Top PDF Genetic and Cytological Maps of the Autosomes in Drosophila pseudoobscura

Genetic and Cytological Maps of the Autosomes in Drosophila pseudoobscura

Genetic and Cytological Maps of the Autosomes in Drosophila pseudoobscura

the cytological maps that genes Bo.re the interr~;cic:l ~:nd Since it is now lmovm in purple definitely lie within inversion,s o:f the second and third chromosomes respec- tively, arn'l [r]

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GENETIC MAPS OF THE AUTOSOMES IN DROSOPHILA PSEUDOOBSCURA

GENETIC MAPS OF THE AUTOSOMES IN DROSOPHILA PSEUDOOBSCURA

The gene bithorax was first reported by CREW and LAMY (1934b) as an autosomal recessive mutant, causing an enlargement of the balancers.. In extreme cases, the balancers may take[r]

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Mechanisms of Genetic Exchange Within the Chromosomal Inversions of Drosophila pseudoobscura

Mechanisms of Genetic Exchange Within the Chromosomal Inversions of Drosophila pseudoobscura

Coordinates of the seven loci on the different gene ar- rangement backgrounds: Because the levels and types of ge- netic exchange are sensitive to the position within an inverted region, we wished to estimate the distance between each locus and the inversion breakpoints. The complete genome of D. pseudoobscura was determined in an inbred strain that carried the Arrowhead gene arrangement (R ichards et al. 2005). This sequence was used to map the breakpoints of the Standard to Arrowhead inversion (R ichards et al. 2005). The proximal and distal Standard to Arrowhead breakpoints occur 8.9 and 14.9 Mb from the centromere, respectively. We approximated the coordinates for the pairs of breakpoints of the five other inversion events on the basis of the breakpoint locations on the cytogenetic map of Muller’s element C (see D obzhansky and S turtevant 1938, Plate I). The sections and subsections were transferred to an image of the cytogenetic map of Muller’s element C (K astritsis and C rumpacker 1966). The distance of each subsection was estimated from the photomicrograph and used to determine the proportion of each subsection relative to the total map length. The Standard to Arrowhead inversion (end of 70A to the end of 76B, Figure 1) was used as the calibration point to relate the physical and cytological map; i.e., 8.35 cm on the photomicrograph is 6.0 Mb on the physical map. This calibration was then used to predict the beginning and end points of each cytogenetic section and sub- section. The predicted subsection locations of orange (cinna- bar), engrailed, exuperantia 1, myocyte enhancing factor 2, even skipped, Amylase 1, patched, vestigial, and F6 predicted by the calibration were in good agreement with the physical map positions (T an 1937; A quadro et al. 1991; S chaeffer et al. 2003). We could now estimate the physical distance of seven genes to the inversion breakpoint of any gene arrangement by reorganizing the sec- tions and subsections on the basis of the cytological maps of the different inversions (D obzhansky 1944).
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Complex Epistasis and the Genetic Basis of Hybrid Sterility in the Drosophila pseudoobscura Bogota-USA Hybridization

Complex Epistasis and the Genetic Basis of Hybrid Sterility in the Drosophila pseudoobscura Bogota-USA Hybridization

In sum, neither the X nor the major autosomes harbor pairs, e.g., D. pseudoobscura-D. persimilis (Orr 1987) and maternal factors having a discernible effect on hybrid D. simulans-D. mauritiana (reviewed in Wu et al. 1996). male fertility. Last, we tested whether Wolbachia (or (Our finding of fertile homozygous-homozygous ex- any other tetracycline-susceptible endosymbiont) might treme genotypes is particularly unimaginable in these play a role in Bogota-USA male sterility. It does not. As other species pairs.) As emphasized in the Introduction, Table 9 shows, the cross of Bogota females ⫻ USA males the likely reason for this difference seems clear. Bogota- invariably produces sterile F 1 males, whether or not the USA is a young hybridization (Schaeffer and Miller
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EFFECTS OF TEMPERATURE ON PRODUCTIVITY AND GENETIC VARIANCE OF BODY SIZE IN POPULATIONS OF DROSOPHILA PSEUDOOBSCURA

EFFECTS OF TEMPERATURE ON PRODUCTIVITY AND GENETIC VARIANCE OF BODY SIZE IN POPULATIONS OF DROSOPHILA PSEUDOOBSCURA

Relation between parental female size and offspring size: It has been shown by various investigators that selection of parents for wing length and thorax length has a n effect o[r]

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GENETIC AND CYTOLOGICAL STUDIES ON X-RADIATION INDUCED DOMINANT EYE COLORS OF DROSOPHILA

GENETIC AND CYTOLOGICAL STUDIES ON X-RADIATION INDUCED DOMINANT EYE COLORS OF DROSOPHILA

Apparently the dominant eye-color gene is located exactly a t the point of breakage of one of the chromosomes, since the mutation never separates from the translocation [r]

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A genetic and cytological analysis of a tandem duplication and its included loci in Drosophila melanogaster

A genetic and cytological analysis of a tandem duplication and its included loci in Drosophila melanogaster

A GENETIC ABD CYTOLOGICAL ANALYSIS OF A TANDEM DUPLICATION A ND ITS INCLUDED LOOI IN DROSOPHILA MEL ANOGASTER Thesis by Edward S Lewis In Partial J'u l f11ment of the Requirements for the Degree of Do[.]

