Whole-Genome Effects of Ethyl Methanesulfonate-Induced Mutation on Nine Quantitative Traits in Outbred Drosophila melanogaster

Genetics ◽  
2001 ◽  
Vol 157 (3) ◽  
pp. 1257-1265 ◽  
Author(s):  
Hsiao-Pei Yang ◽  
Ana Y Tanikawa ◽  
Wayne A Van Voorhies ◽  
Joana C Silva ◽  
Alexey S Kondrashov
Keyword(s):  
Drosophila Melanogaster ◽  
Quantitative Traits ◽  
Spontaneous Mutation ◽  
Developmental Time ◽  
Ethyl Methanesulfonate ◽  
Induced Mutations ◽  
Mean Values ◽  
Eye Color ◽  
Recessive Mutations ◽  
The Mean

Abstract We induced mutations in Drosophila melanogaster males by treating them with 21.2 mm ethyl methanesulfonate (EMS). Nine quantitative traits (developmental time, viability, fecundity, longevity, metabolic rate, motility, body weight, and abdominal and sternopleural bristle numbers) were measured in outbred heterozygous F3 (viability) or F2 (all other traits) offspring from the treated males. The mean values of the first four traits, which are all directly related to the life history, were substantially affected by EMS mutagenesis: the developmental time increased while viability, fecundity, and longevity declined. In contrast, the mean values of the other five traits were not significantly affected. Rates of recessive X-linked lethals and of recessive mutations at several loci affecting eye color imply that our EMS treatment was equivalent to ∼100 generations of spontaneous mutation. If so, our data imply that one generation of spontaneous mutation increases the developmental time by 0.09% at 20° and by 0.04% at 25°, and reduces viability under harsh conditions, fecundity, and longevity by 1.35, 0.21, and 0.08%, respectively. Comparison of flies with none, one, and two grandfathers (or greatgrandfathers, in the case of viability) treated with EMS did not reveal any significant epistasis among the induced mutations.

scholarly journals The Heritability of Some Qualitative and Quantitative Traits at One Set of Spring Barley Genotypes

2018 ◽  
Vol 75 (2) ◽  
pp. 93-100
Author(s):  
Ioana PORUMB ◽  
Florin RUSSU ◽  
Ioan ROTAR
Keyword(s):  
Quantitative Traits ◽  
Starch Content ◽  
Spring Barley ◽  
Mean Values ◽  
Qualitative And Quantitative ◽  
Chemical Trait ◽  
The Subject ◽  
The Mean ◽  
Barley Genotypes ◽  
Collection Level

Work collections are subjected to a renewal process, therefore a regular evaluation is needed inorder to appreciate the genetic advance of the existing variability at collection level and further to identify valuable genotypes in terms of morphoproductive and qualitative traits (protein, starch). The barley intended for brewing must correspond to some qualitative parameters, of which proteins and starch content are of major importance. For this purpose, a study was conducted to assess the variability and heritability indicators corresponding to the two traits at 48 barley genotypes. The genotypes that were the subject of this study were sown in three experimental years 2013, 2014 and 2016. The mean values of 2013 year was 13.71 compared with only 10.77, and 11.27 in 2014 and 2016. The significant value of the heritability coefficient along with the genetic advantage of 0.81 indicates the success of selection work for this important chemical trait.

Paraquat selection identifies X-linked oxygen defense genes in Drosophila melanogaster

Genome ◽  
1993 ◽  
Vol 36 (1) ◽  
pp. 162-165 ◽  
Author(s):  
James M. Humphreys ◽  
Arthur J. Hilliker ◽  
John P. Phillips
Keyword(s):  
Drosophila Melanogaster ◽  
Xanthine Dehydrogenase ◽  
Oxygen Radical ◽  
Drosophila Genome ◽  
Induced Mutations ◽  
Defense Genes ◽  
Proximate Cause ◽  
Eye Color ◽  
Cuzn Superoxide Dismutase ◽  
New Alleles

We have previously shown that homozygous mutants of Drosophila melanogaster deficient in the oxygen radical scavengers, CuZn superoxide dismutase or urate, are adult viable and yet hypersensitive to the oxygen radical-generating agent, paraquat. Thus, paraquat could be used as a selective agent to identify adult-viable mutants potentially defective in other, perhaps unknown, oxygen defense functions. Here we report the successful use of paraquat hypersensitivity in the isolation of X-linked, ethylmethanesulfonate-induced mutations affecting oxygen defense in Drosophila melanogaster. Two paraquat hypersensitive mutants were identified that, by complementation analysis, were shown to be new alleles of the maroon-like gene. In addition to paraquat hypersensitivity, both alleles confer a maternally affected dark brown eye color and a complete lack of enzymatically active xanthine dehydrogenase, both of which are characteristic phenotypes of known maroon-like alleles. We conclude that the lack of xanthine dehydrogenase in these mutants leads to the absence of urate, which is the proximate cause of paraquat sensitivity. Because our search for such mutants on the X chromosome revealed two alleles of only a single selectable gene, we anticipate that the total number of major oxygen defense genes in the complete Drosophila genome may not be large.Key words: paraquat, maroon-like, xanthine dehydrogenase, oxygen defense.

