• Korean journal of applied entomology
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• v.34 no.4
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• pp.308-313
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• 1995

Drosophila melanogaster, D. simulans, and D. sechellia are closely related species which belong to the D. melanogaster complex; the first two cosmopolita and the last one restricted to th Seychelles archipelago. The phenogenetical relationship between this complex and their hybrids were investigated by the comparison of sex-comb tooth number an genital arch of male. In interspecific hybrids of all crosses between three species four hybrid males were produced and completely sterile. Males of D. simulans (${O}_{9}$) have significantly less sex-comb teeth (mean 8.35) than either D. melanogaster (OR, mean 10.73) and D. sechellia (Ja, mean 10.60). From the analysis by the number of sex-comb tooth in interspecific hybrids we could not represent the direction of heredity nature. each species of D. melanogaster complex were characteristic in the shape of the genital arch, which readily allows these species to be distinguished. The common structure of the genital arch in the interspecific hybrids were mosaic-like structure between parental species.

• Journal of Life Science
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• v.9 no.1
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• pp.69-75
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• 1999

Four species belonging to the Drosophila melanogaster complex were examined genetically and morphologically to analyze interspecific relationships. Insemination rates ranged from 96% to 99% within species crosses, but interspecific crosses among the four species exhibited a great variations in the frequency of successful matings. D. melanogaster females mated relatively well with males of other species and D. sechellia males were more successful in mating with females of other species. In the crosses among D. simulans, D. mauritiana and D. sechellia, hybrid flies were fertile in females, but sterile in males regardless of reciprocal matings. The phenogenetically relationship between this complex and their hybrids were investigated by the comparison of sex comb tooth number and genital arch of male. They were controlled by polygenic factors on the chromosome of both parents. The effects of temperature on viability of hybrids between D. melanogaster females and D. simulans males were investigated for detection of genes concerning the speciation. The temperature sensitivity of the hybrid was mainly controlled by genes located on the X chromosome of D. simulans males.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.216-224
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• 1994

Sex combs which lack in females are characteristic of some members of the subgenus Sophophora When present, they can be van/ from a single blistle to very extensive structures, but the meianogaster subgroup of the subgenus Sophophora have only on the f~rst tarsal segments of the fore legs. D mauritiona among the melanogaster compler of the melar~ogaster subgroup have significantly more sex comb teeth (mean 12.75) than other specie& and the yakubo complex (range of the mean 6.84-758) have less than the melanogaster complex (range of the mean 835-12.75). In sex comb tooth number of interspecd~ch ybrids among the melonogoster complex, there appeared difference u;ith parental species Thus, analysis of male sex comb tooth in FI hybrid could not exhibit the direction of hereditan/ nature. On the other hand, D auraria (the montium subgroup), D suzuki (the suzuki subgroup) and D, lutecens (the takohashii subgroup) of the melanogaster species have two sex combs on the first and second tarsal segments, and the mean number were different according to the species.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.1-13
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• 1992

Physiological toxic and mutagenic effects of gramoxone in Drosophila melanogaster were invetigated. Gramoxone was highly toxic on the development, resulting in of lowering the viability and in prolongation of the developmental times. Adults treated with gramoxone during the developmental stages caused a lowering of the productivity and a little chinge in protein quantity. But the effect on the sex-linked lethal mutagenesis was found to be negative. The order of mortality causing ado리t stoa형e feeding to gramoxone in the D. melanogaster complex was like this ; D. mauritiana, D. sechellia, D. simulans and D. melanogasteu Two species of the D. yakuba complex were alike. Those results were more or less correlation with speciation of the D. melanogaster subgroup.

• The Korean Journal of Zoology
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• v.35 no.2
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• pp.211-218
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• 1992

한국산 노랑초파리 군에 속하는 8종의 유전적 유연관계를 밝히고자 생식적 격리 그리고 수용성 단백질을 전기영동법으로 분석하였다. 생리적 격리 실험에서 교배전격리 실험결과를 Watanane와 Kawanishi model에 근거하여 보면 D. aurario complex 3종 중 D. triauror물가 원시종이며 남 auraria는 팍생종으로 나타났다. 교배후 격리 실험에서 나. melonogaster와 D. simuions의 교배시, D. melonogoster를 수컷으로 하였을 때는 불임의 수컷만이, 또 D. melonogaster를 암컷으로 곯였을 때는 불임의 암컷만이 출현하였다. 그리고 남 ouraria complex 3종간의 교배에서는 수정 능력이 있는 수컷과 암컷이 출현하였는데, 이는 아직 남 auraria Complex가 semispecies단계에 있음을 나타내는 것이라 할 수 있다. SDS-PAGE로 분석한 노랑초파리 군 8종의 band pattern을 densitometer로 scanning한 결과 남 susu상가 가장 특이하였으며, TDE에 의한 유전적 거리(Aquadro and Avise's)는 남 auror지와 봉 triauror지사이가 0.155로 가장 낮았고, D. melonogaster와 고. mfa 사이가 0.422로 가장 높았다. 본 연구의 결과를 UPGMA법 뜨로 분석하면, 한국산 노랑초파리 군 8종은 4개의 아군으로 나뉘어지며 이들은 2개의 다른 큰무리로 구분되었는데, D. suzu가기 아군, D. lutescens의 아군, D. melanogoster와 봉 simulons의 아군이 속한 큰무리와, D. mfa,0. ouroria, D. biauroria 그리고 남 triourario가 속한 다른 큰무리로 나눌 수 있다.

• BMB Reports
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• v.51 no.1
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• pp.1-2
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• 2018

Positive selection on a new beneficial mutation generates a characteristic pattern of DNA sequence polymorphism when it reaches an intermediate allele frequency. On genome sequences of African Drosophila melanogaster, we detected such signatures of selection at 37 candidate loci and identified "sweeping haplotypes (SHs)" that are increasing or have increased rapidly in frequency due to hitchhiking. Based on geographic distribution of SH frequencies, we could infer whether selective sweeps occurred starting from de novo beneficial mutants under simple constant selective pressure. Single SHs were identified at more than half of loci. However, at many other loci, we observed multiple independent SHs, implying soft selective sweeps due to a high beneficial mutation rate or parallel evolution across space. Interestingly, SH frequencies were intermediate across multiple populations at about a quarter of the loci despite relatively low migration rates inferred between African populations. This invokes a certain form of frequency-dependent selection such as heterozygote advantage. At one locus, we observed a complex pattern of multiple independent that was compatible with recurrent frequency-dependent positive selection on new variants. In conclusion, genomic patterns of positive selection are very diverse, with equal contributions of hard and soft sweeps and a surprisingly large proportion of frequency-dependent selection in D. melanogaster populations.