The schematic depicts three different models for how methyllysine readers can sense and
transduce histone methylation marks into biological outcomes.
(A) A specific reader recognizes one mark and links it to one specific outcome. In this
way, distinct readers link different marks to alternate functional outcomes.
(B) Five distinct readers all specifically recognize the same mark, for example
trimethylated histone H3 lysine 4 (H3K4me3), resulting in five alternate biological
outputs being linked to the one mark.
(C) One reader binds to multiple different marks (such as H3K9me3, H3K27me3, and
H4K20me3), linking the three different marks to a single biological output.