scholarly journals SPONTANEOUS AND ETHYL METHANESULFONATE-INDUCED MUTATIONS CONTROLLING VIABILITY IN DROSOPHILA MELANOGASTER. II. HOMOZYGOUS EFFECT OF POLYGENIC MUTATIONS

Genetics ◽  
1977 ◽  
Vol 87 (3) ◽  
pp. 529-545 ◽  
Author(s):  
Ohmi Ohnishi
Keyword(s):  
Drosophila Melanogaster ◽  
Lower Limit ◽  
Mutation Rate ◽  
Large Fraction ◽  
Spontaneous Mutation ◽  
Induced Mutations ◽  
Spontaneous Mutation Rate ◽  
Lethal Rate ◽  
Successive Generations ◽  
Spontaneous Mutants

ABSTRACT Polygenic mutations affecting viability were accumulated on the second chromosome of Drosophila melanogaster by treating flies with EMS in successive generations. The treated chromosomes were later made homozygous and tested for their effects on viability by comparison of the frequency of such homozygotes with that of other genotypes in the same culture. The treated wild-type chromosomes were kept heterozygous in Pm/+ males by mating individual males in successive generations to Cy/Pm females. The number of generations of accumulation was 1 to 30 generations, depending on the concentration of EMS. A similar experiment for spontaneous polygenic mutations was also conducted by accumulating mutations for 40 generations. The lower limit of the spontaneous mutation rate of viability polygenes is estimated to be 0.06 per second chromosome per generation, which is about 12 times as high as the spontaneous recessive lethal mutation rate, 0.005. EMS-induced polygenic mutations increase linearly with the number of treated generations and with the concentration of EMS. The minimum mutation rate of viability polygenes is about 0.017 per 10-4 m, which is only slightly larger than the lethal rate of 0.013 per 10-4 m. The maximum estimate of the viability reduction of a single mutant is about 6 to 10 percent of the normal viability. The data are consistent with a constant average effect per mutant at all concentrations, but this is about three times as high as that for spontaneous mutants. It is obvious that one can obtain only a lower limit for the mutation rate, since some mutants may have effects so near to zero that they cannot be detected. The possibility of measuring something other than the lower limit is discussed. The ratio of the load due to detrimental mutants to that caused by lethals, the D/L ratio, is about 0.2 to 0.3 for EMS-induced mutants, as compared to about 0.5 for spontaneous mutants. This is to be expected if EMS treatment produces a large fraction of small deletions and other chromosome rearrangements which are more likely to be lethal.

scholarly journals SPONTANEOUS AND ETHYL METHANESULFONATE-INDUCED MUTATIONS CONTROLLING VIABILITY IN DROSOPHILA MELANOGASTER. III. HETEROZYGOUS EFFECT OF POLYGENIC MUTATIONS

Genetics ◽  
1977 ◽  
Vol 87 (3) ◽  
pp. 547-556 ◽  
Author(s):  
Ohmi Ohnishi
Keyword(s):  
Drosophila Melanogaster ◽  
Natural Selection ◽  
Large Fraction ◽  
Ethyl Methanesulfonate ◽  
Low Doses ◽  
Induced Mutations ◽  
Spontaneous Mutants ◽  
Discernible Difference ◽  
Repulsion Effect

ABSTRACT Spontaneous and EMS-induced mutations were accumulated for several generations on the second chromosome of Drosophila melanogaster by keeping this chromosome heterozygous under conditions of minimal natural selection. This article reports studies of heterozygous effects of these mutants.—Both lethal and mildly deleterious mutants have a deleterious heterozygous effect. There was no discernible difference between heterozygotes in which all the mutants were on one chromosome and those where the mutants were distributed over both homologs; thus the coupling-repulsion effect of Mukai and Yamazaki (1964, 1968) is not confirmed. The spontaneous polygenic mutants have a dominance of 0.4 to 0.5, and the same value is found at very low EMS doses. However, the value at higher EMS doses is only about half as high. Since the low doses have a large fraction of spontaneous mutants, the dominance of EMS mutants is less, in the range 0.1 to 0.3, but still larger than for lethals.

scholarly journals MODIFICATIONS OF MEAN OVARIOLE NUMBER, FRESH WEIGHT OF ADULT FEMALES AND DEVELOPMENTAL TIME IN DROSOPHILA MELANOGASTER INDUCED BY DROSOPHILA C VIRUS

