Vibranovski Maria Dulcetti, Sakabe Noboru Jo, de Souza Sandro José
Laboratory of Computational Biology, Ludwig Institute for Cancer Research, Sao Paulo Branch, Rua Prof. Antonio Prudente 109, CEP 01509-010, São Paulo, SP, Brazil.
FEBS Lett. 2006 Mar 6;580(6):1621-4. doi: 10.1016/j.febslet.2006.01.094. Epub 2006 Feb 10.
It was recently shown that there is a predominance of phase 1 introns near the cleavage site of signal peptides encoded by human genes. It was suggested that this biased distribution was due to intron insertion at AGmid R:G proto-splice sites. However, we found that there is no disproportional excess of AGmid R:G that would support insertion at proto-splice sites. In fact, all nGmid R:G sites are enriched in the vicinity of the cleavage site. Additional analyses support an alternative scenario in which exon-shuffling is largely responsible for such excess of phase 1 introns.
最近的研究表明，人类基因编码的信号肽切割位点附近存在大量1类内含子。有人认为这种偏向性分布是由于内含子插入到AGmid R:G原剪接位点所致。然而，我们发现并不存在支持插入原剪接位点的AGmid R:G的不成比例的过量。事实上，所有nGmid R:G位点在切割位点附近都有富集。进一步的分析支持了另一种情况，即外显子重排很大程度上导致了1类内含子的这种过量。
