High resolution mapping of genetic factors affecting abdominal bristle number in Drosophila melanogaster.

Abstract Factors responsible for selection response for abdominal bristle number and correlated responses in sternopleural bristle number were mapped to the X and third chromosome of Drosophila melanogaster. Lines divergent for high and low abdominal bristle number were created by 25 generations of artificial selection from a large base population, with an intensity of 25 individuals of each sex selected from 100 individuals of each sex scored per generation. Isogenic chromosome substitution lines in which the high (H) X or third chromosome were placed in an isogenic low (L) background were derived from the selection lines and from the 93 recombinant isogenic (RI) HL X and 67 RI chromosome 3 lines constructed from them. Highly polymorphic neutral roo transposable elements were hybridized in situ to the polytene chromosomes of the RI lines to create a set of cytogenetic markers. These techniques yielded a dense map with an average spacing of 4 cM between informative markers. Factors affecting bristle number, and relative viability of the chromosome 3 RI lines, were mapped using a multiple regression interval mapping approach, conditioning on all markers > or = 10 cM from the tested interval. Two factors with large effects on abdominal bristle number were mapped on the X chromosome and five factors on the third chromosome. One factor with a large effect on sternopleural bristle number was mapped to the X and two were mapped to the third chromosome; all factors with sternopleural effects corresponded to those with effects on abdominal bristle number. Two of the chromosome 3 factors with large effects on abdominal bristle number were also associated with reduced viability. Significant sex-specific effects and epistatic interactions between mapped factors of the same order of magnitude as the additive effects were observed. All factors mapped to the approximate positions of likely candidate loci (ASC, bb, emc, h, mab, Dl and E(spl), previously characterized by mutations with large effects on bristle number.

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Genetics of Differences in Pheromonal Hydrocarbons Between Drosophila melanogaster and D. simulans

Genetics ◽

10.1093/genetics/143.1.353 ◽

1996 ◽

Vol 143 (1) ◽

pp. 353-364 ◽

Cited By ~ 3

Author(s):

Jerry A Coyne

Keyword(s):

Drosophila Melanogaster ◽

Sexual Dimorphism ◽

Genetic Analysis ◽

Species Difference ◽

The Other ◽

Chromosome 3 ◽

Apparent Effect ◽

The Third ◽

Hydrocarbon Profile ◽

The Right

Abstract Females of Drosophila melanogaster and its sibling species D. simulans have very different cuticular hydrocarbons, with the former bearing predominantly 7,11-heptacosadiene and the latter 7-tricosene. This difference contributes to reproductive isolation between the species. Genetic analysis shows that this difference maps to only the third chromosome, with the other three chromosomes having no apparent effect. The D. simulans alleles on the left arm of chromosome 3 are largely recessive, allowing us to search for the relevant regions using D. melanogaster deficiencies. At least four nonoverlapping regions of this arm have large effects on the hydrocarbon profile, implying that several genes on this arm are responsible for the species difference. Because the right arm of chromosome 3 also affects the hydrocarbon profile, a minimum of five genes appear to be involved. The large effect of the third chromosome on hydrocarbons has also been reported in the hybridization between D. simulans and its closer relative D. sechellia, implying either an evolutionaly convergence or the retention in D. sechllia of an ancestral sexual dimorphism.

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Studies on The Scutellar Bristles of Drosophila Melanogaster I. Basic Variability, Some Temperature and Culture Effects, and Responses to Short-Term Selection in the Oregon-Rc Strain

Australian Journal of Biological Sciences ◽

10.1071/bi9680721 ◽

1968 ◽

Vol 21 (4) ◽

pp. 721 ◽

Cited By ~ 6

Author(s):

BL Sheldon

Keyword(s):

Drosophila Melanogaster ◽

Major Gene ◽

Selection Response ◽

Wild Type ◽

Short Term ◽

Term Selection ◽

Bristle Number ◽

Selection For ◽

High Selection ◽

Culture Effects

The results of short runs of disruptive and high selection for scutellar bristles in wild-type Drosophila are explained in terms of the hypothesis that canalization at four bristles is due to regulation of the major gene in the developmental system (Rendel, Sheldon, and Finlay 1965). Selection response has probably been due to selection for modifier (minor) genes rather than for isoalleles of the major gene or weak regulator alleles. Some environmental effects on the character, short runs of selection for low bristle number or different bristle types, and effects of relaxing selection are also reported.

