Fig. 2

Cis-elements and trans-acting factors regulate pre-mRNA splicing during myogenesis. a Pre-mRNA harboring various cis-acting regulatory sequences able to promote (+) or inhibit (−) recognition of alternative splicing exons. Based on their position, these elements are called intronic splice silencers (ISS) and enhancers (ISE); exonic splice silencers (ESS) and enhancers (ESE). b A depiction of the enrichment of consensus cis-elements bound by various trans-acting factors acting in a coordinated manner to regulate alternative splicing of multiple transcripts during myogenesis. The upstream or downstream binding of the trans-acting factors relative to the alternative exon dictates its inclusion or exclusion. Protein mentioned in the box are some of the trans-acting factors that regulate muscle-specific alternative splicing and are differentially expressed during the course of myogenesis