MicroRNAs Are Key Genomic Regulators

A recently published paper has revealed that as much as 30% of the human genome may be regulated by microRNAs, RNA fragments of 18 to 25 nucleotides that bind to mRNA molecules and interfere with protein synthesis.

Investigators at the Massachusetts Institute of Technology (Boston, USA) capitalized on the most up-to-date genome-sequencing data to compare the human genome to that of the dog, chicken, mouse, and rat and correlate correspondence between microRNAs and protein-encoding genes in the different species.

They reported in the January 14, 2005, issue of Cell that the nucleotide sequence of regulatory microRNAs has been conserved for at least 310 million years. More...