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GENETIC CONTROL OF INSECT POPULATIONS: I. CAGE STUDIES OF CHROMOSOME REPLACEMENT BY COMPOUND AUTOSOMES IN DROSOPHILA MELANOGASTER

GENETIC CONTROL OF INSECT POPULATIONS: I. CAGE STUDIES OF CHROMOSOME REPLACEMENT BY COMPOUND AUTOSOMES IN DROSOPHILA MELANOGASTER

Establishing cages in which fixed initial ratios of compounds and standards are set up (i.e., founding parents), es- sentially simulates the situation in which an insect undergoe[r]

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GENETICS OF NATURAL POPULATIONS. XI. MANIFESTATION OF GENETIC VARIANTS IN DROSOPHILA PSEUDOOBSCURA IN DIFFERENT ENVIRONMENTS

GENETICS OF NATURAL POPULATIONS. XI. MANIFESTATION OF GENETIC VARIANTS IN DROSOPHILA PSEUDOOBSCURA IN DIFFERENT ENVIRONMENTS

Viability and development rate of the homozygotes for given wild second or wild fourth chromosomes are measured by observing the segregation ratios of wild type versus B[r]

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GENETICS OF NATURAL POPULATIONS. XXIX. IS THE GENETIC LOAD IN DROSOPHILA PSEUDOOBSCURA A MUTATIONAL OR A BALANCED LOAD?

GENETICS OF NATURAL POPULATIONS. XXIX. IS THE GENETIC LOAD IN DROSOPHILA PSEUDOOBSCURA A MUTATIONAL OR A BALANCED LOAD?

The two variables are the percentage of +/+ flies in test cultures heterozygous for two different wild chromosomes, and the mean of the percentages of such flies in [r]

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GENETICS OF NATURAL POPULATIONS. XXXVI. EPISTATIC INTERACTIONS OF THE COMPONENTS OF THE GENETIC LOAD IN DROSOPHILA PSEUDOOBSCURA

GENETICS OF NATURAL POPULATIONS. XXXVI. EPISTATIC INTERACTIONS OF THE COMPONENTS OF THE GENETIC LOAD IN DROSOPHILA PSEUDOOBSCURA

A still different question that can be asked is whether the positive synergism is more likely to arise with chromosomes which lower the viability only slightly when homozygous, [r]

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GENOTYPIC BACKGROUND AND HETEROSIS IN DROSOPHILA PSEUDOOBSCURA

GENOTYPIC BACKGROUND AND HETEROSIS IN DROSOPHILA PSEUDOOBSCURA

The parents of the experimental populations reported in this section were F1 hybrids between strains in which the third chromosomes with CH gene arrangements of Mexican ori[r]

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CONCURRENT INBREEDING AND SELECTION IN DROSOPHILA PSEUDOOBSCURA

CONCURRENT INBREEDING AND SELECTION IN DROSOPHILA PSEUDOOBSCURA

The results of the F, analysis, then, indicate that selection should be effective in increasing body weight (due to additive genetic variance) and that inbreeding depression shoul[r]

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SELECTION FOR DEVELOPMENTAL RATE IN DROSOPHILA PSEUDOOBSCURA

SELECTION FOR DEVELOPMENTAL RATE IN DROSOPHILA PSEUDOOBSCURA

Five among the lines selected for rapid development had regression coefficients significantly different from zero, although a statistical test showed no significant heterogeneity a[r]

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Reproductive Biology and Speciation in Drosophila pseudoobscura

Reproductive Biology and Speciation in Drosophila pseudoobscura

this seems unlikely (17, 22, 33). Secondly, this could represent an actual strategy employed by males developed in competition to increase their share of paternity in the presence of sperm competition. There is now substantial evidence that, in polyandrous Drosophila, males that are the first to mate with a female have a far smaller share of paternity than those that are the second male to mate with the female (57). As such, males expecting competition would benefit from delaying mating until a competing male has already mated. A third possibility is that males developed in competition become choosy about the females with whom they mate. As such, when they are placed with a single female in a no-choice mating assay, they could be reluctant to mate. Lastly, it is possible that this reduction is merely a bi-product of reduced vigor induced by the presence of rival compounds or the interactions with other males. Although the adaptive nature of this last possibility is still debated, there is a large body of evidence that males who are developed in competition show less male-male aggression, as well as reduced male-male courtship(58). It is possible that the neural network responsible for reduced aggression and homosexual behaviour is also involved in male courtship vigour. It would be of interest to explore whether these networks are shared by exploring the male-male aggression behaviour in isolated males and competitively housed males.
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Genetic Characterization of Cytological Region 77A–D Harboring the Presenilin Gene of Drosophila melanogaster

