Epigenetics includes DNA methylation and histones posttranslational modifications such as methylation, acetylation, phosphorylation among others. One of the most abundant modifications in histone tail is the methylation. It has been found that the methylation pattern in the histone H3 may provide understanding of the process involved in cell differentiation, adaptation, and evolution in plants. In this work, we detail a method for isolation of nuclear proteins from small amount of sample to identify global changes in different lysines of the histone H3 tail by using immunodetection.