Search results for "DNA Transposable Elements"
showing 10 items of 64 documents
A single mutation alters production and discrimination of Drosophila sex pheromones
2005
0962-8452 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; The evolution of communication is a fundamental biological problem. The genetic control of the signal and its reception must be tightly coadapted, especially in inter-individual sexual communication. However, there is very little experimental evidence for tight genetic linkage connecting the emission of a signal and its reception. We found that a single genomic transposon inserted in the desatl gene of Drosophila melanogaster simultaneously affected the emission and the perception of sex-specific signals. This mutation greatly decreased the production of unsaturated hydrocarbons on the cuticle of mature fl…
Distribution of heterochromatin on the mitotic chromosomes of Musca domestica L. in relation to the activity of male-determining factors
1998
In the housefly, male sex is determined by a dominant factor, M, located either on the Y, on the X, or on any of the five autosomes. M factors on autosome I and on fragments of the Y chromosome show incomplete expressivity, whereas M factors on the other autosomes are fully expressive. To test whether these differences might be caused by heterochromatin-dependent position effects, we studied the distribution of heterochromatin on the mitotic chromosomes by C-banding and by fluorescence in situ hybridization of DNA fragments amplified from microdissected mitotic chromosomes. Our results show a correlation between the chromosomal position of M and the strength of its male-determining activity…
Transmission pattern of hobo transposable element in transgenic lines of Drosophila melanogaster
1998
This study is an attempt to trace the fate of hobo elements in the genomes of E strains of Drosophila melanogaster that have been transfected with pHFL1, a plasmid containing an autonomous hobo. Such long-term population studies (over 105 generations) could be very useful for better understanding the population and genomic dynamics of transposable elements and their pattern of insertions. Molecular analyses of hobo elements in the transfected lines were performed using Southern blots of XhoI-digested genomic DNAs. The complete element was observed in all six injected lines. In two lines we observed, at generation 100, two deleted elements, which did not correspond to Th1 and Th2. The result…
Transposition of minisatellite-like DNA in Chironomus midges.
1994
Cla elements are a family of tandem repetitive DNA sequences present in the genome of several Chironomus species. Interspersed clusters of Cla elements are widely distributed all over the chromosomes in C. thummi thummi, while they seem to be limited to the centromeric regions in the closely related subspecies C. t. piger. Here we present molecular evidence that this differential distribution is due to a transposition of Cla elements during evolution of the C. t. thummi genome. We have cloned a "filled" integration site (containing a Cla element cluster) from C. t. thummi and the corresponding "empty" genomic site from C. t. piger and other related species. The comparison shows that tandem…
Mild mutations in the pan neural gene prospero affect male-specific behaviour in Drosophila melanogaster
2004
0376-6357 (Print) Journal Article Research Support, Non-U.S. Gov't; The fruitfly Drosophila melanogaster is one of the most appropriate model organisms to study the genetics of behaviour. Here, we focus on prospero (pros), a key gene for the development of the nervous system which specifies multiple aspects from the early formation of the embryonic central nervous system to the formation of larval and adult sensory organs. We studied the effects on locomotion, courtship and mating behaviour of three mild pros mutations. These newly isolated pros mutations were induced after the incomplete excision of a transposable genomic element that, before excision, caused a lethal phenotype during larv…
Mapping of genetic loci that change pheromone discrimination in Drosophila males
2002
0016-6723 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; Reproduction in individual animals of sexual species depends largely upon their ability to detect and distinguish specific signal(s) among those produced by various potential sexual partners. In Drosophila melanogaster males, there is a natural polymorphism for discrimination of female and male principal pheromones that segregates with chromosome 3. We have mapped two loci on chromosome 3 that change sex-pheromone discrimination in males. We successively exploited meiotic recombination, deficiencies and enhancer-trap strains; excision of the transposon in two selected enhancer-trap strains clearly reverted…
Tupaia small RNAs provide insights into function and evolution of RNAi-based transposon defense in mammals
2015
Argonaute proteins comprising Piwi-like and Argonaute-like proteins and their guiding small RNAs combat mobile DNA on the transcriptional and post-transcriptional level. While Piwi-like proteins and associated piRNAs are generally restricted to the germline, Argonaute-like proteins and siRNAs have been linked with transposon control in the germline as well as in the soma. Intriguingly, evolution has realized distinct Argonaute subfunctionalization patterns in different species but our knowledge about mammalian RNA interference pathways relies mainly on findings from the mouse model. However, mice differ from other mammals by absence of functional Piwil3 and expression of an oocyte-specific …
Voila, a New Drosophila Courtship Variant that Affects the Nervous System: Behavioral, Neural, and Genetic Characterization
1998
InDrosophila melanogaster, a specificPGAL4transposon induces theVoila1genetic variant and produces multiple phenotypes. HomozygousVoila1/1flies rarely reach adulthood, whereas heterozygousVoila1/+adult males show strong bisexual behavior. Males with a single copy ofVoila1driving the feminizing transgeneUAS-transformershow very reduced sexual activity but no overall effect on their behavior.Voila1is specifically expressed in the nervous system. In the CNS, it is expressed mainly in the mushroom bodies and, to a lesser extent, in the antennal lobes. In the peripheral nervous system, GAL4 expression is almost entirely restricted to the gustatory sensilla. Using chromosomal deficiencies, the be…
Evolution-guided evaluation of the inverted terminal repeats of the synthetic transposon Sleeping Beauty.
2018
Abstract Sleeping Beauty (SB) is a synthetic Tc1/mariner transposon that is widely used for genetic engineering in vertebrates, including humans. Its sequence was derived from a consensus of sequences found in fish species including the Atlantic salmon (Salmo salar). One of the functional components of SB, the transposase enzyme, has been subject to extensive mutagenesis yielding hyperactive protein variants for advanced applications. The second functional component, the transposon inverted terminal repeats (ITRs), has so far not been extensively modified, mainly due to a lack of natural sequence information. Importantly, as genome sequences become available, they can provide a rich source …
ABO genotyping by PCR-RFLP and cloning and sequencing
2005
A refined PCR-RFLP based method was established to genotype ABO blood groups. The main objective of this study was to make the techniques also suitable for working with degraded DNA. Specific primer design was carried out to choose fragments shorter than 200 bp as necessary in forensic and archaeological applications. Four fragments of exon 6 and 7 of the ABO gene were amplified and digested by in total 7 restriction endonucleases. Particular attention was paid to the base changes at nucleotide positions 261(delG), 297, 526, 703, 721, 771, 796 and 1060(delC) in order to distinguish the six common alleles A101, A201, B, O01, O02 and O03. Furthermore, this method also enables determination of…