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33. Mitochondrial DNA polymorphisms in the two subspecies of Drosophila sulfurigaster: relationship between geographic structure of population and nucleotide diversity.

Author

Tamura, K, Aotsuka, T, and Kitagawa, O

Abstract

Recent empirical and theoretical studies on mitochondrial DNA (mtDNA) variation in higher animals have suggested that the extent of mtDNA polymorphism is largely affected by spatial population subdivision. To examine this we studied mtDNA polymorphism in two subspecies of Drosophila sulfurigaster: D. s. albostrigata and D. s. bilimbata. Drosophila sulfurigaster albostrigata is mainly distributed on the mainland of Southeast Asia. In contrast, D. s. bilimbata forms discontinuous populations on many islands scattered in the Pacific Ocean. Because of the difference in their distribution patterns, the two subspecies are thought to be different in the extent of spatial population subdivision. mtDNA was isolated from greater than 50 isofemale strains for each subspecies and were analyzed by eight restriction endonucleases. Nucleotide diversity within a population was higher in D. s. albostrigata than in D. s. bilimbata. However, haplotype diversity was 1.6 times greater in D. s. bilimbata (0.85) than in D. s. albostrigata (0.53). The large difference in overall heterogeneity was attributed to the difference in interpopulational nucleotide diversity. For the two subspecies the proportion of interpopulational gene diversity in a subdivided population was calculated to be 0.54 in D. s. bilimbata and 0.40 in D. s. albostrigata. These observations indicate that spatial population subdivision is a major factor in determining mtDNA polymorphism in these subspecies. The extent of mtDNA divergence between the subspecies was very high. The average nucleotide divergence between them was 7.6%, which is almost the interspecific level reported for other Drosophila species. The cause of the high degree of mtDNA divergence is discussed.

Published
1991
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34. Catalytic Asymmetric Synthesis of Vicinal Diamine Derivatives through Enantioselective N-Allylation Using Chiral π-Allyl Pd-Catalyst

Author

Kitagawa, O., Yotsumoto, K., Kohriyama, M., Dobashi, Y., and Taguchi, T.

Abstract

N-Monoallylation of meso-vicinal diamine bistrisylamides using a chiral π-allyl-Pd catalyst proceeded in an enantioselective manner (up to 90% ee) to give desymmetrization products in good yields. The product was converted to the known σ-receptor agonist in short steps. In addition, the present catalytic asymmetric N-allylation was applied to kinetic resolution of racemic-diamide.

Published
2004

35. Radical Cascade Reaction with 1,4-Dienes and 1,4-Enynes Using 2-(Iodomethyl)cyclopropane-1,1-dicarboxylate as a Homoallyl Radical Precursor:  One-Step Synthesis of Bicyclo[3.3.0]octane Derivatives

Author

Kitagawa, O., Yamada, Y., Sugawara, A., and Taguchi, T.

Abstract

Radical cascade reaction with various 1,4-dienes and 1,4-enynes using dimethyl 2-(iodomethyl)cyclopropane-1,1-dicarboxylate as a homoallyl radical precursor smoothly proceeds through an iodine atom transfer mechanism to give functionalized bicyclo[3.3.0]octane derivatives in good yields.

Published
2002
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