P element homing to the Drosophila bithorax complex

Development ◽  
2000 ◽  
Vol 127 (18) ◽  
pp. 3981-3992 ◽  
Author(s):  
W. Bender ◽  
A. Hudson
Keyword(s):  
Selectable Marker ◽  
Transcription Unit ◽  
P Element ◽  
Bithorax Complex ◽  
Lacz Reporter ◽  
P Elements ◽  
Insertion Sites ◽  
Dna Fragment ◽  
Beta Galactosidase ◽  
Chromosome Regions

P elements containing a 7 kb DNA fragment from the middle of the Drosophila bithorax complex insert preferentially into the bithorax complex or into the adjacent chromosome regions. This ‘homing’ property is similar to that reported for the engrailed promoter (Hama, C., Ali, Z. and Kornberg, T. B. (1990) Genes Dev. 4, 1079–1093). The 7 kb fragment does not contain any known promoter, but it acts as a boundary element separating adjacent segmental domains. An enhancer-trap P element was constructed with the homing fragment and the selectable marker flanked by FRT sites. P insertions can be trimmed down by Flp-mediated recombination to just the lacZ reporter, so that the (beta)-galactosidase pattern is not influenced by sequences inside the P element. Twenty insertions into the bithorax complex express (beta)-galactosidase in segmentally limited patterns, reflecting the segmental domains of the bithorax complex where the elements reside. The mapping of segmental domains has now been revised, with enlargement of the abx/bx, bxd/pbx, and the iab-3 domains. The FRT sites in the P elements permit recombination between pairs of elements on opposite chromosomes, to generate duplications or deletions of the DNA between the two insertion sites. Using this technique, the length of the Ultrabithorax transcription unit was varied from 37 to 138 kb, but there was surprisingly little effect on Ultrabithorax function.

Enhancer traps in the Drosophila bithorax complex mark parasegmental domains.

Genetics ◽  
1994 ◽  
Vol 138 (2) ◽  
pp. 387-399
Author(s):  
K McCall ◽  
M B O'Connor ◽  
W Bender
Keyword(s):  
Protein Pattern ◽  
Polycomb Group ◽  
P Element ◽  
Homeotic Genes ◽  
Bithorax Complex ◽  
Lacz Expression ◽  
Regulatory Regions ◽  
P Elements ◽  
Endogenous Genes ◽  
Beta Galactosidase

Abstract Eight P elements carrying a beta-galactosidase (lacZ) reporter have been mapped to sites within the Drosophila bithorax complex. The bithorax complex contains three homeotic genes, and at least nine regulatory regions which control their expression in successive parasegments of the fly. The enhancer traps inserted at the promoter of one of the genes, Ultrabithorax, express lacZ in patterns which mimic the Ultrabithorax protein pattern. Enhancer traps in the regulatory regions do not mimic the endogenous genes, but express lacZ globally in the relevant parasegments. Some P elements carry large DNA fragments upstream of the lacZ promoter but internal to the P element. In cases where these internal sequences specify a lacZ pattern, that pattern is generally suppressed when the element is inserted in the bithorax complex. In embryos mutant for genes of the Polycomb group, the lacZ expression from the enhancer traps spreads to all segments. Thus, the enhancer traps reveal parasegmental domains that are maintained by Polycomb-mediated repression. Such domains may be realized by parasegmental differences in chromatin structure.

scholarly journals Interactions of Drosophila Ultrabithorax Regulatory Regions With Native and Foreign Promoters

Genetics ◽  
1997 ◽  
Vol 145 (1) ◽  
pp. 123-137 ◽  
Author(s):  
Fernando Casares ◽  
Welcome Bender ◽  
John Merriam ◽  
Ernesto Sánchez-Herrero
Keyword(s):  
P Element ◽  
Lacz Gene ◽  
Bithorax Complex ◽  
Lacz Reporter ◽  
Normal Pattern ◽  
Lacz Reporter Gene ◽  
Regulatory Regions ◽  
Long Range Interactions ◽  
In Trans ◽  
Dependent Interaction

