Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy.
PLoS One. 2018 Mar 28;13(3):e0194502. doi: 10.1371/journal.pone.0194502. eCollection 2018.
Repetitive DNA represents the major component of the genome in both plant and animal species. It includes transposable elements (TEs), which are dispersed throughout the genome, and satellite DNAs (satDNAs), which are tandemly organized in long arrays. The study of the structure and organization of repetitive DNA contributes to our understanding of genome architecture and the mechanisms leading to its evolution. Molluscs represent one of the largest groups of invertebrates and include organisms with a wide variety of morphologies and lifestyles. To increase our knowledge of bivalves at the genome level, we analysed the Antarctic scallop Adamussium colbecki. The screening of the genomic library evidenced the presence of two novel satDNA elements and the CvA transposon. The interspecific investigation performed in this study demonstrated that one of the two satDNAs isolated in A. colbecki is widespread in polar molluscan species, indicating a possible link between repetitive DNA and abiotic factors. Moreover, the transcriptional activity of CvA and its presence in long-diverged bivalves suggests a possible role for this ancient element in shaping the genome architecture of this clade.
重复 DNA 是植物和动物物种基因组的主要组成部分。它包括转座元件 (TEs)，这些元件分散在基因组中，以及卫星 DNA (satDNA)，它们以串联方式组织成长阵列。重复 DNA 的结构和组织研究有助于我们理解基因组结构和导致其进化的机制。软体动物是最大的无脊椎动物群体之一，包括具有各种形态和生活方式的生物。为了增加我们对双壳类动物在基因组水平上的了解，我们分析了南极扇贝 Adamussium colbecki。基因组文库的筛选表明存在两种新的 satDNA 元件和 CvA 转座子。本研究中的种间研究表明，在 A. colbecki 中分离出的两种 satDNA 之一广泛存在于极地软体动物物种中，这表明重复 DNA 与非生物因素之间可能存在联系。此外，CvA 的转录活性及其在长距离分化的双壳类动物中的存在表明，这个古老的元件可能在塑造这个进化枝的基因组结构方面发挥了作用。
