The pattern of geographic variation in karyotypes and mitochondrial DNA in chromosomal hybrid zones of Nelima nigricoxa (Arachnida, Opiliones)

黑蜘蛛（Arachnida、Opiliones）染色体杂交区核型和线粒体 DNA 的地理变异模式

• 批准号: 08640888
• 负责人: TSURUSAKI Nobuo
• 金额: $ 1.41万
• 依托单位: Tottori University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08640888/
• 关键词: Chromosomes; Hybrid zone; Speciation; MtDNA; Nelima nigricoxa; Opiliones; Arachnida; 地理的変異; 核型分化

To reveal the nature and formation process of chromosomal hybbrid zones in Nelima nigricoxa, we analyzed karyotypes, allozymes, and mtDNA for various populations of the species and the closely related congeners. A total of seven karyotypes were recongnized in Nelima nigricoxa : 2n=20 (Kyushu, Shikoku, and Chugoku district westward of the Asahi River), 2n=18a (West of Mt.Daisen, Tottori Pref.and Kinki district), 2n=18b (north of Okayama city), 2n=16 (Chugoku mountains eastward from the Asahi River), 2n=22a (Izu-Hakone), 2n=22b (Miura Peninsula), 2n=22c (Mt.Kiyosumi, Chiba Pref.). Of these, each of the three adjoining karyotype pairs (2n=20/18a, 2n=18a/16, and2n=16/18a) forms a hybrid zone with a width less than 1-3 km. In a population (Shimimu-dani) in a hybrid zone between 2n=16 and 18a in Sekigane-cho, Tottori Prefecture, the ratio of individuals with 2n=17 chromosomes was significantly lower than the expected ratio from the Hardy-Weinberg theorem (<0.02). The relative fitness of indi … More viduals with 2n=17 was 0.4 when taking 2n=16 equals 1. The figure was much lower than the relative fitness of heterozygotes, 0.7 obtained in a population (Kawadoko) in a hybrid zone (2n=18/20) in Mt.Daisen. Difference in the size of chromosomes that pertain to the chromosome rearrangement may explain this result.We analyzed sequences of about 1 kilobase pairs of CO I gene coded by the mtDNA for several population of N.nigiricoxa and some populations of the closest relatives. The phylogeny obtained was : (nigricoxa Mt.Kiyosumi, Chiba, 2n=22, genufusca Sapporo, 2n=22) (genufusca Tokusen Falls, Yamaguchi, 2n=22 (nigricoxa Tokusen Falls, Yamaguchi, 2n=20 (nigricoxa Mt.Senjo, 2n=18 (nigricoxa Makiyaha Mt.Daisen 2n=20, nigricoxa 2n=20 Makihara Mt.Daisen)))) and the bootstrap probability for each branch was 100% without exception. It was confirmed that grographic differentiation can be detected also in mtDNA level among some morphologically non-differentiatied populations of Nelima nigricoxa in the Chogoku district. Less

为了揭示黑脉金线虫染色体杂交带的性质和形成过程，我们分析了该物种不同种群及其近缘同源物的核型、等位酶和mtDNA。Nlima nigricoxa共识别出7种核型：2n=20(朝日河以西的九州、四国和初国地区)，2n=18a(大仙山、鸟取县和近海地区以西)，2n=18b(冈山市以北)，2n=16(朝日河以东的楚国山脉)，2n=22a(伊豆-箱根)，2n=22b(三浦半岛)，2n=22c(千叶岛清水山)。其中，相邻的三对核型(2n=20/18a、2n=18a/16和2n=16/18a)形成一个宽度小于1-3千米的杂交带。在鸟取县关根町2n=16-18a杂交区的群体(Shimimu-Dani)中，具有2n=17条染色体的个体比率显著低于Hardy-Weinberg定理(&lt；0.02)的预期比率。INDI…的相对适合度当取2n=16=1时，2n=17的个体数为0.4。这一数字远低于杂合子的相对适合度，在戴森山杂交区(2n=18/20)的群体(Kawadoko)中为0.7。与染色体重排有关的染色体大小的差异可能解释了这一结果。我们分析了几个nigiricoxa种群和一些近缘种群的mtDNA编码的约1kb碱基的CO I基因序列。所获得的系统发育为：(千叶黑曲霉Mt.Kiyosumi Mt.Daisen 2n=22)(山口黑曲霉tokusen Falls，2n=22(Nigricoxa tokusen Falls，2n=20(Nigricoxa Mt.Senjo，2n=18(Nigricoxa Makiyaha Mt.Daisen 2n=20，Nigricoxa 2n=20 Makihara Mt.Daisen)。结果表明，在长谷地区一些形态未分化的黑线莲居群中，也可以检测到线粒体DNA水平上的形态分化。较少

项目成果

Shear, W.A.., Tanabe, T.And Tsurusaki, N.: "Japanese chordeumatid millipeds. IV.The new genus Japanoparvus (Diplopoda, Chordeumatida, Hoffmaneumatidae)" Myriapodologica. 4 (11). 89-99 (1997)

Shear, W.A., Tanabe, T. 和 Tsurusaki, N.：“日本脊索足类千足虫。IV.新属 Japanoparvus（Diplopoda、Chordeumatida、Hoffmaneumatidae）” Myriapodologica。

Tsurusaki,N.& Shimada,T.: "Seasonal and geographic variation of the number of B-chromosomes in Metagagrella tenuipes (Arachnida : Opiliones)" Zoological Science. 13 (Suppl.). 39-39 (1996)

鹤崎，N.

Shear,W.A., Tanabe,T.& Tsurusaki,N.: "Japanese chordeumatid millipeds.IV. The new genus Japanoparvus (Diplopoda,Chordeumatida,Hoffmaneumatidae)" Myriapodologica. 4(11). 89-99 (1997)

剪切，W.A.，田边，T.

Shear, W.A., Tanabe, T.& Tsurusaki, N.: "Japanese chordeumatid millipeds.IV.The new genus Japanoparvus (Diplopoda,Chordeumatida,Hoffmaneumatidae)" Myriapodologica. 4 (11). 89-99 (1997)

希尔，W.A.，田边，T.

Tsurusaki, N., Fujioka, M.& Aoki, N.: "Geographic differentiation of Karyotypes in the Nelima genufusca group (Arachnida,Opiliones)" Zoological Science. 14 (Suppl.) (in press). (1997)

鹤崎，N.，藤冈，M.