The Ultrabithorax (Ubx) gene of the Drosophila bithorax complex is required to specify parasegments 5 and 6. Two P-element “enhancer traps” have been recovered within the locus that contain the bacterial lacZ gene under the control of the P-element promoter. The P insertion that is closer to the Ubx promoter expresses lucZ in a pattern similar to that of the normal Ubx gene, but also in parasegment 4 during embryonic development. Two deletions have been recovered that remove the normal Ubx promoter plus several kilobases on either side, but retain the lacZ reporter gene. The lacZ patterns from the deletion derivatives closely match the normal pattern of Ubx expression in late embryos and imaginal discs. The lacZ genes in the deletion derivatives are also negatively regulated by Ubx and activated in trans by Contrabithorax mutations, again like the normal Ubx gene. Thus, the deleted regions, including several kilobases around the Ubx promoter, are not required for long range interactions with Ubx regulatory regions. The deletion derivatives also stimulate transvection, a pairing-dependent interaction with the Ubx promoter on the homologous chromosome.

Transcription activates repressed domains in theDrosophilabithorax complex

Development ◽  
2002 ◽  
Vol 129 (21) ◽  
pp. 4923-4930 ◽  
Author(s):  
Welcome Bender ◽  
Daniel P. Fitzgerald
Keyword(s):  
Abdominal Segment ◽  
Mutant Phenotype ◽  
P Element ◽  
Bithorax Complex ◽  
Regulatory Regions ◽  
P Elements

A series of mutations have been recovered in the bithorax complex of D. melanogaster that transform the first segment of the abdomen into a copy of the second or third abdominal segment. These dominantUltraabdominal alleles are all associated with P element insertions which are transcribed in the first abdominal segment. The transcripts proceed past the end of the P element for up to 50 kb, extending through the regulatory regions for the second and third abdominal segments. Blocking transcription from the P element promoter reverts the mutant phenotype. Previously identified Ultraabdominal alleles, not associated with P elements, also show abnormal transcription of the same region.

A genetic approach to the dissection of P transposable element functions in Drosophila

1984 ◽  
Vol 307 (1132) ◽  
pp. 231-238
Keyword(s):  
Transposable Element ◽  
Selectable Marker ◽  
Marker Gene ◽  
P Element ◽  
Genetic Approach ◽  
Selectable Marker Gene ◽  
P Elements ◽  
P Transposable Element

We have made a P element derivative that carries the selectable marker gene rosy, but which acts like a non-defective, intact P element. When introduced into an M strain fly, this element continues to transpose autonomously within the genome, and elicits certain other characteristics of hybrid dysgenesis. By mutagenizing the P element in vitro , and assaying its activity in vivo , both singly and in combination with other P elements, we have tentatively identified the regions of the element encoding the transposase function. In addition, we have examined the pattern of poly(A)+ transcripts encoded by P elements of natural P strains, and by our P element marked with rosy in transformed flies, and find two species that appear to be derived from non-defective elements, one of which may be the message for transposase.

A New Genetic Locus Controlling Growth and Proliferation in Drosophila melanogaster

Genetics ◽  
2003 ◽  
Vol 164 (3) ◽  
pp. 1015-1025
Author(s):  
Sophie Raisin ◽  
Sophie Pantalacci ◽  
Jean-Philippe Breittmayer ◽  
Pierre Léopold
Keyword(s):  
Genetic Locus ◽  
Cell Number ◽  
Transcription Unit ◽  
Wing Disc ◽  
P Element ◽  
Loss Of Function ◽  
Gene Encoding ◽  
P Elements ◽  
Multicellular Organisms ◽  
Cell Growth And Proliferation

Abstract Multicellular organisms grow through both proliferation and growth of their individual cells. We have conducted a P-element-based misexpression screen for genes whose upregulation alters wing disc growth during development. One particular group of four P elements, all inserted at cytological location 61C7-8, exhibited specific overgrowth upon misexpression in proliferating imaginal tissues. Clonal analysis revealed that upon misexpression, cell number was increased but cell size was not affected, indicating that cell growth and proliferation were induced in a coordinate manner. Loss of function at the locus produced small flies with reduced cell number, consistent with the presence of a gene encoding a positive growth regulator. We characterized a new transcription unit initiating in a region adjacent to the P insertions, which generated a complex series of polyadenylated transcripts. Although these RNAs were induced in response to misexpression, none was sufficient by itself to recapitulate overgrowth when overexpressed. This suggested either that a particular combination of these transcripts was necessary or that other sequences are involved.

scholarly journals Unusual properties of regulatory DNA from the Drosophila engrailed gene: three "pairing-sensitive" sites within a 1.6-kb region.

