Trans-splicing

Trans-splicing is a special form of RNA processing in eukaryotes where exons from two different primary RNA transcripts are joined end to end and ligated.

In contrast "normal" (cis-)splicing processes a single molecule. That is, trans-splicing results in an RNA transcript that came from multiple RNA polymerases on the genome. This phenomenon can be exploited for molecular therapy to address mutated gene products.

Trans-splicing can be the mechanism behind certain oncogenic fusion transcripts.

Trans-splicing is used by certain microbial organisms, notably protozoa of the Kinetoplastae class to produce variable surface antigens and change from one life stage to another.