Genetic Characterization of Cytological Region 77A–D Harboring the Presenilin Gene of Drosophila melanogaster

location 77B/C (Boulianne et al. 1997; Hong and Koo a semilethal mutation of the l(3)77CDj locus displays loss 1997; Ye and Fortini 1998). This region of the Drosoph- of thoracic microchaetae and a rough eye phenotype ila genome has not been subjected to systematic muta- reminiscent of the furrow-stop class of eye development tional analysis. Only a few genes in the area have been mutants, such as hedgehog, Bar, and Drop (Heberlein extensively studied, most notably polo, which encodes a et al. 1993). Our recovery of these mutations and the protein kinase needed for mitosis and meiosis (Lla- preliminary mapping data we present here should facili- mazares et al. 1991), inturned, encoding a novel trans- tate the further molecular characterization of these loci. membrane protein required for tissue polarity (Park et Genetic analysis of the genomic region immediately al. 1996), and retinal degeneration C (rdgC), encoding a surrounding the Psn transcription unit was accom- serine/threonine protein phosphatase functioning in plished by rescue experiments using several partially the visual system (Steele et al. 1992). Because our at- overlapping genomic DNA fragments. These studies led tempts to find Psn mutants among the few extant mu- to our previous identification of one lethal complemen- tants mapping to the 77B/C region were unsuccessful, tation group as Psn gene mutations (Ye et al. 1999), and we elected to perform a systematic lethal mutagenesis in this article we identify two additional essential genes of the 77A–D region uncovered by Df(3L)rdgC-co2 to located in the same z12-kb genomic DNA region as the isolate lethal Psn mutants. Our mutant alleles of Psn have Psn gene. Psn is a compact gene residing in a 3.8-kb been useful in studies of the role of Psn in proteolytic genomic DNA fragment that is capable of providing full processing of the Notch receptor (Ye et al. 1999), but Psn gene function. This DNA segment contains z1.2 we also wished to genetically characterize the 77A–D kb of 59 flanking DNA, the z2.5-kb Psn transcribed region further, given the paucity of information about region, and z100 bp of 39 flanking DNA (Ye et al. 1999). this region and the potential value of such data for the An essential gene corresponding to l(3)77CDa is located Drosophila genome project (Miklos and Rubin 1996; z4 kb upstream of Psn, and an essential gene corre- Rubin 1998). Using a standard F 2 recessive lethal screen- sponding to l(3)77CDc, encoding a fly protein with some
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HETEROCHROMATIC POSITION EFFECT AT THE ROSY LOCUS OF DROSOPHILA MELANOGASTER: CYTOLOGICAL, GENETIC AND BIOCHEMICAL CHARACTERIZATION

HETEROCHROMATIC POSITION EFFECT AT THE ROSY LOCUS OF DROSOPHILA MELANOGASTER: CYTOLOGICAL, GENETIC AND BIOCHEMICAL CHARACTERIZATION

Taken together, the cytological observations and the phenotypic effects upon rosy locus expression provide strong support for the notion that the mutational lesion associated with [r]

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GENETICS OF SEXUAL ISOLATION BETWEEN DROSOPHILA PSEUDOOBSCURA AND DROSOPHILA PERSIMILIS

GENETICS OF SEXUAL ISOLATION BETWEEN DROSOPHILA PSEUDOOBSCURA AND DROSOPHILA PERSIMILIS

Number of females dissected (hi) and percentage carrying sperm (%) in crosses between backcross hybrid females, D. pseudo- persimilis, CHROMOSOMES HYBRID ALIEN SP. pseud[r]

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POPULATION GENETICS OF DROSOPHILA AMYLASE. I. GENETIC CONTROL OF TISSUE-SPECIFIC EXPRESSION IN D. PSEUDOOBSCURA

POPULATION GENETICS OF DROSOPHILA AMYLASE. I. GENETIC CONTROL OF TISSUE-SPECIFIC EXPRESSION IN D. PSEUDOOBSCURA

cause of the possibility that a high concentration of starch (such as in standard medium) may inadvertently select against flies with limited amylase activity, we also car[r]

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GENETICS OF NATURAL POPULATIONS. XXVIII. THE MAGNITUDE OF THE GENETIC LOAD IN POPULATIONS OF DROSOPHILA PSEUDOOBSCURA

GENETICS OF NATURAL POPULATIONS. XXVIII. THE MAGNITUDE OF THE GENETIC LOAD IN POPULATIONS OF DROSOPHILA PSEUDOOBSCURA

Viability of the homozygotes: The frequencies of the +/+ flies in the cultures in which this class of flies was homozygous for different wild chromosomes are summarized in [r]

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