Identification of a novel class of (not-so) small RNAs

In the December 1st issue of G&D, Dr. Hailing Jin and colleagues (UC Riverside) report on their discovery of a new class of small RNAs in Arabidopsis. These newly-discovered, 30-40 nt long small RNAs have been dubbed “long short interfering RNAs (lsiRNAs),” and are induced by bacterial infection or under specific growth conditions. While liRNAs share some hallmark features with other, previously identified classes of plant small RNAs, there are also some important differences: In addition to their relatively large size, lsiRNAs have unique biogenesis and target degradation pathways. Dr. Jin adds that “Our study suggests that small RNA families and small RNA-mediated gene regulation are far more diverse and complex than we expected. These novel lsiRNAs may play important roles in host immunity.”