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An Analysis of Polygenes Affecting Wing Shape on Chromosome 3 in Drosophila melanogaster

Genetics ◽

10.1093/genetics/153.2.773 ◽

1999 ◽

Vol 153 (2) ◽

pp. 773-786 ◽

Cited By ~ 11

Author(s):

Kenneth Weber ◽

Robert Eisman ◽

Lisa Morey ◽

April Patty ◽

Joshua Sparks ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Transposable Elements ◽

Wing Shape ◽

The Other ◽

Chromosome 3 ◽

Additive Effects ◽

Data Set ◽

The Third ◽

Isogenic Lines ◽

Negative Interactions

AbstractLoci on the third chromosome of Drosophila melanogaster that affect an index of wing shape were mapped, using recombinant isogenic lines, with transposable elements as markers. Many genes with small subequal effects are dispersed along the whole chromosome. Their alleles act nearly additively in heterozygotes. They have small correlated effects on leg shape, but no detectable effects on halteres. Small negative net interactions occur over most of the chromosome. The data set of 519 recombinant isogenic lines can be explained reasonably well by two models. One model posits an indefinitely large number of loci with no interactions. The other model posits 11 loci with additive effects whose sum equals the total phenotypic range and with large positive and negative interactions that nearly cancel each other.

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Long-term selection for a quantitative character in large replicate populations of Drosophila melanogaster: 1. Response to selection

Genetics Research ◽

10.1017/s0016672300013896 ◽

1980 ◽

Vol 35 (1) ◽

pp. 1-17 ◽

Cited By ~ 51

Author(s):

B. H. Yoo

Keyword(s):

Drosophila Melanogaster ◽

Phenotypic Variability ◽

Selection Response ◽

Quantitative Character ◽

Response Patterns ◽

Total Response ◽

Term Selection ◽

Bristle Number ◽

Selection For

SUMMARYThe response to long-term selection for increased abdominal bristle number was studied in six replicate lines of Drosophila melanogaster derived from the sc Canberra outbred strain. Each line was continued for 86–89 generations with 50 pairs of parents selected at an intensity of 20%, and subsequently for 32–35 generations without selection. Response continued for at least 75 generations and average total response was in excess of 36 additive genetic standard deviations of the base population (σA) or 51 times the response in the first generation. The pattern of longterm response was diverse and unpredictable typically with one or more accelerated responses in later generations. At termination of the selection, most of the replicate lines were extremely unstable with high phenotypic variability, and lost much of their genetic gains rapidly upon relaxation of selection.The variation in response among replicates rose in the early phase of selection to level off at approximately 7·6 around generation 25. As some lines plateaued, it increased further to a level higher than would be accommodated by most genetic models. The replicate variation was even higher after many generations of relaxed selection. The genetic diversity among replicates, as revealed in total response, the individuality of response patterns and variation of the sex-dimorphism ratio, suggests that abdominal bristle number is influenced potentially by a large number of genes, but a smaller subset of them was responsible for selection response in any one line.

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Linkage disequilibrium mapping of molecular polymorphisms at the scabrous locus associated with naturally occurring variation in bristle number in Drosophila melanogaster

Genetics Research ◽

10.1017/s001667239900419x ◽

1999 ◽

Vol 74 (3) ◽

pp. 303-311 ◽

Cited By ~ 41

Author(s):

RICHARD F. LYMAN ◽

CHAOQIANG LAI ◽

TRUDY F. C. MACKAY

Keyword(s):

