Abstract
We describe the isolation and characterization of Aberrant X segregation (Axs), a dominant female-specific meiotic mutation. Although Axs has little or no effect on the frequency or distribution of exchange, or on the disjunction of exchange bivalents, nonexchange X chromosomes undergo nondisjunction at high frequencies in Axs/+ and Axs/Axs females. This increased X chromosome nondisjunction is shown to be a consequence of an Axs-induced defect in distributive segregation. In Axs-bearing females, fourth chromosome nondisjunction is observed only in the presence of nonexchange X chromosomes and is argued to be the result of improper X and fourth chromosome associations within the distributive system. In XX females bearing a compound fourth chromosome, the frequency of nonhomologous disjunction of the X chromosomes from the compound fourth chromosome is shown to account for at least 80% of the total X nondisjunction observed. In addition, Axs diminishes or ablates the capacity of nonexchange X chromosomes to form trivalents in females bearing either a Y chromosome or a small free duplication for the X. Axs also impairs compound X from Y segregation. The effect of Axs on these segregations parallels the defects observed for homologous nonexchange X chromosome disjunction in Axs females. In addition to its dramatic effects on the X chromosome, Axs exerts a similar effect on the segregation of a major autosome. We conclude that Axs defines a locus required for proper homolog disjunction within the distributive system.
Full Text
The Full Text of this article is available as a PDF (4.1 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Baker B. S., Carpenter A. T. Genetic analysis of sex chromosomal meiotic mutants in Drosophilia melanogaster. Genetics. 1972 Jun;71(2):255–286. doi: 10.1093/genetics/71.2.255. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Carpenter A. T. A meiotic mutant defective in distributive disjunction in Drosophila melanogaster. Genetics. 1973 Mar;73(3):393–428. doi: 10.1093/genetics/73.3.393. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooper K W. Normal Segregation without Chiasmata in Female Drosophila Melanogaster. Genetics. 1945 Sep;30(5):472–484. doi: 10.1093/genetics/30.5.472. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooper K. W. A New Theory of Secondary Non-Disjunction in Female Drosophila Melanogaster. Proc Natl Acad Sci U S A. 1948 May;34(5):179–187. doi: 10.1073/pnas.34.5.179. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cooper K. W., Zimmering S., Krivshenko J. INTERCHROMOSOMAL EFFECTS AND SEGREGATION. Proc Natl Acad Sci U S A. 1955 Nov 15;41(11):911–914. doi: 10.1073/pnas.41.11.911. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Davis D. G. Chromosome Behavior under the Influence of Claret-Nondisjunctional in DROSOPHILA MELANOGASTER. Genetics. 1969 Mar;61(3):577–594. doi: 10.1093/genetics/61.3.577. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GRELL R. F. A new model for secondary nondisjunction: the role of distributive pairing. Genetics. 1962 Dec;47:1737–1754. doi: 10.1093/genetics/47.12.1737. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GRELL R. F. DISTRIBUTIVE PAIRING: THE SIZE-DEPENDENT MECHANISM FOR REGULAR SEGREGATION OF THE FOURTH CHROMOSOMES IN DROSOPHILA MELANOGASTER. Proc Natl Acad Sci U S A. 1964 Aug;52:226–232. doi: 10.1073/pnas.52.2.226. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grell E H. Distributive Pairing of Compound Chromosomes in Females of Drosophila Melanogaster. Genetics. 1963 Sep;48(9):1217–1229. doi: 10.1093/genetics/48.9.1217. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grell R F. Non Random Assortment of Non-Homologous Chromosomes in Drosophila Melanogaster. Genetics. 1959 May;44(3):421–435. doi: 10.1093/genetics/44.3.421. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grell R. F., Grell E. H. THE BEHAVIOR OF NONHOMOLOGOUS CHROMOSOMAL ELEMENTS INVOLVED IN NONRANDOM ASSORTMENT IN DROSOPHILA MELANOGASTER. Proc Natl Acad Sci U S A. 1960 Jan;46(1):51–57. doi: 10.1073/pnas.46.1.51. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grell R. F. Pairing at the chromosomal level. J Cell Physiol. 1967 Oct;70(2 Suppl):119–146. doi: 10.1002/jcp.1040700410. [DOI] [PubMed] [Google Scholar]
