Filippenkov Ivan B, Sudarkina Olga Yu, Limborska Svetlana A, Dergunova Lyudmila V
Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia.
Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia.
Gene. 2018 May 15;654:14-22. doi: 10.1016/j.gene.2018.02.030. Epub 2018 Feb 14.
The SGMS1 gene encodes the enzyme sphingomyelin synthase 1 (SMS1), which is involved in the regulation of lipid metabolism, apoptosis, intracellular vesicular transport and other significant processes. The SGMS1 gene is located on chromosome 10 and has a size of 320 kb. Previously, we showed that dozens of alternative transcripts of the SGMS1 gene are present in various human tissues. In addition to mRNAs that provide synthesis of the SMS1 protein, this gene participates in the synthesis of non-coding transcripts, including circular RNAs (circRNAs), which include exons of the 5'-untranslated region (5'-UTR) and are highly represented in the brain. In this study, using the high-throughput technology RNA-CaptureSeq, many new SGMS1 transcripts were identified, including both intronic unspliced RNAs (premature RNAs) and RNAs formed via alternative splicing. Recursive exons (RS-exons) that can participate in the multi-step splicing of long introns of the gene were also identified. These exons participate in the formation of circRNAs. Thus, multi-step splicing may provide a variety of linear and circular RNAs of eukaryotic genes in tissues.
SGMS1基因编码鞘磷脂合成酶1（SMS1），该酶参与脂质代谢、细胞凋亡、细胞内囊泡运输及其他重要过程的调控。SGMS1基因位于10号染色体上，大小为320 kb。此前，我们发现SGMS1基因在多种人体组织中存在数十种可变转录本。除了能提供SMS1蛋白合成的mRNA外，该基因还参与非编码转录本的合成，包括环状RNA（circRNA），其包含5'非翻译区（5'-UTR）的外显子，且在大脑中高度富集。在本研究中，利用高通量技术RNA-CaptureSeq，鉴定出许多新的SGMS1转录本，包括内含子未剪接RNA（前体RNA）和通过可变剪接形成的RNA。还鉴定出了可参与该基因长内含子多步剪接的递归外显子（RS-外显子）。这些外显子参与circRNA的形成。因此，多步剪接可能在组织中提供真核基因的多种线性和环状RNA。
