This is kind of a follow-on the my earlier post about the intricacies of gene regulation. Those busy little RNAs have a role in editing nucleotide sequences during the transcription/translation steps of turning a gene sequence into proteins. It’s a way that a few genes can generate a lot of different outcomes. From Science Daily.
It turns out that human complexity and diversity
may spring from a surprisingly few number of genes, relatively speaking. RNA
editing, the process by which cells use their genetic code to manufacture
proteins, can greatly increase the number of gene products generated from a
single gene, says Stefan Maas, assistant professor of biological sciences.
One result of the international (Human Genome) project came as a bit of a
shock. Scientists discovered that the body has only 30,000 genes, far fewer
than the 50,000 to 140,000 they had expected to find.
Moreover, scientists learned that some less complex, less diverse organisms
had more, or proportionally more genes than human beings. The rice genome
contains 50,000 genes and the fly contains 14,000, to cite two examples.
RNA editing involves the process by which cells use their genetic code to
manufacture proteins. More specifically, says Maas, RNA editing “describes the
posttranscriptional alteration of gene sequences by mechanisms including the
deletion, insertion and modification of nucleotides.” Nucleotides are compounds
that form the basic constituents of DNA and RNA.
Often working in tandem with another RNA modification mechanism called
alternative splicing, RNA editing, says Maas, can “increase exponentially the
number of gene products generated from a single gene.”
This work was done in neurobiology, but they’re talking about a pretty fundamental biological process, and the researchers thing this process coule be involved in some brain tumors.