A population genetic study on genetic diversity and evolutionary characteristics of Dipterocarpacea in tropical rain forests

热带雨林龙脑香遗传多样性及进化特征的群体遗传研究

• 批准号: 09839020
• 负责人: TACHIDA Hidenori
• 金额: $ 2.24万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09839020/
• 关键词: tropical rain forests; genetic diversity; GapC gene; Dipterocarpaceae; nucleotide diversity; the neutrality test; the nearly neutral model; molecular population genetics; 地理的構造; 平均適応度

In order to clarify how genetic diversity relates to species diversity found in Asian Dipterocarpaceae trees that comprise important components of tropical rain forests, we estimated DNA variation between and within species in the family. First, we determined the relationships among genera within the family by sequencing chioroplast DNA.The Asian family members were shown to be divided into two groups and the genus Shorea was found to include a few other genera. Next we determined genetic diversity between and within four species in Shorea, S.leprosula, S.acuminata, S.curtisii and S.parvifolia by direct sequencing. Although we could not detect any variation in a chloroplast DNA region, the nucleotide diversity in the partial GapC (nuclear) gene was found to be between 0.00 12 and 0.0029 per site in the four species. The divergence between species was between 0.00781 and 0.01621 . The selfing rate was estimated to be between 0.39 and 0.67.To understand evolutionary implications of sequence data in relation to selection, we analyzed the nearly neutral mutation model theoretically. First, changes of population size were shown to increase the dispersion index, an index measuring variability of evolutionary rates, under this model. Next, the powers of detecting selection using several tests of the neutrality including Tajimas test and the MK test were investigated assuming a multisite nearly neutral model. The analysis showed the importance of discriminating replacement and silent variation for detecting this type of selection. We could not detect selection from our GapC data but this may be due to very little replacement variation in this gene. We need to survey more gene regions to clarify genetic diversity and its meaning for species diversity in this family

为了澄清遗传多样性与亚洲龙脑香科树木中发现的物种多样性，包括热带雨林的重要组成部分，我们估计的DNA变异之间和内部的家庭中的物种。首先，我们通过叶绿体DNA测序确定了该科内属间的亲缘关系，发现亚洲科的成员可分为两个类群，Shorea属还包括一些其他属。接下来，我们通过直接测序确定了Shorea，S.leprosula，S.acuminata，S.curtisii和S.parvifolia四个物种之间和内部的遗传多样性。虽然我们不能检测到叶绿体DNA区域的任何变化，在部分GapC（核）基因的核苷酸多样性被发现是在0.0012和0.0029每个站点之间的四个物种。种间差异在0.00781 ~ 0.01621之间。自交率估计在0.39 ~ 0.67之间。为了理解序列数据与选择的关系，我们从理论上分析了近中性突变模型。首先，在该模型下，种群规模的变化被证明会增加离散指数，这是一个衡量进化速率变异性的指数。接下来，假设多地点近中性模型，研究了使用几种中性测试（包括Tajimas测试和MK测试）检测选择的能力。分析表明，重要的歧视更换和沉默的变化检测这种类型的选择。我们不能从我们的GapC数据中检测到选择，但这可能是由于该基因中很少的替换变异。我们需要调查更多的基因区域来阐明该科的遗传多样性及其对物种多样性的意义

项目成果

H.Araki and H.Tachida: "Bottleneck effect on evolutionary rate in the nearly neutral mutation model." Genetics. 147. 907-914 (1997)

H.Araki 和 H.Tachida：“近中性突变模型中进化率的瓶颈效应。”

N.Inomata: "Molecular Evolution of the Amy multigenes in the Subgenus Sophophora of Drosophila" Mol.Biol.Evol.14. 942-950 (1997)

N.Inomata：“果蝇槐亚属 Amy 多基因的分子进化”Mol.Biol.Evol.14。

H.Tachida and T.Kuboyama: "Evolution of Multigene families by gene duplication : a haploid model." Genetics. 149. 2147-2158 (1998)

H.Tachida 和 T.Kuboyama：“通过基因复制进行多基因家族的进化：单倍体模型。”

Kamiya,K.: "Molecular phylogeny of dipterocarp species using nucleotide sequences of two non-coding regions in chloroplast DNA." Tropics. 7. 195-207 (1998)

Kamiya,K.：“利用叶绿体 DNA 中两个非编码区的核苷酸序列进行龙脑香属物种的分子系统发育。”

T.Kajita: "Molecular phylogeny of Dipterocarpaceae in Southeast Asia based on nucleotide sequences of matK,trnL intron and trnL-trnF intergenic spacer region in chloroplast DNA." Mol.Phyl.Evol.10. 202-209 (1998)

T. Kajita：“基于叶绿体 DNA 中 matK、trnL 内含子和 trnL-trnF 基因间隔区的核苷酸序列，研究东南亚龙脑香科的分子系统发育。”