SECIS元件
SECIS元件全称为硒半胱氨酸插入序列（SElenoCysteine Insertion Sequence），是生物mRNA中一个长约60nt的RNA元件，次级结构为一茎环[1] ，此元件会使核糖体转译时不将UGA当作终止密码子，而将其作为编码特殊氨基酸硒半胱氨酸的密码子，因此为编码硒蛋白的mRNA所需。三域生物皆有SECIS元件[2][3][4][5]，虽皆为茎环结构，但彼此序列差异很大（不过洛基古菌的SECIS元件序列和真核生物的较为接近）[6]，细菌的SECIS元件通常紧跟在UGA密码子之后，真核生物与古菌的SECIS元件则位于mRNA的3'非转译区，可使mRNA中多于一个UGA密码子编码硒半胱氨酸，另外已知甲烷球菌属的一种古菌具有位于5'非转译区的SECIS元件[7][8]。真核生物的SECIS元件通常有特殊的A：G碱基配对，可能对其功能相当重要[9]。SECIS元件结合蛋白2（SECIS-binding protein 2，简称SBP2）可与SECIS元件结合以促进UGA密码子编码硒半胱氨酸[10]，并可避免mRNA被无义介导的mRNA降解（NMD）途径降解移除[11]。
| SECIS元件 | |
|---|---|
| |
| 一个SECIS元件可能的次级结构，碱基标示为依循IUPAC规则 | |
| 识别符 | |
| 代号 | SECIS_1 |
| Alt.代号 | SECIS |
| Rfam | RF00031 |
| 其他数据 | |
| RNA类型 | 顺式作用元件 |
参考文献
- ^ Walczak R, Westhof E, Carbon P, Krol A. A novel RNA structural motif in the selenocysteine insertion element of eukaryotic selenoprotein mRNAs. RNA. April 1996, 2 (4): 367–379. PMC 1369379
. PMID 8634917.
- ^ Mix H, Lobanov AV, Gladyshev VN. SECIS elements in the coding regions of selenoprotein transcripts are functional in higher eukaryotes. Nucleic Acids Research. 2007, 35 (2): 414–423. PMC 1802603 . PMID 17169995. doi:10.1093/nar/gkl1060.
- ^ Cassago A, Rodrigues EM, Prieto EL, Gaston KW, Alfonzo JD, Iribar MP, Berry MJ, Cruz AK, Thiemann OH. Identification of Leishmania selenoproteins and SECIS element. Molecular and Biochemical Parasitology. October 2006, 149 (2): 128–134. PMID 16766053. doi:10.1016/j.molbiopara.2006.05.002.
- ^ Mourier T, Pain A, Barrell B, Griffiths-Jones S. A selenocysteine tRNA and SECIS element in Plasmodium falciparum. RNA. February 2005, 11 (2): 119–122. PMC 1370700 . PMID 15659354. doi:10.1261/rna.7185605.
- ^ Kryukov GV, Castellano S, Novoselov SV, Lobanov AV, Zehtab O, Guigó R, Gladyshev VN. Characterization of mammalian selenoproteomes. Science. May 2003, 300 (5624): 1439–1443 [2021-05-23]. PMID 12775843. doi:10.1126/science.1083516. （原始内容存档于2018-07-23）.
- ^ Mariotti, Marco; Lobanov, Alexei V.; Manta, Bruno; Santesmasses, Didac; Bofill, Andreu; Guigó, Roderic; Gabaldón, Toni; Gladyshev, Vadim N. Lokiarchaeota Marks the Transition between the Archaeal and Eukaryotic Selenocysteine Encoding Systems. Molecular Biology and Evolution. 2016, 33 (9): 2441–2453. ISSN 0737-4038. doi:10.1093/molbev/msw122.
- ^ Wilting R, Schorling S, Persson BC, Böck A. Selenoprotein synthesis in archaea: identification of an mRNA element of Methanococcus jannaschii probably directing selenocysteine insertion. Journal of Molecular Biology. March 1997, 266 (4): 637–641. PMID 9102456. doi:10.1006/jmbi.1996.0812.
- ^ Rother M, Resch A, Wilting R, Böck A. Selenoprotein synthesis in archaea. BioFactors. 2001, 14 (1–4): 75–83. PMID 11568443. doi:10.1002/biof.5520140111.
- ^ JULIA E. FLETCHER, PAUL R. COPELAND, DONNA M. DRISCOLL, ALAIN KROL. The selenocysteine incorporation machinery: Interactions between the SECIS RNA and the SECIS-binding protein SBP2 (PDF). RNA. 2001, 7: 1442-1453 [2021-05-23]. （原始内容存档 (PDF)于2021-05-23）.
- ^ Donovan J, Copeland PR. Selenocysteine insertion sequence binding protein 2L is implicated as a novel post-transcriptional regulator of selenoprotein expression.. PLoS One. 2012, 7 (4): e35581. PMC 3328465 . PMID 22530054. doi:10.1371/journal.pone.0035581.
- ^ Chellan B, Zhao L, Landeche M, Carmean CM, Dumitrescu AM, Sargis RM. Selenocysteine insertion sequence binding protein 2 (Sbp2) in the sex-specific regulation of selenoprotein gene expression in mouse pancreatic islets.. Sci Rep. 2020, 10 (1): 18568. PMC 7596060 . PMID 33122797. doi:10.1038/s41598-020-75595-4.
- ^ Lambert A, Lescure A, Gautheret D. A survey of metazoan selenocysteine insertion sequences. Biochimie. September 2002, 84 (9): 953–959. PMID 12458087. doi:10.1016/S0300-9084(02)01441-4.