Drosophila Melanogaster ◽

Principal Component ◽

Linkage Disequilibrium Mapping ◽

The Third ◽

Naturally Occurring ◽

Single Stranded Conformational Polymorphism ◽

Bristle Number ◽

Number Variation ◽

Trait Locus ◽

Female Specific

We evaluated the hypothesis that the Drosophila melanogaster second chromosome gene scabrous (sca), a candidate sensory bristle number quantitative trait locus (QTL), contributes to naturally occurring variation in bristle number. Variation in abdominal and sternopleural bristle number was quantified for wild-derived sca alleles in seven genetic backgrounds: as homozygous second chromosomes (C2) in an isogenic background, homozygous lines in which approximately 20 cM including the sca locus had been introgressed into the isogenic background (sca BC), as C2 and sca BC heterozygotes and hemizygotes against a P element insertional sca allele and a P-induced sca deficiency in the same isogenic background, and as sca BC heterozygotes against the wild-type sca allele of isogenic strain. Molecular restriction map variation was determined for a 45 kb region including the sca locus, and single-stranded conformational polymorphism (SSCP) was examined for the third intron and parts of the third and fourth exons. Associations between each of the 27 molecular polymorphisms and bristle number were evaluated within each genotype and on the first principal component score determined from all seven genotypes, separately for each sex and bristle trait. Permutation tests were used to assess the empirical significance thresholds, accounting for multiple, correlated tests, and correlated markers. Three sites in regulatory regions were associated with female-specific variation in abdominal bristle number, one of which was an SSCP site in the region of the gene associated with regulation of sca in embryonic abdominal segments.

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Cytogenetic Analysis of the Third Chromosome Heterochromatin of Drosophila melanogaster

Genetics ◽

10.1093/genetics/160.2.509 ◽

2002 ◽

Vol 160 (2) ◽

pp. 509-517

Author(s):

Dmitry E Koryakov ◽

Igor F Zhimulev ◽

Patrizio Dimitri

Keyword(s):

Drosophila Melanogaster ◽

Mitotic Chromosome ◽

Essential Genes ◽

Chromosome 3 ◽

Cytogenetic Map ◽

Satellite Dnas ◽

Genetic Organization ◽

The Third ◽

Heterochromatic Genes ◽

Insight Into

Abstract Previous cytological analysis of heterochromatic rearrangements has yielded significant insight into the location and genetic organization of genes mapping to the heterochromatin of chromosomes X, Y, and 2 of Drosophila melanogaster. These studies have greatly facilitated our understanding of the genetic organization of heterochromatic genes. In contrast, the 12 essential genes known to exist within the mitotic heterochromatin of chromosome 3 have remained only imprecisely mapped. As a further step toward establishing a complete map of the heterochomatic genetic functions in Drosophila, we have characterized several rearrangements of chromosome 3 by using banding techniques at the level of mitotic chromosome. Most of the rearrangement breakpoints were located in the dull fluorescent regions h49, h51, and h58, suggesting that these regions correspond to heterochromatic hotspots for rearrangements. We were able to construct a detailed cytogenetic map of chromosome 3 heterochromatin that includes all of the known vital genes. At least 7 genes of the left arm (from l(3)80Fd to l(3)80Fj) map to segment h49–h51, while the most distal genes (from l(3)80Fa to l(3)80Fc) lie within the h47–h49 portion. The two right arm essential genes, l(3)81Fa and l(3)81Fb, are both located within the distal h58 segment. Intriguingly, a major part of chromosome 3 heterochromatin was found to be “empty,” in that it did not contain either known genes or known satellite DNAs.

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Sex Dimorphism and Canalization in Drosophila Melanogaster

Australian Journal of Biological Sciences ◽

10.1071/bi9691259 ◽

1969 ◽

Vol 22 (5) ◽

pp. 1259 ◽

Cited By ~ 1

Author(s):

GL Lee ◽

AS Fraser

Keyword(s):

Drosophila Melanogaster ◽

Selection Response ◽

Probit Analysis ◽

Selection Line ◽

Sex Dimorphism ◽

Slight Effect ◽

Bristle Number

Selection to reduce the sex dimorphism of scutellar bristle number associated with the gene scute in D. melanogaster was successful. Although probit analysis indicated that an increase in canalization had been achieved, the selection line was found to be still quite sensitive to temperature. The selection response was found to have no correlated effect in three other mutant genotypes nor in scute+ flies but a slight effect was noted with the gene Scutoid.

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Structure, frequency and distribution of P elements in relation to P—M hybrid dysgenic male recombination in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672300028123 ◽

1989 ◽

Vol 53 (3) ◽

pp. 163-171 ◽

Cited By ~ 1

Author(s):

K. A. Exley ◽

P. Eggleston

Keyword(s):