- Grell R. F. The time of initiation of segregational pairing between nonhomologues in Drosophila melanogaster: a reexamination of wm4. Genetics. 1970 Feb;64(2):337–365. doi: 10.1093/genetics/64.2.337. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hall J. C. Chromosome segregation influenced by two alleles of the meiotic mutant c(3)G in Drosophila melanogaster. Genetics. 1972 Jul;71(3):367–400. doi: 10.1093/genetics/71.3.367. [DOI] [PubMed] [Google Scholar]
- Lindsley D L, Sandler L. The Meiotic Behavior of Grossly Deleted X Chromosomes in Drosophila Melanogaster. Genetics. 1958 May;43(3):547–563. doi: 10.1093/genetics/43.3.547. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MERRIAM J. R., FROST J. N. EXCHANGE AND NONDISJUNCTION OF THE X CHROMOSOMES IN FEMALE DROSOPHILA MELANOGASTER. Genetics. 1964 Jan;49:109–122. doi: 10.1093/genetics/49.1.109. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Miklos G. L., Yamamoto M. T., Davies J., Pirrotta V. Microcloning reveals a high frequency of repetitive sequences characteristic of chromosome 4 and the beta-heterochromatin of Drosophila melanogaster. Proc Natl Acad Sci U S A. 1988 Apr;85(7):2051–2055. doi: 10.1073/pnas.85.7.2051. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moore C. M., Grell R. F. Factors affecting recognition and disjunction of chromosomes at distributive pairing in female Drosophila melanogaster. I. Total length vs. arm length. Genetics. 1972 Apr;70(4):567–581. doi: 10.1093/genetics/70.4.567. [DOI] [PMC free article] [PubMed] [Google Scholar]
- O'Tousa J. Meiotic chromosome behavior influenced by mutation-altered disjunction in Drosophila melanogaster females. Genetics. 1982 Nov;102(3):503–524. doi: 10.1093/genetics/102.3.503. [DOI] [PMC free article] [PubMed] [Google Scholar]
- OKSALA T. Chromosome pairing, crossing over, and segregation in meiosis in Drosophila melanogaster females. Cold Spring Harb Symp Quant Biol. 1958;23:197–210. doi: 10.1101/sqb.1958.023.01.023. [DOI] [PubMed] [Google Scholar]
- Parry D. M. A meiotic mutant affecting recombination in female Drosophila melanogaster. Genetics. 1973 Mar;73(3):465–486. doi: 10.1093/genetics/73.3.465. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ritossa F. M. Unstable redundancy of genes for ribosomal RNA. Proc Natl Acad Sci U S A. 1968 Jun;60(2):509–516. doi: 10.1073/pnas.60.2.509. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Robbins L. G. Nonexchange alignment: a meiotic process revealed by a synthetic meiotic mutant of Drosophila melanogaster. Mol Gen Genet. 1971;110(2):144–166. doi: 10.1007/BF00332645. [DOI] [PubMed] [Google Scholar]
- STURTEVANT A. H. A map of the fourth chromosome of Drosophila melanogaster, based on crossing over in triploid females. Proc Natl Acad Sci U S A. 1951 Jul;37(7):405–407. doi: 10.1073/pnas.37.7.405. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sandler L, Novitski E. Evidence for Genetic Homology between Chromosomes I and IV in Drosophila Melanogaster, with a Proposed Explanation for the Crowding Effect in Triploids. Genetics. 1956 Mar;41(2):189–193. doi: 10.1093/genetics/41.2.189. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sturtevant A H, Beadle G W. The Relations of Inversions in the X Chromosome of Drosophila Melanogaster to Crossing over and Disjunction. Genetics. 1936 Sep;21(5):554–604. doi: 10.1093/genetics/21.5.554. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tartof K. D. Regulation of ribosomal RNA gene multiplicity in Drosophila melanogaster. Genetics. 1973 Jan;73(1):57–71. doi: 10.1093/genetics/73.1.57. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weinstein A. The Theory of Multiple-Strand Crossing over. Genetics. 1936 May;21(3):155–199. doi: 10.1093/genetics/21.3.155. [DOI] [PMC free article] [PubMed] [Google Scholar]