RESEARCH ARTICLE Spliceosomal introns in th q n

MexicoSpliceosomal introns are evolutionary conserved features ubiquitously found in eukaryotic genomes that interrupt the coding sequences of genes. Introns are transcribed into pre-mRNA, which is then processed to produce mature mRNA. The spliceosome is a conserved and versatile ribonucleoprotein machinery that generates the mature mRNA by splicing the exons via precise excision of the introns at the donor and acceptor sites [1,2]. Alternative serves as a mechanism for regulating gene expression. Over 40 % of plant genes (Arabidopsis thaliana and Oryza sativa) and over 90 % of human genes are processed by alternative splicing to generate multiple and assorted mature mRNA molecules [3-6]. Recent studies have identified specific introns that are able to enhance gene expression. In some cases, these introns enhance mRNA accumulation 10-fold higher than normal levels. This effect, known as intron-mediated enhancement (IME), is likely to be a conserved mechanism throughout evolution, as it has been described in diverse * Correspondence