Genetics ◽  
1994 ◽  
Vol 136 (3) ◽  
pp. 1025-1038 ◽  
Author(s):  
J A Kassis
Keyword(s):  
Marker Gene ◽  
P Element ◽  
Drosophila Genome ◽  
Trithorax Group ◽  
Eye Color ◽  
P Elements ◽  
In Trans ◽  
Insertion Sites ◽  
Regulatory Dna ◽  
In Cis

Abstract We have previously shown that a 2-kb fragment of engrailed DNA can suppress expression of a linked marker gene, white, in the P element vector CaSpeR. This suppression is dependent on the presence of two copies of engrailed DNA-containing P elements (P[en]) in proximity in the Drosophila genome (either in cis or in trans). In this study, the 2-kb fragment was dissected and found to contain three fragments of DNA which could mediate white suppression [called "pairing-sensitive sites" (PS)]. A PS site was also identified in regulatory DNA from the Drosophila escargot gene. The eye colors of six different P[en] insertions in the escargot gene suggest an interaction between P[en]-encoded and genome-encoded PS sites. I hypothesize that white gene expression from P[en] is repressed by the formation of a protein complex which is initiated at the engrailed PS sites and also requires interactions with flanking genomic DNA. Genes were sought which influence the function of PS sites. Mutations in some Polycomb and trithorax group genes were found to affect the eye color from some P[en] insertion sites. However, different mutations affected expression from different P[en] insertion sites and no one mutation was found to affect expression from all P[en] insertion sites examined. These results suggest that white expression from P[en] is not directly regulated by members of the Polycomb and trithorax group genes, but in some cases can be influenced by them. I propose that engrailed PS sites normally act to promote interactions between distantly located engrailed regulatory sites and the engrailed promoter.

Mapping of Drosophila Mutations Using Site-Specific Male Recombination

Genetics ◽  
1998 ◽  
Vol 149 (1) ◽  
pp. 157-163
Author(s):  
Bin Chen ◽  
Tehyen Chu ◽  
Emily Harms ◽  
J Peter Gergen ◽  
Sidney Strickland
Keyword(s):  
Chromosomal Region ◽  
P Element ◽  
Male Recombination ◽  
Site Specific ◽  
Site Specific Recombination ◽  
P Elements ◽  
Element Insertion ◽  
Insertion Sites ◽  
General Method

Abstract Although recombination does not usually occur in the male Drosophila germline, site-specific recombination can be induced at the ends of P elements. This finding suggested that male recombination could be used to map Drosophila mutations. In this article, we describe the general method and its application to the mapping of two EMS-induced female-sterile mutations, grauzone and cortex. Within two months, the grauzone gene was mapped relative to seven different P-element insertion sites, and cortex was mapped relative to 23 different P-elements. The results allowed us to map grauzone to a region of about 50 kb, and cortex distal to the chromosomal region 33E. These experiments demonstrate that P-element-induced site-specific male recombination is an efficient and general method to map Drosophila autosomal mutations.

scholarly journals Transposable element-induced response to artificial selection in Drosophila melanogaster: molecular analysis of selection lines.

Genetics ◽  
1990 ◽  
Vol 125 (4) ◽  
pp. 803-811 ◽  
Author(s):  
A E Shrimpton ◽  
T F Mackay ◽  
A J Brown
Keyword(s):  
Drosophila Melanogaster ◽  
Artificial Selection ◽  
Genetic Variance ◽  
Selection Response ◽  
P Element ◽  
Induced Response ◽  
Phenotypic Variance ◽  
P Elements ◽  
Insertion Sites

Abstract Artificial selection lines for abdominal bristle score of Drosophila melanogaster established from P-M hybrid dysgenic crosses showed increases in selection response, heritability and phenotypic variance compared to similar lines started from nondysgenic crosses. To determine whether this increased genetic variance could be due to enhanced transposition of P elements following the dysgenic cross, the cytological locations (sites) of P elements were determined by in situ hybridization for the whole genome of samples of 20 individuals from the parental P strain, 20 individuals from each of the eight dysgenic selection lines, and ten individuals from each of the eight nondysgenic selection lines. Variation among and within the selection lines and the parental P strain in P element insertion sites was exceptionally high. A total of 601 sites were identified, but there was no difference in total number of sites per line, mean number of sites per individual, mean copy number per individual, or site frequency between dysgenic and nondysgenic selection lines, or between lines selected for high and low bristle score. Transposition following nondysgenic crosses may explain additional observations of accelerated selection responses in nondysgenic selection lines. It was not possible to deduce which, if any, of the several hundred insertions in the dysgenic selection lines were responsible for their extreme bristle phenotypes.

