基于DNA分子标记的花粉流动态分析

doi:10.3724/SP.J.1003.2014.13135

摘要/Abstract

摘要：

花粉介导的基因流是植物有性繁殖世代之间的桥梁, 花粉散布属性是植物繁殖生态学、保护生物学和进化生物学研究关注的焦点。随着DNA分子技术的发展, 花粉流分析所使用的分子标记(尤其是微卫星标记)逐步替代了早期物理标记, 基于最大似然法估计以及新兴的基于贝叶斯推断的父本指派算法的发展, 能有效地估计花粉流散布的方向、距离和强度等重要特征。花粉散布曲线由单一参数向多参数模型发展, 以更好地获得花粉散布特征的拟合效果, 双组分的复合模型利用相互独立的参数空间使得散布曲线在长距离和短距离形状上呈现更大的可塑性。这些革新的技术和方法被成功应用于植物性别表型、隔离种群和杂交物种间花粉流分析, 以探讨进化、生态和保护等多领域的基础理论问题。近年来, 高通量测序技术的发展将进一步加快以分子标记为基础的花粉流动态分析在更广泛的植物类群中运用。

关键词: 分子标记, 基因流, 花粉散布, 亲本分析, 父本指派, 散布曲线, 高通量测序

Abstract

Modes of pollen dispersal are important for plant ecology, conservation, and evolutionary biology as pollen-mediated gene flow connects one generation of sexually-reproducing plants to the next. With the development of DNA molecular techniques, molecular markers (especially microsatellite markers) have replaced traditional physical markers for pollen flow analysis. Methods of paternity assignment with maximum likelihood and Bayesian inference have greatly improved the estimation of pollen flow characteristics with regard to direction, distance, and strength. Pollen dispersal curves have been characterized by single parameter, two-parameter, multi-parameter, and two-component composite models to better evaluate the shape of dispersal distributions. These innovative techniques and methods have been successfully applied to assess pollination patterns in studies of plant sexual polymorphism, population connectivity, and natural hybridization, which, in turn, have provided important insights into basic theories of evolution, ecology, and conservation. In the coming years, high-throughput sequencing technologies are expected to accelerate the application of molecular marker-based pollen flow analysis across a wide range of plant taxa.

Key words: molecular marker, gene flow, pollen dispersal, parentage analysis, paternity assignment, dispersal kernel, next-generation sequencing

周伟, 王红 (2014) 基于DNA分子标记的花粉流动态分析. 生物多样性, 22, 97-108. DOI: 10.3724/SP.J.1003.2014.13135.

Wei Zhou,Hong Wang (2014) Pollen dispersal analysis using DNA markers. Biodiversity Science, 22, 97-108. DOI: 10.3724/SP.J.1003.2014.13135.

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链接本文: https://www.biodiversity-science.net/CN/10.3724/SP.J.1003.2014.13135

https://www.biodiversity-science.net/CN/Y2014/V22/I1/97

图/表 3

图1 花粉散布轨迹的正向物理跟踪标记和反向遗传回溯标记

Fig. 1 The forward physical and backward genetic marker for pollen dispersal analysis

图2 4种常用模型代表的花粉散布曲线及其尾部特征。单参数: 常态分布模型, 指数分布模型; 双参数: 指数幂分布模型, 韦伯分布模型。

Fig. 2 Example of curves and the characters of tail for the different pollen dispersal models. Single parameter: normal distribution model, exponential distribution model; Two parameters: exponential power distribution model and Weibull distribution model.

图3 3个层次的花粉流研究: 性别表型间花粉流, 隔离种群间花粉流和杂交物种间花粉流

Fig. 3 The pollen flow analysis at three levels: pollen flow between sexual morphs, between populations, and between hybrid species

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