THE LOCATION OF A MUTATOR FACTOR IN A STRAIN OF DROSOPHILA MELANOGASTER BY ASSAYING MALE RECOMBINATION

ABSTRACT In a set of "mutation accumulation lines," of Drosophila melanogaster that had originated from two different wild-caught lethal-carrying second chromosomes (Yamaguchi and Mukai 1974; Mukai and Cockerham 1977; Voelkers, Schaffer and Mukai 1980) a correlation exists between high rates of reverse mutation at two visible loci and the ability to induce male recombination (Scobie and Schaffer 1982). The second and third chromosomes were extracted from the lines demonstrating these phenomena and tested for independent ability to induce male recombination. When the wild chromosome being tested was of male origin, extracted second chromosome lines were found to induce moderate to high levels of male recombination and reduced transmission frequency of the wild chromosome (the k value). The recombinants recovered in these crosses also demonstrated a high level of double-crossover recombination without the recovery of the reciprocal double-recombinant types. In addition, identifiable portions of extracted second chromosomes of male origin have been placed on very similar, marked genetic backgrounds and tested for their ability to induce male recombination. Results of this procedure have identified two regions of the second chromosome that induce male recombination and reduce k values. These results are consistent with the hypothesis that there exist two mutator factors on the second chromosome, each associated with a "mutation accumulation line" with an unstable locus.

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A MODEL OF THE NEGATIVE CORRELATION BETWEEN MALE RECOMBINATION AND TRANSMISSION FREQUENCY IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/93.2.449 ◽

1979 ◽

Vol 93 (2) ◽

pp. 449-459

Author(s):

Yuichiro Hiraizumi

Keyword(s):

Drosophila Melanogaster ◽

Excellent Agreement ◽

Negative Correlation ◽

Regression Equations ◽

Stages Of Development ◽

Male Recombination ◽

Transmission Frequency ◽

Normal Males ◽

Sperm Dysfunction

ABSTRACT A model is proposed to account for the phenomenon of negative correlation between male recombination (θ) and transmission frequency (k) in Drosophila melanogaster. The model assumes that, in some stage or stages of development, the male recombination elements cause a particular event that does not occur in normal males and that this event, in turn, induces with certain probabilities male recombination and/or sperm dysfunction. The regression equations of θ on k predicted by the model were compared with those actually observed. There was generally excellent agreement between them.

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THE RELATIONSHIPS AMONG TRANSMISSION FREQUENCY, MALE RECOMBINATION AND PROGENY PRODUCTION IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/87.1.83 ◽

1977 ◽

Vol 87 (1) ◽

pp. 83-93

Author(s):

Yuichiro Hiraizumi

Keyword(s):

Drosophila Melanogaster ◽

Natural Population ◽

South Texas ◽

Chromosome 2 ◽

Progeny Production ◽

Male Recombination ◽

Transmission Frequency ◽

Heterozygous Male

ABSTRACT The T-007 second chromosome line, which was originally isolated in 1970 from a natural population of Drosophila melanogasterat Harlingen, south Texas, has previously been shown to be associated with several unusual genetic phenomena. In the present study, two characteristics, distorted transmission frequency and male recombination, were analyzed in relation to the progeny production of T-007 heterozygous individuals. The following points were established: (1) Distorted transmission frequency in the T-007 heterozygous male was mainly due to "elimination" of T-007 chromosomes among the progeny, while no such elimination occurred for the normal partner chromosome. (2) Transmission frequency and progeny production of the T-007 heterozygous females were normal, or at least almost normal. (3) The frequency of male recombination increased with an increasing degree of distortion. This was due to an increased number of recombinants produced per male and to a decreased number of progeny receiving the T-007 chromosome.

