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Genetic Information
Eukaryotes
RNA Processing & Splicing
Post-transcriptional modifications converting pre-mRNA to mature mRNA.
Overview
Eukaryotic pre-mRNA undergoes three major processing steps: 5' capping (7-methylguanosine addition), 3' polyadenylation (poly-A tail addition), and splicing (intron removal by the spliceosome). Alternative splicing generates multiple mRNA variants from a single gene, dramatically expanding proteomic diversity. The spliceosome is a large ribonucleoprotein complex containing five snRNPs (U1, U2, U4, U5, U6).
Cellular Location
Nucleus
Clinical Significance
~95% of human multi-exon genes undergo alternative splicing; splicing mutations cause ~15% of genetic diseases; target of antisense oligonucleotides (nusinersen for SMA).