Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 16/10 Miklukho-Maklaya, Moscow 117997, Russia.
Gene. 2012 Aug 15;505(1):128-36. doi: 10.1016/j.gene.2012.05.016. Epub 2012 May 15.
SVA elements represent the youngest family of hominid non-LTR retrotransposons. Recently, a human-specific subfamily (termed SVA(F1), CpG-SVA, or MAST2-SVA) was discovered representing fusion of the CpG island-containing exon 1 of the MAST2 gene and a 5'-truncated SVA. SVA(F1) includes at least 84 members, which suggests exceptionally high retrotransposition level. We investigated if the acquirement of the MAST2 CpG-island might play a role in the success of the SVA(F1) subfamily. We observed that in 16 samples representing seven human tissues, MAST2 was cotranscribed with the members of the SVA(F1) subfamily, but not with other retrotransposons. We found that the methylation status of the MAST2-derived sequences of SVA(F1) elements reversely correlates with the transcriptional activity of MAST2. The MAST2 sequence at the 5' end of SVA(F1) acts as a positive transcriptional regulator in human germ cells. Finally, in various testicular tissue samples we uncovered a transcriptional correlation of MAST2 with the human L1, Alu and SVA retrotransposons.
SVA 元件代表了朊病毒非 LTR 反转录转座子家族中最年轻的一个分支。最近，人们发现了一个人类特异性亚家族（称为 SVA(F1)、CpG-SVA 或 MAST2-SVA），它代表了 MAST2 基因含有 CpG 岛的外显子 1 和 5' 截短的 SVA 的融合。SVA(F1)至少包含 84 个成员，这表明其反转录转座水平异常高。我们研究了 MAST2 的 CpG 岛的获得是否可能在 SVA(F1)亚家族的成功中发挥作用。我们观察到，在代表七种人类组织的 16 个样本中，MAST2 与 SVA(F1)亚家族的成员共转录，但与其他反转录转座子不共转录。我们发现，SVA(F1)元件中 MAST2 衍生序列的甲基化状态与 MAST2 的转录活性呈负相关。SVA(F1)5'端的 MAST2 序列在人类生殖细胞中作为一个正向转录调控因子发挥作用。最后，在各种睾丸组织样本中，我们发现 MAST2 与人类 L1、Alu 和 SVA 反转录转座子之间存在转录相关性。