scholarly journals A COMPARISON OF MUTATION RATES FOR SPECIFIC LOCI AND CHROMOSOME REGIONS IN DYSGENIC HYBRID MALES OF DROSOPHILA MELANOGASTER

Genetics ◽  
1984 ◽  
Vol 106 (1) ◽  
pp. 85-94
Author(s):  
Michael J Simmons ◽  
John D Raymond ◽  
Nancy A Johnson ◽  
Thomas M Fahey
Keyword(s):  
Drosophila Melanogaster ◽  
X Chromosome ◽  
The Other ◽  
Hybrid Dysgenesis ◽  
P Element ◽  
Mutation Rates ◽  
P Elements ◽  
White Locus ◽  
Insertion Mutations ◽  
Chromosome Regions

ABSTRACT The mutation rates of specific loci and chromosome regions were estimated for two types of dysgenic hybrid males. These came from crosses between P or Q males and M females in the P-M system of hybrid dysgenesis. The M × P hybrids were the more mutable for each of the loci and chromosome regions tested. The Beadex locus was highly mutable in these hybrids but did not mutate at all in the sample of gametes from the M × Q hybrids. The singed locus had 75% of the mutability of Beadex in the M × P hybrids; it was also mutable in the M × Q hybrids. The white locus was only slightly mutable in the M × P hybrids and not at all mutable in the M × Q hybrids. The mutations in singed and white probably arose from the insertion of P elements into these loci; the mutations at Beadex probably involved the action of a P element located near this locus on the X chromosome of the P strain that was used in the experiments. Mutations in two chromosome regions, one including the zeste-white loci and the other near the miniature locus, were much more frequent in the M × P hybrids than in the M × Q hybrids. These mutations also probably arose from P element insertions. The implication is that insertion mutations occur infrequently in the M × Q hybrids, possibly because most of the P elements they carry are defective. In M × P hybrids, there is variation among loci with respect to P elements mutagenesis, indicating that P elements possess a degree of insertional specificity.

scholarly journals P-Element Repression in Drosophila melanogaster by Variegating Clusters of P-lacZ-white Transgenes

Genetics ◽  
2001 ◽  
Vol 159 (4) ◽  
pp. 1631-1642 ◽  
Author(s):  
Stéphane Ronsseray ◽  
Antoine Boivin ◽  
Dominique Anxolabéhère
Keyword(s):  
Drosophila Melanogaster ◽  
X Chromosome ◽  
Maternal Effect ◽  
P Element ◽  
Lacz Reporter ◽  
X Ray ◽  
Subtelomeric Heterochromatin ◽  
P Elements ◽  
In Trans ◽  
Element Activity

Abstract In Drosophila, clusters of P transgenes (P-lac-w) display a variegating phenotype for the w marker. In addition, X-ray-induced rearrangements of chromosomes bearing such clusters may lead to enhancement of the variegated phenotype. Since P-lacZ transgenes in subtelomeric heterochromatin have some P-element repression abilities, we tested whether P-lac-w clusters also have the capacity to repress P-element activity in the germline. One cluster (T-1), located on a rearranged chromosome (T2;3) and derived from a line bearing a variegating tandem array of seven P-lac-w elements, partially represses the dysgenic sterility (GD sterility) induced by P elements. This cluster also strongly represses in trans the expression of P-lacZ elements in the germline. This latter suppression shows a maternal effect. Finally, the combination of variegating P-lac-w clusters and a single P-lacZ reporter inserted in subtelomeric heterochromatic sequences at the X chromosome telomere (cytological site 1A) leads to strong repression of dysgenic sterility. These results show that repression of P-induced dysgenic sterility can be elicited in the absence of P elements encoding a polypeptide repressor and that a transgene cluster can repress the expression of a single homologous transgene at a nonallelic position. Implications for models of transposable element silencing are discussed.

Sign in / Sign up

Export Citation Format

Share Document