Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae).
A wide variety of sex determination systems exist among squamate reptiles. They can therefore serve as an important model for studies of evolutionary transitions among particular sex determination systems. However, we still have only a limited knowledge of sex determination in certain important line...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2014-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC4131918?pdf=render |
| _version_ | 1817979932103409664 |
|---|---|
| author | Martina Johnson Pokorná Michail Rovatsos Lukáš Kratochvíl |
| author_facet | Martina Johnson Pokorná Michail Rovatsos Lukáš Kratochvíl |
| author_sort | Martina Johnson Pokorná |
| collection | DOAJ |
| description | A wide variety of sex determination systems exist among squamate reptiles. They can therefore serve as an important model for studies of evolutionary transitions among particular sex determination systems. However, we still have only a limited knowledge of sex determination in certain important lineages of squamates. In this respect, one of the most understudied groups is the family Helodermatidae (Anguimorpha) encompassing the only two venomous species of lizards which are potentially lethal to human beings. We uncovered homomorphic ZZ/ZW sex chromosomes in the Gila monster (Heloderma suspectum) with a highly heterochromatic W chromosome. The sex chromosomes are morphologically similar to the ZZ/ZW sex chromosomes of monitor lizards (Varanidae). If the sex chromosomes of helodermatids and varanids are homologous, female heterogamety may be ancestral for the whole Anguimorpha group. Moreover, we found that the karyotype of the Gila monster consists of 2n = 36 chromosomes (14 larger metacentric chromosomes and 22 acrocentric microchromosomes). 2n = 36 is the widely distributed chromosomal number among squamates. In his pioneering works representing the only previous cytogenetic examination of the family Helodermatidae, Matthey reported the karyotype as 2n = 38 and suggested a different chromosomal morphology for this species. We believe that this was probably erroneously. We also discovered a strong accumulation of telomeric sequences on several pairs of microchromosomes in the Gila monster, which is a trait documented relatively rarely in vertebrates. These new data fill an important gap in our understanding of the sex determination and karyotype evolution of squamates. |
| first_indexed | 2024-04-13T22:48:17Z |
| format | Article |
| id | doaj.art-521f1e90d6304c16a65460e0b958fee1 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-13T22:48:17Z |
| publishDate | 2014-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-521f1e90d6304c16a65460e0b958fee12022-12-22T02:26:18ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-0198e10471610.1371/journal.pone.0104716Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae).Martina Johnson PokornáMichail RovatsosLukáš KratochvílA wide variety of sex determination systems exist among squamate reptiles. They can therefore serve as an important model for studies of evolutionary transitions among particular sex determination systems. However, we still have only a limited knowledge of sex determination in certain important lineages of squamates. In this respect, one of the most understudied groups is the family Helodermatidae (Anguimorpha) encompassing the only two venomous species of lizards which are potentially lethal to human beings. We uncovered homomorphic ZZ/ZW sex chromosomes in the Gila monster (Heloderma suspectum) with a highly heterochromatic W chromosome. The sex chromosomes are morphologically similar to the ZZ/ZW sex chromosomes of monitor lizards (Varanidae). If the sex chromosomes of helodermatids and varanids are homologous, female heterogamety may be ancestral for the whole Anguimorpha group. Moreover, we found that the karyotype of the Gila monster consists of 2n = 36 chromosomes (14 larger metacentric chromosomes and 22 acrocentric microchromosomes). 2n = 36 is the widely distributed chromosomal number among squamates. In his pioneering works representing the only previous cytogenetic examination of the family Helodermatidae, Matthey reported the karyotype as 2n = 38 and suggested a different chromosomal morphology for this species. We believe that this was probably erroneously. We also discovered a strong accumulation of telomeric sequences on several pairs of microchromosomes in the Gila monster, which is a trait documented relatively rarely in vertebrates. These new data fill an important gap in our understanding of the sex determination and karyotype evolution of squamates.http://europepmc.org/articles/PMC4131918?pdf=render |
| spellingShingle | Martina Johnson Pokorná Michail Rovatsos Lukáš Kratochvíl Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae). PLoS ONE |
| title | Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae). |
| title_full | Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae). |
| title_fullStr | Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae). |
| title_full_unstemmed | Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae). |
| title_short | Sex chromosomes and karyotype of the (nearly) mythical creature, the Gila monster, Heloderma suspectum (Squamata: Helodermatidae). |
| title_sort | sex chromosomes and karyotype of the nearly mythical creature the gila monster heloderma suspectum squamata helodermatidae |
| url | http://europepmc.org/articles/PMC4131918?pdf=render |
| work_keys_str_mv | AT martinajohnsonpokorna sexchromosomesandkaryotypeofthenearlymythicalcreaturethegilamonsterhelodermasuspectumsquamatahelodermatidae AT michailrovatsos sexchromosomesandkaryotypeofthenearlymythicalcreaturethegilamonsterhelodermasuspectumsquamatahelodermatidae AT lukaskratochvil sexchromosomesandkaryotypeofthenearlymythicalcreaturethegilamonsterhelodermasuspectumsquamatahelodermatidae |