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A MUTATOR FACTOR IN A STRAIN OF DROSOPHILA MELANOGASTER: IDENTIFIED BY USE OF MUTATION, REVERSION RATES AND MALE RECOMBINATION

Genetics ◽

10.1093/genetics/101.3-4.417 ◽

1982 ◽

Vol 101 (3-4) ◽

pp. 417-429

Author(s):

Nita N Scobie ◽

Henry E Schaffer

Keyword(s):

Drosophila Melanogaster ◽

Mutation Accumulation ◽

Female Sterility ◽

Wild Type ◽

Male Recombination ◽

Male And Female ◽

Male And Female Sterility ◽

Visible Mutation

ABSTRACT A set of 1,000 "mutation accumulation" lines of Drosophila melanogaster, which originated from two different wild-type, lethal-bearing second chromosomes (Yamaguchi and Mukai 1974; Mukai and Cockerham 1977), was examined for evidence of a mutator factor by using the occurrence of recessive visible mutations and male recombination to identify its presence. The 1,000 lines were screened at approximately generation 240 for the presence of recessive visible mutations at twelve loci, by outcrossing to a balanced multiply marked second chromosome stock (Muller's "12ple" Bowling Green). Twenty-three lines were found to carry a visible mutation at one of the loci. Seventeen of these lines carried a mutation of either the dp or the vg locus. Mutations found in three lines, two at the dp locus and one at the vg locus, demonstrated instability as revertants to the wild type and were recovered and verified in these three cases. The three revertant lines, and three lines showing no reversion, were tested for their ability to induce male recombination. Male recombination was observed in the three lines in which revertants were recovered. Male and female sterility assays indicated conclusively that these "hybrid dysgenic" characteristics could not be used to identify lines potentially carrying mutator factors, whereas the consistent ability of the lines to induce high rates of reversion and male recombination was successful in determining that the "mutation accumulation lines" do possess mutator factors.

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AN ANALYSIS OF MALE-RECOMBINATION ELEMENTS IN A NATURAL POPULATION OF DROSOPHILA MELANOGASTER IN SOUTH TEXAS

Genetics ◽

10.1093/genetics/88.1.81 ◽

1978 ◽

Vol 88 (1) ◽

pp. 81-91

Author(s):

Kathleen A Matthews ◽

Yuichiro Hiraizumi

Keyword(s):

Drosophila Melanogaster ◽

Natural Population ◽

Sex Chromosomes ◽

South Texas ◽

Male Recombination ◽

Transmission Frequency ◽

The Third ◽

Y Chromosomes

ABSTRACT Genomes from a group of Drosophila melanogmter collected from a natural population at San Benito, South Texas, in March of 1975 were analyzed for the presence of male-recombination elements. All three autosomes and both sex chromosomes were examined, with emphasis placed on the two major autosomes, the second and third chromosomes. In samples of 16 second and 16 third chromosomes, at least half, but not all, of each were found to carry male-recombination elements. It is suggested, although the data are not conclusive, that some of the fourth, X, and Y chromosomes might also be associated with male-recombination elements.—When a male-recombination element, or elements, was located in the second chromosome, relatively more male recombination was induced in the second than in the third chromosome. This situation was reversed when the element(s) was located in the third chromosome.—Distortion of transmission frequency, one of the characteristics of previously studied second chromosome lines associated with male recombination, was confirmed for these second chromosomes that carried male-recombination elements. Similar, but less pronounced, distortion was observed for the third chromosome lines that carried male-recombination elements.

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Heterochromatic Stellate Gene Cluster in Drosophila melanogaster: Structure and Molecular Evolution

Genetics ◽

10.1093/genetics/146.1.253 ◽

1997 ◽

Vol 146 (1) ◽

pp. 253-262 ◽

Cited By ~ 2

Author(s):

Alexei V Tulin ◽

Galina L Kogan ◽

Dominik Filipp ◽

Maria D Balakireva ◽

Vladimir A Gvozdev

Keyword(s):

Drosophila Melanogaster ◽

Molecular Evolution ◽

Protein Kinase Ck2 ◽

Unknown Origin ◽

Open Reading Frames ◽

Β Subunit ◽

Retrotransposon Insertion ◽

High Level ◽

Kinase Ck2 ◽

Reading Frames

The 30-kb cluster comprising close to 20 copies of tandemly repeated Stellate genes was localized in the distal heterochromatin of the X chromosome. Of 10 sequenced genes, nine contain undamaged open reading frames with extensive similarity to protein kinase CK2 β-subunit; one gene is interrupted by an insertion. The heterochromatic array of Stellate repeats is divided into three regions by a 4.5-kb DNA segment of unknown origin and a retrotransposon insertion: the A region (∼14 Stellate genes), the adjacent B region (approximately three Stellate genes), and the C region (about four Stellate genes). The sequencing of Stellate copies located along the discontinuous cluster revealed a complex pattern of diversification. The lowest level of divergence was detected in nearby Stellate repeats. The marginal copies of the A region, truncated or interrupted by an insertion, escaped homogenization and demonstrated high levels of divergence. Comparison of copies in the B and C regions, which are separated by a retrotransposon insertion, revealed a high level of diversification. These observations suggest that homogenization takes place in the Stellate cluster, but that inserted sequences may impede this process.

