Editing RNA splicing (section)

===tRNA splicing===
[[tRNA]] (also tRNA-like) splicing is another rare form of splicing that usually occurs in tRNA.  The splicing reaction involves a different biochemistry than the spliceosomal and self-splicing pathways.

In the [[yeast]] ''[[Saccharomyces cerevisiae]]'', a yeast tRNA splicing [[endonuclease]] heterotetramer, composed of [[TSEN54]], [[TSEN2]], [[TSEN34]], and [[TSEN15]], cleaves pre-tRNA at two sites in the acceptor loop to form a 5'-half tRNA, terminating at a 2',3'-cyclic phosphodiester group, and a 3'-half tRNA, terminating at a 5'-hydroxyl group, along with a discarded intron.<ref name=trotta1997>{{cite journal | vauthors = Trotta CR, Miao F, Arn EA, Stevens SW, Ho CK, Rauhut R, Abelson JN | title = The yeast tRNA splicing endonuclease: a tetrameric enzyme with two active site subunits homologous to the archaeal tRNA endonucleases | journal = Cell | volume = 89 | issue = 6 | pages = 849–858 | date = June 1997 | pmid = 9200603 | doi = 10.1016/S0092-8674(00)80270-6 | s2cid = 16055381 | doi-access = free }}</ref>  Yeast tRNA kinase then phosphorylates the 5'-hydroxyl group using [[adenosine triphosphate]].  Yeast tRNA cyclic phosphodiesterase cleaves the cyclic phosphodiester group to form a 2'-phosphorylated 3' end.  Yeast tRNA ligase adds an [[adenosine monophosphate]] group to the 5' end of the 3'-half and joins the two halves together.<ref name=westaway1988>{{cite journal | vauthors = Westaway SK, Phizicky EM, Abelson J | title = Structure and function of the yeast tRNA ligase gene | journal = The Journal of Biological Chemistry | volume = 263 | issue = 7 | pages = 3171–3176 | date = March 1988 | pmid = 3277966 | doi = 10.1016/S0021-9258(18)69050-7 | url = http://www.jbc.org/content/263/7/3171.abstract | access-date = 2014-12-17 | url-status = live | doi-access = free | archive-url = https://web.archive.org/web/20181118212051/http://www.jbc.org/content/263/7/3171.abstract | archive-date = 2018-11-18 }}</ref>  NAD-dependent 2'-phosphotransferase then removes the 2'-phosphate group.<ref name=paushkin2004>{{cite journal | vauthors = Paushkin SV, Patel M, Furia BS, Peltz SW, Trotta CR | title = Identification of a human endonuclease complex reveals a link between tRNA splicing and pre-mRNA 3' end formation | journal = Cell | volume = 117 | issue = 3 | pages = 311–321 | date = April 2004 | pmid = 15109492 | doi = 10.1016/S0092-8674(04)00342-3 | s2cid = 16049289 | doi-access = free }}</ref><ref name=soma2014>{{cite journal | vauthors = Soma A | title = Circularly permuted tRNA genes: their expression and implications for their physiological relevance and development | journal = Frontiers in Genetics | volume = 5 | pages = 63 | date = 1 April 2014 | pmid = 24744771 | pmc = 3978253 | doi = 10.3389/fgene.2014.00063 | doi-access = free }}</ref>