ExonIntronsspezifische

ExonIntronsspezifische is not a standard term in molecular biology, but it can be used to describe features and regulatory phenomena that are specific to exons or introns, as well as their interactions during pre-mRNA processing and splicing.

Exon-specific features include coding sequences, maintenance of reading frames, and exonic splicing enhancers (ESEs) that promote inclusion of the exon by recruiting serine/arginine-rich (SR) proteins. Exons often harbor conserved motifs and, in some genes, alternative exons encode protein domains. The integrity of exon boundaries is important for proper translation and for the generation of diverse protein isoforms.

Intron-specific features include regulatory elements such as intronic splicing enhancers (ISEs) and silencers (ISSs), the branch point, and the polypyrimidine tract that support spliceosome assembly. Introns also influence transcriptional regulation, mRNA export, and may affect gene expression through intron-mediated enhancement in some organisms. Introns contribute to evolutionary modularity by enabling exon shuffling and the creation of new isoforms.

Exon–intron junctions are defined by sequence motifs at the 5' splice site (donor) and the 3' splice site (acceptor), along with the branch point and polypyrimidine tract. Depending on transcript length and species, cells may use exon definition or intron definition strategies during splicing, which shapes exon inclusion patterns and mRNA diversity.

Relevance and research: Understanding exon- and intron-specific regulation illuminates mechanisms of alternative splicing, tissue-specific expression, and disease. Techniques such as RNA sequencing, crosslinking immunoprecipitation, and minigene assays are used to map regulatory elements and test their effects on exon inclusion.