Furthermore, they provide a record of transcript diversity due to modifications of the primary pre-mRNA transcript, such as alternate promoter usage, alternative splicing, alternate polyadenylation, and RNA editing.
Conservation and efficient usage, alternative sources, distributed generation and alleviating transmission congestion deserve study.
In an effort to improve the efficiency of its usage, alternative spectrum allocation models are being proposed.
The transcriptional process is regulated at multiple levels with differential promoter usage, alternative splicing, intron retention, and alternative polyadenylation etc.
Thus, RNAP II accumulated immediately upstream of low-usage alternative polyA sites.
However, the RNAP II profile greatly fluctuated between high-usage alternative polyA sites and low-usage sites.
These differences may be biologically relevant, such as alternative promoter usage, alternative splicing, alternative translation initiation, genetic variants, RNA editing, or technical artifacts, such as sequencing errors.
Moreover, we observed that there was a little peak in the RNAP II profile upstream of high-usage alternative polyA sites, which was attributed to the contribution of proximal sites of the high-usage alternative polyA sites.
In low-usage alternative sites, proximal sites outnumber distal sites; almost triple the percentage of distal sites (Additional file 8).
This is needed, because genome-wide methods have shown that the majority of genes have multiple isoforms, driven by alternative promoter usage, alternative splicing, or alternative transcription termination.
