Cargando…

Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards

Parthenogenetic species of whiptail lizards in the genus Aspidoscelis constitute a striking example of speciation by hybridization, in which first-generation hybrids instantly attain reproductive isolation and procreate as clonal all-female lineages. Production of eggs containing a full complement o...

Descripción completa

Detalles Bibliográficos
Autores principales: Newton, Aracely A., Schnittker, Robert R., Yu, Zulin, Munday, Sarah S., Baumann, Diana P., Neaves, William B., Baumann, Peter
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Company of Biologists Ltd 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5201048/
https://www.ncbi.nlm.nih.gov/pubmed/27802173
http://dx.doi.org/10.1242/dev.141283
_version_ 1782489284616388608
author Newton, Aracely A.
Schnittker, Robert R.
Yu, Zulin
Munday, Sarah S.
Baumann, Diana P.
Neaves, William B.
Baumann, Peter
author_facet Newton, Aracely A.
Schnittker, Robert R.
Yu, Zulin
Munday, Sarah S.
Baumann, Diana P.
Neaves, William B.
Baumann, Peter
author_sort Newton, Aracely A.
collection PubMed
description Parthenogenetic species of whiptail lizards in the genus Aspidoscelis constitute a striking example of speciation by hybridization, in which first-generation hybrids instantly attain reproductive isolation and procreate as clonal all-female lineages. Production of eggs containing a full complement of chromosomes in the absence of fertilization involves genome duplication prior to the meiotic divisions. In these pseudo-tetraploid oocytes, pairing and recombination occur exclusively between identical chromosomes instead of homologs; a deviation from the normal meiotic program that maintains heterozygosity. Whether pseudo-tetraploid cells arise early in germ cell development or just prior to meiosis has remained unclear. We now show that in the obligate parthenogenetic species A. neomexicana the vast majority of oocytes enter meiosis as diploid cells. Telomere bouquet formation is normal, but synapsis fails and oocytes accumulate in large numbers at the pairing stage. Pseudo-tetraploid cells are exceedingly rare in early meiotic prophase, but they are the only cells that progress into diplotene. Despite the widespread failure to increase ploidy prior to entering meiosis, the fecundity of parthenogenetic A. neomexicana is similar to that of A. inornata, one of its bisexual ancestors.
format Online
Article
Text
id pubmed-5201048
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher The Company of Biologists Ltd
record_format MEDLINE/PubMed
spelling pubmed-52010482017-01-23 Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards Newton, Aracely A. Schnittker, Robert R. Yu, Zulin Munday, Sarah S. Baumann, Diana P. Neaves, William B. Baumann, Peter Development Research Article Parthenogenetic species of whiptail lizards in the genus Aspidoscelis constitute a striking example of speciation by hybridization, in which first-generation hybrids instantly attain reproductive isolation and procreate as clonal all-female lineages. Production of eggs containing a full complement of chromosomes in the absence of fertilization involves genome duplication prior to the meiotic divisions. In these pseudo-tetraploid oocytes, pairing and recombination occur exclusively between identical chromosomes instead of homologs; a deviation from the normal meiotic program that maintains heterozygosity. Whether pseudo-tetraploid cells arise early in germ cell development or just prior to meiosis has remained unclear. We now show that in the obligate parthenogenetic species A. neomexicana the vast majority of oocytes enter meiosis as diploid cells. Telomere bouquet formation is normal, but synapsis fails and oocytes accumulate in large numbers at the pairing stage. Pseudo-tetraploid cells are exceedingly rare in early meiotic prophase, but they are the only cells that progress into diplotene. Despite the widespread failure to increase ploidy prior to entering meiosis, the fecundity of parthenogenetic A. neomexicana is similar to that of A. inornata, one of its bisexual ancestors. The Company of Biologists Ltd 2016-12-01 /pmc/articles/PMC5201048/ /pubmed/27802173 http://dx.doi.org/10.1242/dev.141283 Text en © 2016. Published by The Company of Biologists Ltd http://creativecommons.org/licenses/by/3.0This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
spellingShingle Research Article
Newton, Aracely A.
Schnittker, Robert R.
Yu, Zulin
Munday, Sarah S.
Baumann, Diana P.
Neaves, William B.
Baumann, Peter
Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
title Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
title_full Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
title_fullStr Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
title_full_unstemmed Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
title_short Widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
title_sort widespread failure to complete meiosis does not impair fecundity in parthenogenetic whiptail lizards
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5201048/
https://www.ncbi.nlm.nih.gov/pubmed/27802173
http://dx.doi.org/10.1242/dev.141283
work_keys_str_mv AT newtonaracelya widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards
AT schnittkerrobertr widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards
AT yuzulin widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards
AT mundaysarahs widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards
AT baumanndianap widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards
AT neaveswilliamb widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards
AT baumannpeter widespreadfailuretocompletemeiosisdoesnotimpairfecundityinparthenogeneticwhiptaillizards