Revival of trade Рexchange of goods Рheralded the end of the Dark Ages in Europe, bringing upon the intellectual awaking of the Renaissance. Likewise, global and local histone exchange is shaping cell-type specific functions in the nervous system, critical for neurological plasticity and cognition. Original artwork by Dr. Alexey Soshnev (Rockefeller University) based on illumination from the 15th century Trattato de Arithmetica, depicting two merchants engaged in (histone) barter transaction, with histone H3/H4 dimer and nucleosome structures depicted (PDB structures 2HUE and AOI1, respectively).