BIOLOGY

An Alternative Process of Post-Transcriptional Modification of mRNA

An Alternative Process of Post-Transcriptional Modification of mRNA

In bacteria, mRNA generally does not undergo modification following transcription while tRNA is processed in bacteria with cleavage, addition, and modification. In eukaryotes complex processing occurs of both tRNA and mRNA. Nearly all mRNA primary transcripts in eukaryotes are spliced. Introns are excised. Variations of mRNA are possible on the same theme to produce the members of protein families, a prominent example being variations of antibody molecules.

Splicing is mediated by several families of trans-acting factors that interact with specific RNA sequences (Moore et al. 1993: 123). ...