"The genes of more complex organisms are comprised of segments
called exons and introns.
The introns lie between the exons.
The whole gene is copied to RNA and then edited to remove the introns (‘spliced’ with a phenomenally complex machine called a ‘spliceosome’) to produce the protein-coding mRNA—or so it was thought.
This study of brain tissue reinforces that different mRNAs can be produced in various ways.
--Most commonly the splicing skips the first exon, or skips another exon, or includes an intron or uses an alternative last exon from another gene (in that order of frequency).
--Overall, the researchers found that over half of the genes produced more than one mRNA. Some produced mRNA transcripts for more than ten different proteins.
All this adds up to amazing complexity in the regulation of the genes.
Q: How do the cells decide how to edit each RNA (which protein to produce, and how much)?
The mind boggles at the sophistication of the divine design that researchers
are uncovering day by day."
CMI
