Genetic analysis of pattern-formation in the embryo ofDrosophila melanogaster
- 1 January 1977
- journal article
- research article
- Published by Springer Science and Business Media LLC in Wilhelm Roux' Archiv für Entwicklungsmechanik der Organismen
- Vol. 183 (3), 249-268
- https://doi.org/10.1007/bf00867325
Abstract
The mutationbicaudal (Bull, 1966) causes embryos to develop a longitudinal mirror image duplication of the posteriormost abdominal segments, while head and thorax are missing. These embryos occur with varying frequencies among eggs laid by mutant females, irrespective of the paternal genotype. Recombination and deletion mapping indicate thatbicaudal (bic) is a recessive, hypomorphic, maternal-effect mutation mapping at a single locus on the second chromosome ofDrosophila melanogaster close tovg (67.0±0.1). The frequency of bicaudal embryos depends on the age of the mother, her genetic constitution and the temperature at which she is raised. Best producers are very young females hemizygous forbic (bic/Df(2)vg B ) at 28° C. Under these conditions 80% to 90% of the eggs which differentiate can show the bicaudal embryo phenotype. Upon ageing of the mother the frequency of bicaudal embryos declines rapidly, and most of the eggs develop the normal body pattern. Temperature shift experiments suggest a temperature-sensitive period at the onset of vitellogenesis. The mutation causes several types of abnormalities in the segment pattern of theDrosophila embryo, which are interpreted as various degrees of expression of the mutant character. The most frequent abnormal phenotype is the symmetrical bicaudal embryo with one to five abdominal segments duplicated. Less frequent are asymmetrical types, in which the smaller number of segments is always in the anterior reversed part. Other phenotypes are embryos with missing or rudimentary heads, and embryos with irregular gaps in the segment pattern. In bicaudal embryos, the pole cells, formed at the posterior pole of the egg prior to blastoderm formation, are not duplicated at the anterior. The significance of thebicaudal phenotypes for embryonic pattern-formation inDrosophila is discussed.Keywords
This publication has 36 references indexed in Scilit:
- Determination During Early Embryogenesis inDrosophila melanogasterAmerican Zoologist, 1977
- A morphogenetic determinant in the anterior pole of an insect egg (Smittia spec., Chironomidae, Diptera)Developmental Biology, 1977
- Centrifugation of developing oocytes leading to embryonic defectsDevelopmental Biology, 1977
- Developmental effects of exposingDrosophila embryos to ether vapourJournal of Experimental Zoology, 1977
- Clonal analysis of primordial disc cells in the early embryo of Drosophila melanogasterDevelopmental Biology, 1976
- Localized defects of blastoderm formation in maternal effect mutants of DrosophilaDevelopmental Biology, 1975
- Positional information and the spatial pattern of cellular differentiationJournal of Theoretical Biology, 1969
- The development and fine structure of centrifuged eggs of Chironomus thummiDevelopmental Biology, 1967
- Bicaudal, a genetic factor which affects the polarity of the embryo in Drosophila melanogasterJournal of Experimental Zoology, 1966
- Developmental genetic studies on oogenesis inDrosophila melanogasterJournal of Experimental Zoology, 1963