Xu M Q, Shub D A
Department of Biological Sciences, State University of New York, Albany 12222.
Gene. 1989 Oct 15;82(1):77-82. doi: 10.1016/0378-1119(89)90032-2.
The self-splicing sunY intron of bacteriophage T4 shares a common secondary structure with other group I introns. A long open reading frame within the intron is entirely 3' of the structural elements conserved in all group I introns. This catalytic core is the smallest yet described for a self-splicing intron. An internal deletion of 728 nucleotides (nt), leaving 196 nt at the 5' end and 109 nt at the 3' end, allows normal self-splicing. Transcripts terminating 196 nt 3' of the 5' splice site retain catalytic activity.
噬菌体T4的自我剪接sunY内含子与其他I类内含子具有共同的二级结构。该内含子内的一个长开放阅读框完全位于所有I类内含子中保守的结构元件的3'端。这个催化核心是迄今所描述的自我剪接内含子中最小的。728个核苷酸（nt）的内部缺失，在5'端留下196 nt，在3'端留下109 nt，允许正常的自我剪接。在5'剪接位点3'端196 nt处终止的转录本保留催化活性。
