In this week's Science, a team led by Broad Institute scientists reports data showing how the genome-editing technology CRISPR can be adapted to modify RNA. CRISPR takes advantage of bacterial proteins to cut the double strands of DNA at precise locations in the genome. In their study, the researchers demonstrate how these proteins can be used to cleave single-stranded RNA — but not double-stranded RNA — as well as snip messenger RNA in bacteria in vivo. The investigators expect that the discovery could lead to a range of programmable molecular tools for RNA manipulation. GenomeWeb has more on this study, here.
Also in Science, an international research team publishes a study comparing the genomes of ancient and modern-day wolves and dogs, pointing to the possibility that dogs were domesticated independently in two different geographic regions. They specifically analyzed 59 mitochondrial DNA sequences from ancient European dogs that lived between 14,000 years and 3,000 years ago, as well as an ancient Irish dog that lived about 4,800 years ago, and compared the data to the full genomic sequences of modern wolves and dogs from across Western Eurasia and East Asia. They found a deep split separating the two groups that occurred at the time or several thousand years after the first appearance of domestic dogs in Europe and East Asia, in addition to a discontinuity in haplotype frequencies in Europe. Taken together, the findings suggest that dogs may have been domesticated independently in Eastern and Western Eurasia from distinct wolf populations. GenomeWeb also covers this study, here.
Finally, a German-led group reports in Science on a new technique that enables the mapping of transient RNAs. Called transient transcriptome sequencing, or TT-seq, the method involves fragmenting RNA before adding genetic sequence markers, thereby reducing marking bias. When the method was applied to human leukemia cells, the team was able to identify more than 10,000 new non-coding RNAs, as well as four key transcription termination sites. And there's more on TT-seq, here.