks and successive rearrangements and reveals a complex history of sequences leading to their association with important biological processes such as the evolution of sex chromosomes and sex determination.
- Published
- 2020