Genetics ◽  
1984 ◽  
Vol 107 (4) ◽  
pp. 635-644
Author(s):  
Michele Thomas-Orillard
Keyword(s):  
Drosophila Melanogaster ◽  
Maternal Effects ◽  
Developmental Time ◽  
Fresh Weight ◽  
Adult Females ◽  
The Mean ◽  
Ovariole Number

ABSTRACT Drosophila C virus, a picornavirus that has some influence on ovarian morphogenesis, was discovered in a French strain of Drosophila melanogaster. When the strain was infected by Drosophila C virus (DCV), the mean number of ovarian tubes and weights of the adult females increased, but the developmental time from egg to imago decreased. The maternal effects observed when DCV was present disappeared when the strain was DCV free but were restored by experimental contamination.

scholarly journals VERMILION-DEFICIENCY

1919 ◽  
Vol 1 (6) ◽  
pp. 645-656 ◽  
Author(s):  
Calvin B. Bridges
Keyword(s):  
Drosophila Melanogaster ◽  
X Chromosome ◽  
The Other ◽  
Crossing Over ◽  
Actual Length ◽  
Eye Color ◽  
Lethal Action ◽  
Recessive Mutations ◽  
Slight Rise ◽  
The Individual

In May, 1916, a culture of Drosophila melanogaster showed that a new sex-linked lethal had arisen. The linkage relations indicated that the position of the lethal was in the neighborhood of the sex-linked recessive "vermilion," whose locus in the X chromosome is at 33.0. When females heterozygous for the lethal were outcrossed to vermilion males, all the daughters that received the lethal-bearing chromosome showed vermilion eye-color, though, from the pedigree, vermilion was known to be absent from the ancestry of the mother. The lethal action and the unexpected appearance of vermilion both suggested that this was another instance of the phenomenon called "deficiency;" that is, the loss or "inactivation" of the genes of a section of the X chromosome. The lethal action would then be due to the deficient region including one or more genes necessary for the life of the individual. The appearance of vermilion in females carrying only one vermilion gene would be explainable on the ground that the deficient-bearing females are virtually haploid for the region including the vermilion locus. Linkage tests showed that the amount of crossing over in the neighborhood of the deficiency was cut down by about five units. Part of this may be attributed to the actual length of the "deficient" region, within which it is probable that no crossing over occurs, and part (probably most) to an alteration in the synaptic relations in the regions immediately adjacent. In more remote regions there was no disturbance or perhaps a slight rise in the frequency of crossing over. Both the local fall and the possible rise in more distant regions would seem to argue that a "pucker" at synapsis had been caused by an actual shortening of the deficient chromosome. That the deficient region extends to the left of the locus of vermilion was indicated by a test in which it was observed that the presence of an extra piece of chromosome including the loci for vermilion and sable ("vermilion-sable duplication") did not neutralize the lethal action of the deficiency. Haploid tests with the other recessive mutations in the neighborhood of vermilion showed that the deficiency was not extensive enough to include their loci. Cytological preparations were made but were unsatisfactory. The stock was finally lost, apparently as the result of injurious action upon viability, fertility, and productivity by the deficiency.

scholarly journals A pleiotropic nonadditive model of variation in quantitative traits.

Genetics ◽  
1994 ◽  
Vol 138 (3) ◽  
pp. 883-900 ◽  
Author(s):  
A Caballero ◽  
P D Keightley
Keyword(s):  
Quantitative Traits ◽  
Spontaneous Mutation ◽  
P Element ◽  
Induced Mutations ◽  
Bristle Number ◽  
Degree Of Dominance ◽  
Population Sizes ◽  
Variable Gene ◽  
Segregating Population ◽  
New Mutations

Abstract A model of mutation-selection-drift balance incorporating pleiotropic and dominance effects of new mutations on quantitative traits and fitness is investigated and used to predict the amount and nature of genetic variation maintained in segregating populations. The model is based on recent information on the joint distribution of mutant effects on bristle traits and fitness in Drosophila melanogaster from experiments on the accumulation of spontaneous and P element-induced mutations. These experiments suggest a leptokurtic distribution of effects with an intermediate correlation between effects on the trait and fitness. Mutants of large effect tend to be partially recessive while those with smaller effect are on average additive, but apparently with very variable gene action. The model is parameterized with two different sets of information derived from P element insertion and spontaneous mutation data, though the latter are not fully known. They differ in the number of mutations per generation which is assumed to affect the trait. Predictions of the variance maintained for bristle number assuming parameters derived from effects of P element insertions, in which the proportion of mutations with an effect on the trait is small, fit reasonably well with experimental observations. The equilibrium genetic variance is nearly independent of the degree of dominance of new mutations. Heritabilities of between 0.4 and 0.6 are predicted with population sizes from 10(4) to 10(6), and most of the variance for the metric trait in segregating population is due to a small proportion of mutations (about 1% of the total number) with neutral or nearly neutral effects on fitness and intermediate effects on the trait (0.1-0.5 sigma P).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Mutations at the Darkener of apricot locus modulate transcript levels of copia and copia-induced mutations in Drosophila melanogaster.

