Tiny Molecules (IMAGE) Salk Institute Caption This is a graft between two genotypes of Arabidopsis thaliana, shown in a confocal microscopy image. One genotype has plasma membranes marked in yellow, and the other marked in red. Salk Institute and Cambridge University researchers studied the movement of sRNAs across the graft junction, and the resulting epigenetic changes in the plants' genome. Credit Charles Melnyk/University of Cambridge Usage Restrictions with credit and related coverage License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.