Summary
Addition of heterochromatin suppresses while subtraction enhances position effect variegation. The heterochromatin-sensitive period has been determined in white/white-apricot variegated eyes of Y S w a/w a; Dp (1;3) w 265-58 flies. When such larvae, carrying a Y-short (Y S) arm at the distal end of one X chromosome, are X-rayed, mitotic recombination leads to one daughter cell with two Y S arms and an adjacent daughter cell with no Y S arm. When induced after clonal initiation, the frequency of dark clones developing from daughter cells with two Y S arms is significantly higher than the frequency of dark clones in the rest of the eye; and this frequency is. even higher when induced before clonal initiation. The modifying action of the Y-heterochromatin is exerted, therefore, during and after clonal initiation. Surprisingly, the frequency of dark clones developing from cells with no Y S arm is not lower than the frequency of dark clones in the rest of the eye.
Similar content being viewed by others
References
Baker, W.K.: Genetic control of pigment differentiation in somatic cells. Amer. Zool. 3, 57–69 (1963)
Baker, W.K.: Position-effect variegation. Advanc. Genet. 14, 133–169 (1968)
Backer, H.J.: Über Röntgenmosaikflecken und Defektmutationen am Auge von Drosophila und die Entwicklungsphysiologie des Auges. Z. indukt. Abstamm.-u. Vererb.-L. 88, 333–373 (1957)
Becker, H.J.: Untersuchungen zur Wirkung des Heterochromatins auf die Genmanifestierung bei Drosophila melanogaster. Verh. Dtsch. Zool. Ges. Bonn/Rhein 1960, 283–291 (1961)
Chen, S.Y.: Action de la température sur troi mutants à panachure de Drosophila melanogaster: w 258-18, w m5 et z. Bull. Biol. France Belg. 82, 114–129 (1948)
Demerec, M.: Genetic behavior of euchromatic segments inserted into heterochromatin. Genetics 25, 618–627 (1940)
Gowen, J.W., Gay, E.H.: Eversporting as a function of the Y-chromosome in Drosophila melanogaster. Proc. nat. Acad. Sci. (Wash.) 19, 122–126 (1933)
Gsell, R.: Untersuchungen zur Stabilität einer yellow Positionseffekt-Variegation in Imaginalscheiben-Kulturen von Drosophila melanogaster. Molec. gen. Genet. 110, 218–237 (1971)
Janning, W.: Bestimmung des Heterochromatisierungsstadiums beim white-Positionseffekt mittels röntgeninduzierter mitotischer Rekombination in der Augenanlage von Drosophila melanogaster. Molec. gen. Genet. 107, 128–149 (1970)
Lindsley, D.L., Grell, E.H.: Genetic variations of Drosophila melanogaster. Carnegie Inst. Wash. Publ. 627 (1968)
Sutton, E.: The structure of salivary gland chromosomes of Drosophila melanogaster in exchanges between euchromatin and heterochromatin. Genetics 25, 534–540 (1940)
Author information
Authors and Affiliations
Additional information
Communicated by Ch. Auerbach
Rights and permissions
About this article
Cite this article
Becker, H.J., Janning, W. Heterochromatin of the Drosophila melanogaster Y chromosome as modifier of position effect variegation: The time of its action. Molec. gen. Genet. 151, 111–114 (1977). https://doi.org/10.1007/BF00338684
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00338684