Comparative Cytology of Female Meiosis I Among Drosophila Species
The physical connections established by recombination are normally sufficient to ensure proper chromosome segregation during female Meiosis I. However, nonexchange chromosomes (such as the Muller F element or “dot” chromosome in D. melanogaster) can still segregate accurately because they remain con...
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| Format: | Article |
| Language: | English |
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Oxford University Press
2020-05-01
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| Series: | G3: Genes, Genomes, Genetics |
| Subjects: | |
| Online Access: | http://g3journal.org/lookup/doi/10.1534/g3.120.400867 |
| _version_ | 1818433117932748800 |
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| author | Ahmed Majekodunmi Amelia O. Bowen William D. Gilliland |
| author_facet | Ahmed Majekodunmi Amelia O. Bowen William D. Gilliland |
| author_sort | Ahmed Majekodunmi |
| collection | DOAJ |
| description | The physical connections established by recombination are normally sufficient to ensure proper chromosome segregation during female Meiosis I. However, nonexchange chromosomes (such as the Muller F element or “dot” chromosome in D. melanogaster) can still segregate accurately because they remain connected by heterochromatic tethers. A recent study examined female meiosis in the closely related species D. melanogaster and D. simulans, and found a nearly twofold difference in the mean distance the obligately nonexchange dot chromosomes were separated during Prometaphase. That study proposed two speculative hypotheses for this difference, the first being the amount of heterochromatin in each species, and the second being the species’ differing tolerance for common inversions in natural populations. We tested these hypotheses by examining female meiosis in 12 additional Drosophila species. While neither hypothesis had significant support, we did see 10-fold variation in dot chromosome sizes, and fivefold variation in the frequency of chromosomes out on the spindle, which were both significantly correlated with chromosome separation distances. In addition to demonstrating that heterochromatin abundance changes chromosome behavior, this implies that the duration of Prometaphase chromosome movements must be proportional to the size of the F element in these species. Additionally, we examined D. willistoni, a species that lacks a free dot chromosome. We observed that chromosomes still moved out on the meiotic spindle, and the F element was always positioned closest to the spindle poles. This result is consistent with models where one role of the dot chromosomes is to help organize the meiotic spindle. |
| first_indexed | 2024-12-14T16:16:00Z |
| format | Article |
| id | doaj.art-6339276d20f747588d91e3de9063e6ba |
| institution | Directory Open Access Journal |
| issn | 2160-1836 |
| language | English |
| last_indexed | 2024-12-14T16:16:00Z |
| publishDate | 2020-05-01 |
| publisher | Oxford University Press |
| record_format | Article |
| series | G3: Genes, Genomes, Genetics |
| spelling | doaj.art-6339276d20f747588d91e3de9063e6ba2022-12-21T22:54:54ZengOxford University PressG3: Genes, Genomes, Genetics2160-18362020-05-011051765177410.1534/g3.120.40086730Comparative Cytology of Female Meiosis I Among Drosophila SpeciesAhmed MajekodunmiAmelia O. BowenWilliam D. GillilandThe physical connections established by recombination are normally sufficient to ensure proper chromosome segregation during female Meiosis I. However, nonexchange chromosomes (such as the Muller F element or “dot” chromosome in D. melanogaster) can still segregate accurately because they remain connected by heterochromatic tethers. A recent study examined female meiosis in the closely related species D. melanogaster and D. simulans, and found a nearly twofold difference in the mean distance the obligately nonexchange dot chromosomes were separated during Prometaphase. That study proposed two speculative hypotheses for this difference, the first being the amount of heterochromatin in each species, and the second being the species’ differing tolerance for common inversions in natural populations. We tested these hypotheses by examining female meiosis in 12 additional Drosophila species. While neither hypothesis had significant support, we did see 10-fold variation in dot chromosome sizes, and fivefold variation in the frequency of chromosomes out on the spindle, which were both significantly correlated with chromosome separation distances. In addition to demonstrating that heterochromatin abundance changes chromosome behavior, this implies that the duration of Prometaphase chromosome movements must be proportional to the size of the F element in these species. Additionally, we examined D. willistoni, a species that lacks a free dot chromosome. We observed that chromosomes still moved out on the meiotic spindle, and the F element was always positioned closest to the spindle poles. This result is consistent with models where one role of the dot chromosomes is to help organize the meiotic spindle.http://g3journal.org/lookup/doi/10.1534/g3.120.400867chromosomesmeiosisdrosophilaheterochromatincomparative biology |
| spellingShingle | Ahmed Majekodunmi Amelia O. Bowen William D. Gilliland Comparative Cytology of Female Meiosis I Among Drosophila Species G3: Genes, Genomes, Genetics chromosomes meiosis drosophila heterochromatin comparative biology |
| title | Comparative Cytology of Female Meiosis I Among Drosophila Species |
| title_full | Comparative Cytology of Female Meiosis I Among Drosophila Species |
| title_fullStr | Comparative Cytology of Female Meiosis I Among Drosophila Species |
| title_full_unstemmed | Comparative Cytology of Female Meiosis I Among Drosophila Species |
| title_short | Comparative Cytology of Female Meiosis I Among Drosophila Species |
| title_sort | comparative cytology of female meiosis i among drosophila species |
| topic | chromosomes meiosis drosophila heterochromatin comparative biology |
| url | http://g3journal.org/lookup/doi/10.1534/g3.120.400867 |
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