2. The introns are cut out by processing enzymes in the nucleus and the exons(coding sequences)ligated together. 核内的加工酶切下内含子，同时外显子（编码序列）连接在一起。
3. Like eukaryotes, but unlike bacteria, they have introns in their transfer RNA, but like bacteria they have polycistronic operons (gene regulators). 像真核生物而不像细菌，转运RNA中含有内含子，还有细菌不具备的多顺反子的操纵子（基因的调控子）。
4. Objective To verify the self-splicing function of the group Ⅰ introns ribozymes from Tetrahymena thermophilic and the site-specific mutagenesis ribozymes. 目的验证嗜热四膜虫核酶自我剪接功能，定点诱变Ⅰ型内含子核酶及检测其自我剪接功能。
5. Objective To verify the self-splicing function of the group Ⅰ introns ribozymes from Tetrahymena thermophilic and the site-specific mutagenesis ribozymes. 目的验证嗜热四膜虫核酶自我剪接功能，定点诱变Ⅰ型内含子核酶及检测其自我剪接功能。
