Rhode Clint, Roodt-Wilding Rouvay
Department of Genetics, Stellenbosch University, Private Bag X1, Matieland 7602, Republic of South Africa.
Biol Bull. 2011 Oct;221(2):147-54. doi: 10.1086/BBLv221n2p147.
Recent studies have shown the non-random distribution of microsatellite motifs between genomic regions within a particular species. This study investigates such microsatellite distributions in the genome of the economically important abalone Haliotis midae, via a bioinformatic survey. In particular, the association of specific repeat motifs to coding regions and transposable elements is investigated. An understanding of microsatellite genomic distribution will facilitate more efficient use and development of this popular molecular marker. A bias toward di- and tetranucleotide repeats was found in the H. midae genome. CA microsatellite units were the most abundant repeat motif, but were notably underrepresented in genic regions where GAGT repeats predominate. Approximately 17.5% and 21% of the microsatellites showed gene and/or transposable element associations, respectively. This could explain the high genomic frequencies of particular motifs across the genome and may allude to a possible functional role. The data presented in this study are the first to demonstrate such non-random dispersal of microsatellites in abalone and support previous findings arguing in favor of non-random distribution of repeat motifs.
近期研究表明，微卫星基序在特定物种的基因组区域之间呈非随机分布。本研究通过生物信息学调查，对具有重要经济价值的南非鲍鱼（Haliotis midae）基因组中的此类微卫星分布进行了研究。具体而言，研究了特定重复基序与编码区和转座元件的关联。了解微卫星基因组分布将有助于更有效地利用和开发这种常用的分子标记。在南非鲍鱼基因组中发现了对二核苷酸和四核苷酸重复的偏向性。CA微卫星单元是最丰富的重复基序，但在以GAGT重复为主的基因区域中明显较少。分别约有17.5%和21%的微卫星显示出与基因和/或转座元件的关联。这可以解释特定基序在全基因组中的高频率出现，并可能暗示其具有某种功能作用。本研究提供的数据首次证明了微卫星在鲍鱼中的这种非随机分布，并支持了先前关于重复基序非随机分布的研究结果。