Genetics ◽  
1993 ◽  
Vol 134 (4) ◽  
pp. 1175-1185 ◽  
Author(s):  
L Rabinow ◽  
S L Chiang ◽  
J A Birchler
Keyword(s):  
Drosophila Melanogaster ◽  
Induced Mutations ◽  
Long Terminal Repeats ◽  
Transcript Accumulation ◽  
Transcript Levels ◽  
Induced Mutation ◽  
Eye Color ◽  
Terminal Repeats ◽  
Copia Element

Abstract Mutations of the Doa locus of Drosophila melanogaster darken the eye color of the copia-induced white(apricot) (wa) allele and increase the accumulation of white promoter-initiated transcripts encoding functional mRNA. We show here that quantities of transcripts initiated in both long terminal repeats (LTRs) of the specific wa-copia element are increased, and those initiating in the 5' LTR of the element are structurally altered, yielding a slightly shortened transcript. Accumulation of host-initiated transcripts of a copia-induced mutation within the achaete-scute complex, Hairy-wing Ua (HwUa), are reduced by Doa mutations. Finally, we show that homozygosity for Doa mutations increases the accumulation of copia transcripts from the population of elements in the genome. These results suggest that Doa modulates the severity of copia-induced mutations while functioning as a dosage-sensitive modulator of copia transcription.

scholarly journals Variabilitatea caracterelor biomorfologice la mutantul calcaroides de orz de primăvară în generațiile M3-M7

2021 ◽  
Author(s):  
Tatiana Grigorov ◽  
Keyword(s):  
Plant Height ◽  
Analysis Of Variance ◽  
Gamma Rays ◽  
Quantitative Traits ◽  
Spike Length ◽  
Mutant Form ◽  
Mean Values ◽  
Condi Tions ◽  
Spike Number ◽  
The Mean

The variability of quantitative traits (plant height, spike length, apical internode length, number of spikelets and grains per spike, number of productive tillers per plant) in barley calcaroides mutant of cv. Sonor induced by gamma rays (250 Gy) has been studied. The analysis of variance showed that year condi-tions were mainly responsible (10.59 to 46.96%) for variation of studied traits, followed by the genotype (1.48 to 20.5%) and the interaction of these factors (1.94 to 8.64%), with only one exception for number of grains per spike. Variation of this trait depends mostly on genotype factors. The mean values of all studied traits of mutant form were lower than of Sonor variety. This morphological mutant has a scientific importance.

scholarly journals Identification of Trans-dominant Modifiers of Prat Expression in Drosophila melanogaster

Genetics ◽  
2003 ◽  
Vol 164 (4) ◽  
pp. 1419-1433
Author(s):  
Nicolas Malmanche ◽  
Denise V Clark
Keyword(s):  
Drosophila Melanogaster ◽  
De Novo ◽  
Essential Gene ◽  
Single Copy ◽  
Induced Mutations ◽  
Coding Region ◽  
Rt Pcr ◽  
Transcription Start ◽  
Eye Color ◽  
Transcription Start Sites

Abstract The first committed step in the purine de novo synthesis pathway is performed by amidophosphoribosyl-transferase (EC 2.4.2.14) or Prat. Drosophila melanogaster Prat is an essential gene with a promoter that lacks a TATA-box and initiator element and has multiple transcription start sites with a predominant start site. To study the regulation of Prat expression in the adult eye, we used the Prat:bw reporter gene, in which the Prat coding region was replaced with the brown (bw) coding region. The pale-orange eye color of a single copy of Prat:bw prompted us to use a multicopy array of Prat:bw that was derived using P transposase mutagenesis and produces a darker-orange eye color in a bwD; st genetic background. We used a 13-copy array of Prat:bw as a tool to recover dominant EMS-induced mutations that affect the expression of the transgene. After screening 21,000 F1s for deviation from the orange eye color, we isolated 23 dominant modifiers: 21 suppressors (1 Y-linked, 5 X-linked, 4 2-linked, and 11 3-linked) and 2 enhancers (1 2-linked and 1 3-linked). Quantification of their effect on endogenous Prat gene expression, using RT-PCR in young adult fly heads, identifies a subset of modifiers that are candidates for genes involved in regulating Prat expression.

Sign in / Sign up

Export Citation Format

Share Document