Woudt L P, van den Heuvel J J, van Raamsdonk-Duin M M, Mager W H, Planta R J
Nucleic Acids Res. 1985 Nov 11;13(21):7729-39. doi: 10.1093/nar/13.21.7729.
Processing of intron-containing nuclear messenger RNAs in yeast require an internal conserved sequence (ICS) element, UACUAAC. Similar elements (ugCUAGAC) have been identified in sequences interrupting nuclear genes of the related ascomycete Neurospora crassa. To examine the structural splicing requirements in yeast, we constructed hybrid genes containing the intron of the Neurospora histone H3 gene and cloned them into high copy number yeast vectors. Subsequently we analyzed the RNAs transcribed in yeast from the fusion genes by Northern analysis and primer extended sequencing. It turned out that the Neurospora intron, which contains the sequence element UGCUAAC, can be removed, though very inefficiently, provided that it is located near the 5'-end of the primary transcript. This proves that an A at the second position of the ICS is no absolute requirement for splicing in yeast. In addition, the results indicate that the yeast splicing machinery is intron-position dependent.
酵母中含内含子的核信使核糖核酸的加工需要一个内部保守序列（ICS）元件，即UACUAAC。在中断相关子囊菌粗糙脉孢菌核基因的序列中已鉴定出类似元件（ugCUAGAC）。为了研究酵母中的结构剪接要求，我们构建了包含粗糙脉孢菌组蛋白H3基因内含子的杂交基因，并将它们克隆到高拷贝数酵母载体中。随后，我们通过Northern分析和引物延伸测序分析了酵母中融合基因转录的核糖核酸。结果表明，含有序列元件UGCUAAC的粗糙脉孢菌内含子，只要位于初级转录本的5'端附近，就可以被去除，尽管效率很低。这证明ICS第二个位置的A对于酵母剪接不是绝对必需的。此外，结果表明酵母剪接机制依赖于内含子位置。
