An 'SOS' for Metabolic Stress
Upon viral invasion, the body launches its defenses in an effort to fight the infection. When a protein called PKR binds double-stranded RNA (dsRNA) made by viruses, the act signals that the fight is on. Several years ago, Gökhan Hotamisligil from Harvard University, a collaborator in this study, reported that mice fed an unhealthy, high-fat diet activated PKR even in the absence of viral infection. This result prompted Brenda Bass and her team at the University of Utah to search for molecules that activated PKR during metabolic stress.
Unexpectedly, they found that this function was performed by small nucleolar RNAs (snoRNAs) from our own bodies, known primarily for their role in modifying RNA. A key question for future studies is whether the interaction between PKR and snoRNAs can be modulated to control the chronic inflammation that occurs in metabolic stress disorders like obesity and diabetes.