What happens during RNA processing in eukaryotic cells?

During RNA processing in eukaryotic cells, introns, which are non-coding regions of the precursor mRNA (pre-mRNA), are spliced out while exons, the coding regions, are joined together. This process is essential for creating a mature mRNA transcript that can be translated into a protein.

The removal of introns and joining of exons ensures that only the necessary coding sequences are present in the final mRNA, which allows for the correct translation of the genetic information into functional proteins. This maturation process also includes the addition of a 5' cap and a poly-A tail, which further stabilizes the mRNA and aids in its export from the nucleus to the cytoplasm for translation.

This key step in gene expression is crucial for the regulation of protein synthesis and ultimately affects how genes are expressed. The efficient removal of introns and the proper arrangement of exons is a vital mechanism that distinguishes eukaryotic gene expression from that of prokaryotes, where such processing does not occur.