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Creation of EcR isoform-specific mutations in Drosophila melanogaster via local P element transposition, imprecise P element excision, and male recombination

Molecular Genetics and Genomics ◽

10.1007/s00438-004-0976-x ◽

2004 ◽

Vol 271 (3) ◽

pp. 282-290 ◽

Cited By ~ 9

Author(s):

G. E. Carney ◽

A. Robertson ◽

M. B. Davis ◽

M. Bender

Keyword(s):

Drosophila Melanogaster ◽

P Element ◽

Male Recombination

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Iron Removal from Hafnium Crystal Bar by Iodide Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.576.149 ◽

2014 ◽

Vol 576 ◽

pp. 149-153

Author(s):

Li Sen Tian ◽

Yan Xin Yin ◽

Li Jun Wang

Keyword(s):

Stainless Steel ◽

Optimal Condition ◽

Cylinder Liner ◽

Iron Removal ◽

Iron Impurity ◽

K Value ◽

Filament Temperature ◽

High Level

Crystal bar hafnium prepared by the iodide process was studied. The influences of three important factors (filament temperature, retort materials and feed types) on the removal of iron from hafnium crystal bar under iodide process were investigated. Results show that the impurity contents of iron in the hafnium crystal bar decreased with the rising K value. Both the retort materials and feed types have obvious influence on the iron impurity contents of hafnium crystal bar. It is proposed that the optimal condition was attained when hafnium turnings was used as feed, stainless steel with molybdenum cylinder liner as retort materials, and K value was at a relatively high level.

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Evidence That Runt Acts as a Counter-Repressor of Groucho During Drosophila melanogaster Primary Sex Determination

G3 Genes|Genome|Genetics ◽

10.1534/g3.120.401384 ◽

2020 ◽

Vol 10 (7) ◽

pp. 2487-2496

Author(s):

Sharvani Mahadeveraju ◽

Young-Ho Jung ◽

James W. Erickson

Keyword(s):

Drosophila Melanogaster ◽

Sex Determination ◽

Transcriptional Repression ◽

Biological Effects ◽

Regulatory Gene ◽

Animal Cells ◽

Interaction Domain ◽

Link Type ◽

High Level ◽

Runx Proteins

Runx proteins are bifunctional transcription factors that both repress and activate transcription in animal cells. Typically, Runx proteins work in concert with other transcriptional regulators, including co-activators and co-repressors to mediate their biological effects. In Drosophila melanogaster the archetypal Runx protein, Runt, functions in numerous processes including segmentation, neurogenesis and sex determination. During primary sex determination Runt acts as one of four X-linked signal element (XSE) proteins that direct female-specific activation of the establishment promoter (Pe) of the master regulatory gene Sex-lethal (Sxl). Successful activation of SxlPe requires that the XSE proteins overcome the repressive effects of maternally deposited Groucho (Gro), a potent co-repressor of the Gro/TLE family. Runx proteins, including Runt, contain a C-terminal peptide, VWRPY, known to bind to Gro/TLE proteins to mediate transcriptional repression. We show that Runt’s VWRPY co-repressor-interaction domain is needed for Runt to activate SxlPe. Deletion of the Gro-interaction domain eliminates Runt-ability to activate SxlPe, whereas replacement with a higher affinity, VWRPW, sequence promotes Runt-mediated transcription. This suggests that Runt may activate SxlPe by antagonizing Gro function, a conclusion consistent with earlier findings that Runt is needed for Sxl expression only in embryonic regions with high Gro activity. Surprisingly we found that Runt is not required for the initial activation of SxlPe. Instead, Runt is needed to keep SxlPe active during the subsequent period of high-level Sxl transcription suggesting that Runt helps amplify the difference between female and male XSE signals by counter-repressing Gro in female, but not in male, embryos.

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