Functional Analysis between Post-spliced Introns and mRNAs in Different Expressed Genes of Plant

The spliceosome eliminates noncoding sequences called introns from pre-mRNAs in order to create mature mRNAs. The improved Smith-Waterman local alignment approach is used to compare the optimal matching regions between introns and mRNA sequences in different expressed Genes of 3 plants. Compared to genes expressed at lower levels, highly expressed have stronger matching segments. The results indicated that introns exhibit different biological functions in both highly expressed genes and lowly expressed genes. The relative matching frequency distributions of the mRNA sequences was highly consistent, and the matching strength in the UTR was much higher than that in the coding region. We also observed that introns of highly expressed genes showed a higher matching strength in the UTR compared with the introns of the lowly expressed genes. With respect to the GC content, the relative matching frequency of genes with low GC segments in the UTR were much higher, whereas those of the genes with low GC segments in the CDS region were much lower. accordingly, we speculate that the convergence of introns and UTR sequences can be achieved via the interaction between them, and the convergence is more significant in highly expressed genes. The results imply the miRNAs properties and those of the optimal matched segments are compatible, and they are regarded as a functional RNA fragment. In addition, our research results suggest that there are significant differences in the potential matching relationship between post-spliced introns and mRNA with highly and lowly expressed genes, the matching strength is correlated with the ability of introns in plants to enhance gene expression.