Genetic control of tryptophan pyrrolase in Drosophila melanogaster and D. virilis

Baglioni, Corrado

doi:10.1038/hdy.1960.60

Cited by 50 publications

(17 citation statements)

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“…The response of v mutants to su(s) has been investigated in various genetic combinations of v and su(s) alleles by analysis of phenotypes (5-7), measurements of tryptophan oxygenase activity (2,3,(7)(8)(9), and measurements ofkynurenine autofluorescence in the larval fat body (10,11). While the function of the su(s) locus remains unknown, these studies have demonstrated that a suppressible v mutation (vI) results in a mutant phenotype only when the su(s) locus is expressed normally, i.e., in su(s)+ vs flies.…”

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confidence: 99%

Molecular characterization of the Drosophila vermilion locus and its suppressible alleles.

Searles

Voelker

1986

Proc. Natl. Acad. Sci. U.S.A.

101

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We have cloned vermilion (v), one of the genes required for brown eye pigment synthesis in Drosophila, using a mutant (vH2a) "tagged" with the transposon P factor.Mutations that disrupt v gene expression are clustered within approximately 2 kilobases of DNA. A 1.4-kilobase transcript, homologous to this same region, is present in v+ RNA but absent in RNA from several v mutants. The spontaneous v alleles that are suppressed by the suppressor of sable [su(s) MATERIALS AND METHODSPurification of Nucleic Acids. The v mutants used for nucleic acid isolation are described by Lindsley and Grell (16) or are referenced in the text. Drosophila DNA was isolated from adult flies as described by Bingham et al. (18). Procedures for isolation ofbacteriophage X DNA and plasmid DNA have been described (19). Total RNA was prepared from 2-day-old adults by using procedures described by Thireos et al. (20) except that 10 mM vanadyl-ribonucleoside complex was included in the homogenization buffer. Poly(A)+ RNA was purified by chromatography on oligo(dT)-cellulose (21 nitrocellulose (26). The hybridization conditions were the same as described for Southern transfers. The hybridization probes were plasmid subclones that had been labeled with 32P by nick-translation (27).Abbreviations: kb, kilobase(s); bp, base pair(s). 404The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

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confidence: 99%

Molecular characterization of the Drosophila vermilion locus and its suppressible alleles.

Searles

Voelker

1986

Proc. Natl. Acad. Sci. U.S.A.

101

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“…All v mutants lack tryptophane pyrrolase activity, and some respond to su(s) mutants by a partial restoration of this enzymatic activity (5). This suggests that su(s) is partially homologous to v. On the other hand, su(s) mutants also suppress mutants at loci other than v (s, 1-43.0; pr, 2-54.5; sp, 2-107.0, ref.…”

Section: Discussion and Summarymentioning

confidence: 99%

DNA-Induced Transformation in Drosophila: Genetic Analysis of Transformed Stocks

Fox

Yoon

Gelbart

1971

Proc. Natl. Acad. Sci. U.S.A.

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The exosome model of transformation in Drosophila melanogaster proposes that DNA fragments enter the cells of treated individuals and become firmly associated with their homologous chromosome segments, but are never integrated into the linear structure of the chromosome. This paper reports results that validate two central predictions of the model: (a) the introduced genetic information usually maps precisely at the site of the target locus, and (b) the original chromosomal information is still present at that site.In the first two papers of this series (la, lb) we reported data showing that the specific genetic effects of DNA in Drosophila melanogaster could properly be regarded as true genetic transformations. We suggested that the results were explicable in terms of a model in which the genetic information responsible for transformation persists in the form of exosomes; i.e., replicating DNA fragments that are closely associated with their homologous chromosome segments, but are never integrated into the linear structure of the chromosome. The principal evidence which suggested this model was the observation that transformed individuals possessing the introduced information in all of their cells were always phenotypic mosaics, and that whole-body transformants were not obtained even under experimental conditions favorable for exchange between introduced DNA and the chromosome. Unless ad hoc assumptions are made, models that postulate integration predict that whole-body transformants should be recoverable (2).We present here the genetic analysis of three transformed stocks. The results reported validate two central predictions of the exosome model: (a) the introduced genetic information usually maps precisely at the site of the target locus, and (b) the original chromosomal information is still present at that site. The one case in which the alteration maps at a site other than that of the target locus may represent either a suppressor mutant with an origin unrelated to DNA treatment, or the association of the introduced information with a region of partial homology. MATERIALS AND METHODSThree transformed stocks were utilized in this work: 6203 c!4, 8540 10, and e5-6. Their derivation and phenotypic characteristics are described in our previous communication (la