Drosophila Melanogaster ◽

Egg Production ◽

Polytene Chromosomes ◽

Element Distribution ◽

Hybrid Dysgenesis ◽

P Element ◽

Male Recombination ◽

P Elements ◽

Egg Hatchability ◽

The Third

SummaryThe frequency and distribution of P elements were investigated in the third chromosomes of two wild-type strains of Drosophila melanogaster using in situ hybridization of biotinylated probes to the polytene chromosomes. The relationship between these data and the extent of hybrid dysgenesis was determined through assays of egg production, egg hatchability (F2 embryo lethality), snw destabilization and male recombination along the third chromosome. The results suggest that P-element distribution, frequency and structure are all contributory factors in the regulation of hybrid dysgenesis. Texas 6 was shown consistently to be a stronger P strain than Texas 1, eliciting greater reductions in fertility, more extensive snw destabilization and higher frequencies of male recombination. Clustering of male recombination events, arising from pre-meiotic crossing over, was evident among the dysgenic progeny of each strain. Male recombination and snw destabilization were independently distributed among the dysgenic males studied, suggesting that these traits represent separate P-mediated functions. The third chromosome male recombination maps produced by the two strains differed significantly from each other and from the published female meiotic and polytene chromosome maps. Male recombination breakpoints were associated with the original distribution of P sequences in the two strains and the results suggest that this relationship may be closer for potentially complete P factors than for P sequences in general. An analysis of sub-lines derived from individual recombinant males revealed that chromosomal breakpoints could also be associated with novel insertions following P-element transposition.

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Genetic factors on the second and third chromosomes responsible for the variation of amylase activity and inducibility in Drosophila melanogaster

Genetics Research ◽

10.1017/s0016672397002887 ◽

1997 ◽

Vol 70 (2) ◽

pp. 97-103 ◽

Cited By ~ 1

Author(s):

YOSHINORI MATSUO ◽

TSUNEYUKI YAMAZAKI

Keyword(s):

Drosophila Melanogaster ◽

Genetic Factors ◽

Specific Activity ◽

Amylase Activity ◽

Chromosome Substitution ◽

Substitution Lines ◽

Functional Roles ◽

Chromosome Substitution Lines ◽

The Third ◽

Specific Activities

Using second- or third-chromosome substitution lines of Drosophila melanogaster, the genetic variation of inducibility and amylase specific activities in three media (starch, normal and glucose) were investigated. Genetic factors on both the second and third chromosomes were responsible for the variation in amylase specific activity and inducibility. In glucose medium, the genetic variance of amylase specific activity estimated for the second-chromosome substitution lines was larger than that for the third-chromosome substitution lines; however, for starch medium and inducibility, the variance was larger for the third-chromosome substitution lines. High correlations for the second-chromosome substitution lines and low correlations for the third-chromosome substitution lines were observed for amylase specific activities in different media. These results suggest that the genetic factor(s) responsible for inducibility or amylase activity variation in an induced medium such as starch should be on the third chromosome and those in the non-induced medium such as glucose should be on the second chromosome. The functional roles of the factors on the second and third chromosomes would be the repression and induction of amylase, respectively.

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Genetic analysis of the heterochromatin of chromosome 3 in Drosophila melanogaster. I. Products of compound-autosome detachment.

Genetics ◽

10.1093/genetics/120.2.503 ◽

1988 ◽

Vol 120 (2) ◽

pp. 503-517

Author(s):

G E Marchant ◽

D G Holm

Keyword(s):

Drosophila Melanogaster ◽

Genetic Analysis ◽

Genetic Characterization ◽

Complementation Analysis ◽

Chromosome 3 ◽

Recessive Lethal ◽

The Third ◽

Left And Right ◽

The Right

Abstract The heterochromatin of the third chromosome is the largest uncharacterized region of the Drosophila melanogaster genome, and the last major block of D. melanogaster heterochromatin to be thoroughly analyzed. In the present study, this region was genetically dissected by generating and analyzing a series of attached, detached and reattached third chromosomes. Separate detachment experiments were conducted for all 12 possible combinations of four newly synthesized sister-strand compound-3L and three newly synthesized sister-strand compound-3R chromosomes. A total of 443 recessive lethal detachment products carrying putative heterochromatic deficiencies were tested for complementation in a several-stage complementation analysis. The results revealed the presence of seven separable vital regions in the heterochromatin of chromosome 3. Attempts to reattach deficiency-carrying detachment products established that six of these vital regions are on the left arm, but only one is on the right arm. An analysis of the types and frequencies of detachment-product deficiencies generated in each detachment experiment permitted the genetic characterization of the progenitor compounds. It was also possible to determine the proximal-distal orientation of the genes on each arm, and to identify possible breakpoints for each lethal detachment product produced. The results of this study suggest that vital genes in the heterochromatin of the third chromosome are not randomly distributed between, nor within, the heterochromatic blocks of the left and right arms.

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