Improving cGMP detection

Increased awareness of the importance of microRNAs goes hand in hand with an increased need to follow their expression. Their small size of 22 nucleotides makes tracking them a challenge that requires new approaches and technology. Neely and colleagues now developed a method for detection of microRNA expression using locked nucleic acid probes and a multicolor confocal laser system; they achieved unprecedented sensitivity and were able to distinguish between microRNA family members that differ only in one nucleotide. Plasterk and colleagues used locked nucleic acid probes to follow the expression patterns of microRNAs during the embryonic development in zebrafish and mouse. They optimize the protocol for in situ hybridization and show high specificity and abrogated staining when one mismatch was introduced in the probe. Together these techniques offer answers to the questions of how much of a specific microRNA is expressed in a cell and where in the developing embryo this expression takes place. Brief Communication p27, Article p41, News and Views p12