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“…With su(s) 2 and su(s) + in homozygous and heterozygous combinations the suppression of v was judged to be recessive on the basis of the visible phenotype (Bonnier, 1925;Schultz & Bridges, 1932;Marzluff, 1965;Tartof, 1969;Baillie & Chovnick, 1971). However, Baglioni (1960) observed that the eye colour of v; bw that was heterozygous for su(s) 2 had visually detectable amounts of brown eye pigment and therefore concluded that 'su(s) 2 was not recessive'. Furthermore, when Shapard (1960) measured the amount of non-protein tryptophan in adult flies, she observed a significant decrease in su(s) 2 / + compared with homozygous su(s) 2 and concluded that 'su(s) + was incompletely dominant'.…”

Section: Introductionmentioning

confidence: 92%

“…The response of pr to various alleles of su(s) was measured in terms of the drosopterin eye pigments that could be extracted and of the measurable activity of sepiapterin synthase, the enzyme for which pr is probably the structural locus (Yim, Grell & Jacobson, 1977). The response of v was measured in terms of the xanthommatin eye pigment that could be extracted and of the measurable activity of tryptophan oxygenase, the enzyme for which v is probably the structural locus (Baglioni, 1960;Baillie & Chovnick, 1971).…”

Section: Introductionmentioning

confidence: 99%

Mechanism of suppression inDrosophila melanogasterVIII. Comparison ofsu(s) alleles for ability to suppress the mutants purple, vermilion, and speck

Jacobson¹,

Grell²,

Yim³

et al. 1982

Genet. Res.

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The suppressor of sable [sw(s) 2 ] restores the function of vermilion (i>), purple (pr) and speck (sp) as well as sable (s) in Drosophila melanogaster.In this report various alleles of su(s) are compared for their relative effectiveness on three target mutations, v, pr and sp. Three criteria for suppression of pr and v were employed: visible phenotype, eye pigment levels (drosopterins and xanthommatin) and enzyme levels (sepiapterin synthase and tryptophan oxygenase). For sp only the visible phenotype was examined. By all three criteria pr was found to be more easily suppressed than v; v and sp were comparable. By use of pr with various alleles of su(s) either homozygously or in heterozygous combination with su(s) + , the extent of suppression of pr can be best demonstrated by observing the levels of sepiapterin synthase; normal levels of drosopterins were found in females when sepiapterin synthase was only 20 % of normal. On the other hand, the extent of suppression of v is best demonstrated by the amount of xanthommatin eye pigment, because even the suppressed vermilion fly has < 10% of wild-type activity of tryptophan oxygenase when 1-day-old flies are examined; in older flies this enzyme can be as high as 50 % of wild type. From these results we also demonstrated that su(s) 2 , and other alleles, are not recessive but, in heterozygous combination with su(s) + , cause marked suppression oipr and slight, but reproducible,

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Genetic control of tryptophan pyrrolase in Drosophila melanogaster and D. virilis

Cited by 50 publications

References 23 publications

Molecular characterization of the Drosophila vermilion locus and its suppressible alleles.

Molecular characterization of the Drosophila vermilion locus and its suppressible alleles.

DNA-Induced Transformation in Drosophila: Genetic Analysis of Transformed Stocks

Mechanism of suppression inDrosophila melanogasterVIII. Comparison ofsu(s) alleles for ability to suppress the mutants purple, vermilion, and speck

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