Isolating Chromosomes of the Komodo Dragon: New Tools for Comparative Mapping and Sequence Assembly

Iannucci, Alessio; Altmanová, Marie; Ciofi, Claudio; Ferguson‐Smith, Malcolm A.; Pereira, Jorge C.; Rehák, Ivan; Stanyon, Roscoe; Velenský, Petr; Rovatsos, Michail; Kratochvíl, Lukáš; Pokorná, Martina

doi:10.1159/000496171

Cited by 11 publications

(19 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A third individual from Gran Canaria was used for PacBio DNA sequencing. The Komodo dragon genome is distributed across 20 pairs of chromosomes, comprising eight pairs of large chromosomes and 12 pairs of microchromosomes 9 , 10 . De novo assembly was performed with a combination of 10x Genomics linked-read sequencing, Bionano optical mapping data, PacBio sequencing, and Oxford Nanopore MinIon sequencing (see Methods ).…”

Section: Resultsmentioning

confidence: 99%

Genome of the Komodo dragon reveals adaptations in the cardiovascular and chemosensory systems of monitor lizards

et al. 2019

Self Cite

View full text Add to dashboard Cite

Monitor lizards are unique among ectothermic reptiles in that they have high aerobic capacity and distinctive cardiovascular physiology resembling that of endothermic mammals. Here, we sequence the genome of the Komodo dragon Varanus komodoensis, the largest extant monitor lizard, and generate a high-resolution de novo chromosome-assigned genome assembly for V. komodoensis using a hybrid approach of long-range sequencing and single-molecule optical mapping. Comparing the genome of V. komodoensis with those of related species, we find evidence of positive selection in pathways related to energy metabolism, cardiovascular homoeostasis, and haemostasis. We also show species-specific expansions of a chemoreceptor gene family related to pheromone and kairomone sensing in V. komodoensis and other lizard lineages. Together, these evolutionary signatures of adaptation reveal the genetic underpinnings of the unique Komodo dragon sensory and cardiovascular systems, and suggest that selective pressure altered haemostasis genes to help Komodo dragons evade the anticoagulant effects of their own saliva. The Komodo dragon genome is an important resource for understanding the biology of monitor lizards and reptiles worldwide.

show abstract

Section: Resultsmentioning

confidence: 99%

Genome of the Komodo dragon reveals adaptations in the cardiovascular and chemosensory systems of monitor lizards

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…Varanids, including Komodo dragons, possess genotypic sex determination and share ZZ/ZW sex chromosomes with other anguimorphan lizards 14,18 . Here, we were able to detail the content of Z chromosome of V. komodoensis .…”

Section: Resultsmentioning

confidence: 99%

“…We obtained DNA from peripheral blood of two male individuals housed at Zoo Atlanta: Slasher, a male offspring of the first Komodo dragons given as gifts in 1986 to US President Reagan from President Suharto of Indonesia, and Rinca, a juvenile male (Figure 1A). The V. komodoensis genome is distributed across 20 pairs of chromosomes, comprising eight pairs of large chromosomes and 12 pairs of microchromosomes 13,14 . De novo assembly was performed using 57X coverage of 10x Genomics linked-read sequencing data to generate an initial assembly with a scaffold N50 of 10.2 Mb and a contig N50 of 95 kb.…”

Section: Resultsmentioning

confidence: 99%

“…We isolated chromosome-specific DNA pools from a female embryo of V. komodoensis (VKO) from Prague zoo stock through flow sorting 14 . We obtained Illumina short-read sequences of these 15 DNA pools containing all chromosomes of V. komodoensis (Table S3).…”

Section: Resultsmentioning

confidence: 99%

“…Isolation of V. komodoensis (VKO) chromosome-specific DNA pools as previously described 14 . Briefly, fibroblast cultivation of a female V. komodoensis were obtained from tissue samples of an early embryo of a captive individual.…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

A high-resolution, chromosome-assigned Komodo dragon genome reveals adaptations in the cardiovascular, muscular, and chemosensory systems of monitor lizards

Mostovoy

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

35Monitor lizards are unique among ectothermic reptiles in that they have a high aerobic capacity 36 and distinctive cardiovascular physiology which resembles that of endothermic mammals. We 37 have sequenced the genome of the Komodo dragon (Varanus komodoensis), the largest extant 38 monitor lizard, and present a high resolution de novo chromosome-assigned genome assembly 39 for V. komodoensis, generated with a hybrid approach of long-range sequencing and single 40 molecule physical mapping. Comparing the genome of V. komodoensis with those of related 41 species showed evidence of positive selection in pathways related to muscle energy 42 metabolism, cardiovascular homeostasis, and thrombosis. We also found species-specific 43 expansions of a chemoreceptor gene family related to pheromone and kairomone sensing in V. 44 komodoensis and several other lizard lineages. Together, these evolutionary signatures of 45 adaptation reveal genetic underpinnings of the unique Komodo sensory, cardiovascular, and 46

show abstract

Widespread chromosomal rearrangements preceded genetic divergence in a monitor lizard, Varanus acanthurus (Varanidae)

et al. 2023

View full text Add to dashboard Cite

Chromosomal rearrangements are often associated with local adaptation and speciation because they suppress recombination, and as a result, rearrangements have been implicated in disrupting gene flow. Although there is strong evidence to suggest that chromosome rearrangements are a factor in genetic isolation of divergent populations, the underlying mechanism remains elusive. Here, we applied an integrative cytogenetics and genomics approach testing whether chromosomal rearrangements are the initial process, or a consequence, of population divergence in the dwarf goanna, Varanus acanthurus. Specifically, we tested whether chromosome rearrangements are indicators of genetic barriers that can be used to identify divergent populations by looking at gene flow within and between populations with rearrangements. We found that gene flow was present between individuals with chromosome rearrangements within populations, but there was no gene flow between populations that had similar chromosome rearrangements. Moreover, we identified a correlation between reduced genetic variation in populations with a higher frequency of homozygous submetacentric individuals. These findings suggest that chromosomal rearrangements were widespread prior to divergence, and because we found populations with higher frequencies of submetacentric chromosomes were associated with lower genetic diversity, this could indicate that polymorphisms within populations are early indicators of genetic drift.

show abstract

Isolating Chromosomes of the Komodo Dragon: New Tools for Comparative Mapping and Sequence Assembly

Cited by 11 publications

References 69 publications

Genome of the Komodo dragon reveals adaptations in the cardiovascular and chemosensory systems of monitor lizards

Genome of the Komodo dragon reveals adaptations in the cardiovascular and chemosensory systems of monitor lizards

A high-resolution, chromosome-assigned Komodo dragon genome reveals adaptations in the cardiovascular, muscular, and chemosensory systems of monitor lizards

Widespread chromosomal rearrangements preceded genetic divergence in a monitor lizard, Varanus acanthurus (Varanidae)

Contact Info

Product

Resources

About